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Black Forest
06-07-2010, 09:27 AM
I am building a sheep shearing machine. Don't laugh it's true!

I need to be able to restrain the hind legs after the sheep is on its back on the table. Think of a Y that you push the leg into and something closes over the Y sort of like a handcuff. This needs to be a one handed operation, meaning I hold the leg and push it into the restraint and the "cuff" closes from the push of the leg. And it needs to be released one handed. I need to just reach up and push or pull something and the leg is released. I keep coming up with all sorts of elaborate contraptions. There must be a simple solution.

My wife always accuses me of making things to complicated so now I need simple.

brian Rupnow
06-07-2010, 09:45 AM
Sounds kinky to me, but---Can you have a "fixed" jaw with two half round cut-outs in it, half the diameter of the sheeps legs, and a pair of pivotting jaws with a half round cut out on each one, hinged on one side. The leg goes in, the jaws swings shut, and latches with a "snap latch". The action of the sheeps leg being forced into the fixed jaw is what swings the pivotting jaw into the "latched" position. That way you don't have to do anything except grab the legs and push then into the fixed jaws. To release, you pull up on the latch pins and the pivotting jaws swing open, releasing the sheep.

Black Forest
06-07-2010, 10:06 AM
It does sound a little kinky doesn't it. But I am sure our Scottish friends on this forum have already invented something!

Would your idean require releasing two latch pins per foot? Each foot needs to be released individually. I can not visualize your latch mechanism Brian.

Evan
06-07-2010, 10:12 AM
A board with a couple of small gumboots attached, upside down and just high enough above the table that you can slip a foot into each one. :D

Black Forest
06-07-2010, 10:24 AM
The two legs will be approximately 18 inches apart. The restraints will pivot so as to allow the sheep to be turned on each side for shearing.

There is something available in Australia but the firm that manufactures the machines is impossible to deal with. I wanted to buy one of their machines but they do not follow through with anything they have told me they would do. This is with me working really hard to spend around 40,000 € with them. I cannot imagine what support might be like! So I decided I will build one myself.

I have everything else figured out what I want. Only the leg restraints are needed.

brian Rupnow
06-07-2010, 10:25 AM
Like this---
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheepholder.jpg

MichaelP
06-07-2010, 10:32 AM
For this amount of money you can hire dedicated leg holders and yet have a few bucks left in case you want to substitute a sheep with a more traditional object once in a while. ;)

But you may consider the following options too:


http://www.quirumed.com/data/images/productos/tlarge/sillon_de_ginecologia_y_urologia_electrico_con_ban deja_24778_2546.jpg


http://www.antonline.com/images/781607098453.jpg

http://www.amazon.com/Safariland-Standard-Hinge-Handcuff-Nickel/dp/B001VSZDPM/ref=sr_1_16?ie=UTF8&s=hi&qid=1275919366&sr=8-16

Black Forest
06-07-2010, 10:36 AM
This is for shearing the sheep, not recreational purposes!

Black Forest
06-07-2010, 10:40 AM
That would work Brian. The latch then could be some spring loaded pin, lever actuated. Uhmmm....

Black Forest
06-07-2010, 10:42 AM
I bet MiahealP must be from Scottland!

MichaelP
06-07-2010, 11:11 AM
Those Germans're just unable to mix business with pleasure! :D

Black Forest
06-07-2010, 11:29 AM
MichealP, you are funny.

I live in Germany, but I am not German!

MichaelP
06-07-2010, 12:06 PM
BF,
What a coincidence! I live in the US, but I'm not Scottish. :D

Black_Moons
06-07-2010, 12:19 PM
Im voting for some padded frufru handcuffs with the easy release latch insted of requiring keys, avilable at sexshops and toy stores everywhere.
... .. Err.... Thats kinda really wrong that they are avilable at those two locations.

http://pix.auctiva.com/pix/10/00/06/FURRY_LEG_CUFFS.JPG

$13 on ebay, Can't beat that...

914Wilhelm
06-07-2010, 12:36 PM
3 biggest lies in Wyoming (or is that Germany):

1. I won this here belt buckle in a rodeo.
2. of course my pickup trucks paid for.
3. Your honor, I was just helping that sheep get over the fence.

lakeside53
06-07-2010, 01:04 PM
Check out some New Zealand sources, particularly the Agricultural Universities for non-commercial sources of design.

Down there I have a big extended family that shears for a very good living, and they would fall into their beer laughing if they thought something "new" to restrain needed to be invented.;)

Black Forest
06-07-2010, 01:28 PM
Lakeside, Your extended family in NZ probably would not laugh or fall into their soup. There are so many injuries to sheep shearers that the wool growers are spending millions of dollars to try to come up with an alternative to bending over to shear the sheep. The concept of having the sheep presented to the shearer at waist height upside down and hind legs restrained is a very welcome advancement in the profession. I am sure if you ask your relatives they will inform you of that. Back injuries to sheep shearers account for 40 percent of all work related injuries in all of Australia and NZ. The wool growers and government are throwing millions of research dollars at the problem.

Black Forest
06-07-2010, 01:30 PM
Anyone know why Scottish men wear a Kilt (skirt)?

Black Moons, my wife won't let me use her frufru handcuffs on the sheep!

Tinkerer
06-07-2010, 02:26 PM
Why not just use some 2" webbing with some velcro to hold the legs? The metal clamps seem a bit much and could add injury.

Could not a simple hobble and a catch work?

alanganes
06-07-2010, 02:51 PM
Like this---
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheepholder.jpg

Brian,
You must be busy with "real" work. I would have expected you to post solidworks models, dimensioned drawings, and a working scale replica (complete with a tiny aluminum sheep) by now...
;)

John Stevenson
06-07-2010, 02:58 PM
What's wrong with the time honoured way of dropping the back legs into your wellington boots ?

Mcgyver
06-07-2010, 03:01 PM
how many have you to do? where i grew there'd be a sheep shearer who came around in the spring and sheared them, he handled them gently and rarely cut them...sheep are timid creatures and scaring the crap out of them will affect production

if you have massive volumes, you could build a henry ford assembly line style...I dunno, at the point i thought i needed that it might be time for another line of work :)

http://www.shearexpress.com.au/Sheep-restrained-ready-to-m.jpg

unless you are completely immobilizing the animal be careful; partially restraining could lead to broken legs.

most importantly make sure the sheep has a safe word

Black Forest
06-07-2010, 03:11 PM
Brian,
You must be busy with "real" work. I would have expected you to post solidworks models, dimensioned drawings, and a working scale replica (complete with a tiny aluminum sheep) by now...
;)


It is simple why Brian posted that drawing. He used a file system that would load into my CAD program!

Black Forest
06-07-2010, 03:25 PM
Using any sort of leather hobble or webbing hobble with either velcro or a buckle is not practical. That would require two hands to fix a leg. That would take to much time. The sheep is either on its side or on its back with its hind feet fixed. There is actually less stress to the sheep than conventional shearing.

We also have people that will come and shear your sheep here in Germany. I have always shorn my own sheep and I have the back injuries to prove it!

There are less injuries to the sheep using the platform. One, because the sheep is better restrained. Two the shearer is more comfortable and not wrestling with the sheep.

The Artful Bodger
06-07-2010, 03:33 PM
Lakeside, Your extended family in NZ probably would not laugh or fall into their soup. There are so many injuries to sheep shearers that the wool growers are spending millions of dollars to try to come up with an alternative to bending over to shear the sheep. The concept of having the sheep presented to the shearer at waist height upside down and hind legs restrained is a very welcome advancement in the profession. I am sure if you ask your relatives they will inform you of that. Back injuries to sheep shearers account for 40 percent of all work related injuries in all of Australia and NZ. The wool growers and government are throwing millions of research dollars at the problem.

I can tick a couple of the boxes here, I live in NZ and I shore thousands of sheep when I was younger and never got an injury, instead I got fitter, stronger and richer. I do not know where you got your figures from but anyway that is not the subject here.

More to the point, are you sure the legs need to be restrained? I know from experience that out of hundreds and hundreds of sheep very few actually put up any kind of struggle by kicking wildly in the air. However if you touch
their feet they will surely kick.

John

Black Forest
06-07-2010, 03:50 PM
I get my figures directly from the AWI. Also from many friends in the sheep business down under. Many men do not sustain injuries in the shearing process. There is an ideal size man to shear sheep. And it depends if you are fit before you start shearing. And if the stars are aligned correctly.

Using a platform and restraints enables more "normal" men to do the job everyday all day.

Black Forest
06-07-2010, 03:53 PM
More to the point, are you sure the legs need to be restrained? I know from experience that out of hundreds and hundreds of sheep very few actually put up any kind of struggle by kicking wildly in the air. However if you touch
their feet they will surely kick.

John[/QUOTE]

the reason for the leg restraint is not to stop the sheep from kicking. It is to position the leg such that the wool can be removed more efficiently and to roll the sheep as it is shorn. The unit will use air pressure with cylinders and bladders to move the sheep as it is shorn. The hind legs act as a lever to roll the sheep.

tdkkart
06-07-2010, 04:11 PM
What's wrong with the time honoured way of dropping the back legs into your wellington boots ?


That's the way we do it around here. Uh, er, um, so I've heard anyway.............

lost_cause
06-07-2010, 05:12 PM
Anyone know why Scottish men wear a Kilt (skirt)

cause sheep can hear zippers. and yeah, about the wellingtons. i heard the scots just dropped the rear legs into the front of your boots and well... you can figure out the rest.

Liger Zero
06-07-2010, 05:16 PM
This of course will be servo driven with a PLC system and robotic load/unload... right?

RobbieKnobbie
06-07-2010, 05:26 PM
Cuffs and restraints? Sounds like you're taking the wrong approach: try sweet talking them and if that doesn't work... just get 'em sh!tfaced.

The Artful Bodger
06-07-2010, 05:29 PM
the reason for the leg restraint is not to stop the sheep from kicking. It is to position the leg such that the wool can be removed more efficiently and to roll the sheep as it is shorn. The unit will use air pressure with cylinders and bladders to move the sheep as it is shorn. The hind legs act as a lever to roll the sheep.

You seem to be on the right path as that pretty much describes how an experienced shearer handles the sheep. The shearer uses his legs and knees to gently rool the sheep as it is being shorn but he/she does not use the legs as a lever which IMHO would surely bring on a kicking frenzy. The only stage I see as difficult in your scheme, assuming you would be shearing the same sequence, is the last side when the shearer lifts the sheeps head.

Best wishes for you project as many good men have tried and failed over the years but someone has to be first and it may well be you.

John

Sean
06-07-2010, 05:30 PM
Since the table already air and bladders, why not a toric bladder like a pressure cuff, hoof actuated by switch or IR beam?

jack3140
06-07-2010, 05:57 PM
in days of old when men were bold and the sheep were nervous them were the days lol

The Artful Bodger
06-07-2010, 06:03 PM
Not wishing to detract from your plan but I am wondering if all that is required is two rollers, parallel, horizontal or maybe angled slightly up at one end, firmly padded, about 50cm in diameter and say 150cm long and no more than 10cm apart.

If a sheep was lying on her back between those rollers you could do the underside, rear end, inside legs, neck and head, roll her one way to do one side then roll back to do the other side then give her a good roll to get her off and on to her feet again. The rollers could be powered with maybe a couple of foot pedals to control.

Make the whole machine in a frame that can be tilted down to make it easy to get her on to it.

The disadvantage is that you will not get the wool off in a nice one piece fleece but I think that would be rather hard to do with any system other than the traditional fully manual technique.

Just a thought.

tdmidget
06-07-2010, 06:23 PM
I get my figures directly from the AWI. Also from many friends in the sheep business down under. Many men do not sustain injuries in the shearing process. There is an ideal size man to shear sheep. And it depends if you are fit before you start shearing. And if the stars are aligned correctly.

Using a platform and restraints enables more "normal" men to do the job everyday all day.
Not often do you see both sheep and "normal men" in the same post.

brian Rupnow
06-07-2010, 07:32 PM
Brian,
You must be busy with "real" work. I would have expected you to post solidworks models, dimensioned drawings, and a working scale replica (complete with a tiny aluminum sheep) by now...
;)
Alanganes---You just got a great laugh out of me!!! ---and yes, I am crazy busy right now with "real work". I have worked right thru the last two weekends trying to get a very "time sensitive" job finished for one customer, so that I can start another "time sensitive" job for a second customer.---Brian

Your Old Dog
06-07-2010, 07:39 PM
I don't know much about sheep and I probably shouldn't be trying to speak for them but I'm sure they'd much rather you design a good foolproof butt plug instead of stirrups :D

Guys sitting in a Scottish Pub and his buddy walks in. He says excitedly, "Hey Bill, Mick Jagger was just here and said he got some inspiration for a new song he might call "Hey Jude, Get Off of My Cloud". Just then the barkeeper walks over within hearing range and says, "I doubt that's what he heard, more'n likely it was Angus up the road yelling at the kid across the meadow, "Hey McCloud, get off'n my yew". :D

bob ward
06-07-2010, 07:54 PM
As others have said, an enormous amount of research has been done over the years in Australia and New Zealand on improving on traditional sheep shearing methods, but I don't know that much of it has been adopted.
Try trawling through CSIRO for a few ideas.

Arcane
06-08-2010, 12:23 AM
Hang your shears up! There's a *new and improved* (http://www.sciencemag.org/cgi/content/summary/281/5376/511c) way of separating the wool from the ewes! ;)

lakeside53
06-08-2010, 01:24 AM
Lakeside, Your extended family in NZ probably would not laugh or fall into their soup. There are so many injuries to sheep shearers that the wool growers are spending millions of dollars to try to come up with an alternative to bending over to shear the sheep. The concept of having the sheep presented to the shearer at waist height upside down and hind legs restrained is a very welcome advancement in the profession. I am sure if you ask your relatives they will inform you of that. Back injuries to sheep shearers account for 40 percent of all work related injuries in all of Australia and NZ. The wool growers and government are throwing millions of research dollars at the problem.


Well... they did laugh (kindly).. and said they've seen many attempts to make it "easier" that may have done just that, but it was slower.

These guys shear at the highest levels.. and make great money - paid "per fleece. It's all about "how fast", certainly not about "how easy on the back". Unless it speeds things up, it won't be considered as helpful. If being naked and lying under the sheep resulted in shearing 5% more per day, they would:eek:


Back injuries.. Well... there's more to it that the mechanics. Shearing is seasonal and/or in bursts, and sadly many injuries result from pushing the limits of endurance (12-15 hour days...). It's a finite resource, and every sheep ($) you don't shear goes to someone else. It's a tough job if you are into it big - and you must be in top shape. Not all shearers maintain fitness the rest of the year, and of course if it's a job related injury, the Govt pays... :rolleyes: Ok.. no hate mail - only a small percentage work the system.

40% of ALL work related injuries? Where did you get that statistic?

torker
06-08-2010, 01:30 AM
This one is way too easy...
Picture a circle...made of rod...cut in half...one half is stationary...
There are two pieces of small pipe...one welded to each "end" of the half circle.
The other half circle has two rods welded to the ends.
The rods point down and one acts as a swivel pin...it slips into the pipe on one side...gets a washer welded to it so it can't pop out of the pipe.
That rod is longer than the other.
The "loose"half circle will swivel now...and you lift it up...swing it into place...then drop it down so the other rod slips into the other pipe...instant lockola!
Dang...I coulda built it faster than tell you...
Russ

Black Forest
06-08-2010, 06:10 AM
Torker, Good idea but that will not be a one handed operation. I would need to hold the leg in the cuff and then swing the other closed.

Brian's idea is great. It amazed me how in a few minutes he came up with excactly what I needed. But I guess that is why he gets paid the big bucks for designing stuff! Simple and effective. I had almost the same idea but I had a problem with the alignment of the closing mechanism. Brian had the short piece connecting the push rod to close to the pivoting part. I didn't think of that and it stopped me from going forward. I had an air cylinder closing the "handcuff". That would work because I could use a foot operated valve to control the cylinder. As I use other foot operated valves to control the table and tipping mechanism another valve would be no problem.

Black Forest
06-08-2010, 06:18 AM
Lakeside, I will look for where I read that about the 40% work related injuries.

Of course there are men that can shear 300 sheep everyday and not injure themselves. Then there are the multitudes that hurt themselves shearing 100 a day.

This device is for my own use not for commercial development. To shear sheep is not my job. But I want to shear my own sheep. Not unlike many on this forum who build things they can buy for less money and trouble. Sometimes it is the journey not the destination that is important. I am not trying to build anything that suits anyone but me. Some will look at it as not practical or even idiotic but it is what I "want" to do, not need to do. I hope you all can understand that concept. Think of all the things you all do in your big and small machine shops that would be so much "easier" to send out. I think you get my point.

Black Forest
06-08-2010, 08:16 AM
I found a link to something similar to what I am building.

http://www.youtube.com/watch?gl=AU&hl=en-GB&v=bB9RuS4jG3c

oldtiffie
06-08-2010, 09:58 AM
Here is the OP:

I am building a sheep shearing machine. Don't laugh it's true!

I need to be able to restrain the hind legs after the sheep is on its back on the table. Think of a Y that you push the leg into and something closes over the Y sort of like a handcuff. This needs to be a one handed operation, meaning I hold the leg and push it into the restraint and the "cuff" closes from the push of the leg. And it needs to be released one handed. I need to just reach up and push or pull something and the leg is released. I keep coming up with all sorts of elaborate contraptions. There must be a simple solution.

My wife always accuses me of making things to complicated so now I need simple.

And an early response:

A board with a couple of small gumboots attached, upside down and just high enough above the table that you can slip a foot into each one. :D

Legend (or fact??) has it that some "sheep-shaggers" in some countries do exactly that except that there is no table and the "shearer/shepherd" is still wearing the gum-boots when the sheep's rear legs go into the gum boots (known as "Wellies" or "Wellington" boots in the UK). Others are at the front of the(ir??) sheep and hold it by the ears.

Suffice to say that "shearing" is not the prime objective at all.

http://en.wikipedia.org/wiki/North-west_Derby_(Ireland)

Now I am not necessarily endorsing it nor am I necessarily accusing any country of it - you can make up your own minds for yourselves. But does it help the OP?

http://www.google.com.au/#hl=en&source=hp&q=sheep+shagging&aq=7&aqi=g-s2g4g-s1g3&aql=&oq=sheep+sha&gs_rfai=&fp=24f291d940157105

Black Forest
06-08-2010, 11:43 AM
Did any of you all watch the video I posted the link to? Their leg restraints I think are very similar in concept to the ones Brian suggested.

The Artful Bodger
06-08-2010, 04:09 PM
Did any of you all watch the video I posted the link to? Their leg restraints I think are very similar in concept to the ones Brian suggested.

I have seen various sheep work cradles with leg restraints such ad Brian suggested. (I cant watch the video as I have only narrow gauge 'broadband' here.)

The Artful Bodger
06-08-2010, 04:18 PM
I put one on the jokes thread for your Oldtiffie!:D

oil mac
06-08-2010, 05:56 PM
The Artful Bodger , Says, Re the sheep, "If you touch their feet they will surely kick" I have been along with some women, and the same premise holds good as well:D
Regarding your problems on sheep shearing, I will ask my pal BaaaaaaaaaaaSil for guidance:eek:

oldtiffie
06-08-2010, 07:07 PM
I put one on the jokes thread for your Oldtiffie!:D

Thanks AB.

Just don't continue using lanolin as a hair-dressing and you will be OK. Bay Rum or Brycreem will get a response too! They might think your are Elvis - or another breed of sheep!!

I'll send you some of mine.

brian Rupnow
06-08-2010, 07:23 PM
BlackForest---I just watched the video---Very innovative stuff!!! I watched the part with the leg restraint about 10 times, and it is pretty well exactly what I had visualized. There doesn't seem to be any pneumatics used on the leg restraint, just a simple mechanical lever with a lock system. The lock engages automatically, like a slam-latch when the sheeps leg is forced in, and it is manually unlocked by the shearer. do you need any further help?---Brian

The Artful Bodger
06-08-2010, 07:25 PM
Thanks AB.

I'll send you some of mine.

"Now there was this lawyer from Sydney.... {continued on joke thread}:D

oldtiffie
06-08-2010, 07:31 PM
Thanks AB.

Don't even mention the capers with the poddy calf!!!

brian Rupnow
06-08-2010, 07:59 PM
I've been thinking about this---I am certain that the leg restraint technology is available to purchase. When you think about all of the large animal surgeries that are done world wide--- including the de-nutting of bulls, stallions and rams, I am sure that a veterinarian would probably have some idea of who would market this kind of thing. I know that there is a lot of "stuff" available because many of my customers come to me wanting a custom design done for things that are commercially available. Part of my service to customers is to do a "technology search" before I custom design machines for them, because it is virtually always cheaper to buy an existing device than to design and build it from scratch. I did a quick internet search for "self locking leg restraints" but didn't find anything. Talk to a large animal vet.

Black Forest
06-09-2010, 01:25 AM
Thank you Brian. I have been researching this shearing machine for two years!

The vets don't use a quick attach/release type of leg restraint for the work they do on sheep. As you can tell by some of the responses on this thread, it is a looked on with a skeptical eye as to any change in the shearing process. I understand the skepticism. Some of the solutions have been very impractical. But just as in machine tools time marches on. Just think about CNC and such and how the "old school" machinists view innovation! It is the same in my profession.

I just need to figure out the slam latch.

The Artful Bodger
06-09-2010, 03:45 AM
BF, I am not at all sceptical of your efforts in fact I commend them. I know you are doing this for yourself and I centainly see that a practical device would be a godsend for many small flock holders.

I would however like you to look closely at the need to secure the hind legs as it is my experience that sheep in the position to be shorn hardly ever kick and securing their feet, apart from inviting them to kick, may also be a cause of injury.

On the subject of making a restraint, I think modern scaffolding systems have a sort of clamp fitting that attaches one pipe to another and they might be worth looking at for inspiration.

John

The Artful Bodger
06-09-2010, 03:51 AM
I've been thinking about this---I am certain that the leg restraint technology is available to purchase. When you think about all of the large animal surgeries that are done world wide--- including the de-nutting of bulls, stallions and rams, I am sure that a veterinarian would probably have some idea of who would market this kind of thing. I know that there is a lot of "stuff" available because many of my customers come to me wanting a custom design done for things that are commercially available. Part of my service to customers is to do a "technology search" before I custom design machines for them, because it is virtually always cheaper to buy an existing device than to design and build it from scratch. I did a quick internet search for "self locking leg restraints" but didn't find anything. Talk to a large animal vet.


Brian, there are of course systems for restraining cattle and other large animals but they are often in the form of a 'crush', the animal walks between two gate-type deviced and one or the other moves to hold the animal securely, cattle would have their head restrained too. On those that are intended to give access to the animal's feet the entire ensemble often rolls so the legs stick out but I do not think the legs are usually restrained, obviously there must be exceptions.

Black Forest
06-09-2010, 04:17 AM
The Artful Boodger,

The leg restraints are necessary in order to facilitate the rolling over of the sheep while being shorn. The typical procedure of pushing on the stifle area with one hand while shearing the hind leg is not practical on the waist high shearing stand.

For the crutching(shearing the backside) one leg is restrained and one leg pulled forward by the shearer.

It is a shame you can not view the video I posted a link to. It would clear up a few points for you as to what I am trying to accomplish.

I am not worried at all that I will injure the sheep with my approach.

To set your mind at ease, I am not a hobbyist in regards to livestock. Horses, cattle and sheep have been a business my whole life. Now machining that is another story! As regards machining I am at the embryo stage!

The Artful Bodger
06-09-2010, 05:39 AM
BF, no problems and best wishes for your project. My advice re not restraining the legs is offered with the best intentions and is according to my experience.

John

Black Forest
06-09-2010, 07:40 AM
John, I do appreciate your experience and do not dismiss it.

I have spent the whole morning working on a prototype leg clamp. When I get something put together no matter how crude I will post a picture.

I have also thought along the lines of some sort of inflatable cuff. Activated the same as the one Brian drew. Push the leg in against the back of the cuff and two bladders inflate around the leg. Push a lever on top of the clamp to release the air fast. But simple is better. The fewer moving parts the better.

MuellerNick
06-09-2010, 09:14 AM
I think, Brian's suggestion comes quite close. But it can be simplfied.
As I am an experienced and seasoned sheep sheerer, I know all about sheep. NOT!
But I think this is true for all animals and humans:
They don't have much force to move the leg forward, but they do have a lot of force pushing it down and to the back.
So a clamping mechanism like Brian's where the Vee is springoaded in such a way that it either snaps into the closed position or the open position is enough. This means, it doesn't require the piston with the U-shaped thingy and the rod from the Vee to the piston. Only the Vee needs a expansion spring so it snaps in either of two directions.

Hope that was clear, don't have an picture-upload-account.


Nick

brian Rupnow
06-09-2010, 09:25 AM
Without getting into this much more deeply, here is a simplified design. The grey part is the "stirrup" that the leg gets shoved into. The red part is the swinging part that locks the leg in place. First picture on the left shows it open ready to recieve the sheeps leg. Center picture shows the swinging part moved into locking position by the movement of the sheeps leg entering and pressing the arm. The dark blue part at the top of the swinging device has a notch in it that aligns with a spring loaded arm (not shown). Normally the spring loaded arm rides on the outer diameter of the blue part, untill it is aligned with the notch when the sheeps leg is in it. Then it snaps into the slot under spring pressure and stays locked untill you manually release it. The red swinging part can be lightly spring loaded to open as soon as the latch is released. The third picture shows the two parts individually just to make things clearer.---and sorry----No little aluminum sheep!!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSYOFSHEEPCATCHER.jpg

pressurerelief
06-09-2010, 11:00 AM
Why not just use an inflatable sheep. I hear they do not kick.

Black Forest
06-09-2010, 11:25 AM
Brian, now you have messed me up! Your NapkinCad I could open the file. This drawing I don't know if I can open it in my NapkinCad program!


Nick,

You would be surprised at how much force a sheep has to bring the legs forward! It would have to be a very heavy spring if it was to hold the leg by itself. I would be worried about bruising their legs. Maybe not?

Black Forest
06-09-2010, 11:29 AM
Brian, I spent the whole day so far trying to build a prototype of the first design. Now you go and simplify it on me.........But I think your latest idea has a lot of merit to it. Back to the workshop.....Plan G or is it H?

Black Forest
06-09-2010, 03:34 PM
Here is my first attempt to get all the mechanics correct. Very crude but it gives me an idea were everything needs to be located. Note that I included the mandatory knurled nut!

http://i853.photobucket.com/albums/ab91/burnandreturn/leg_clamp1.jpg
http://i853.photobucket.com/albums/ab91/burnandreturn/leg_clamp2.jpg

brian Rupnow
06-09-2010, 03:39 PM
BlackForest---Thats great!!! Damn, I love it when a plan starts to come together!!!!----Brian

MuellerNick
06-09-2010, 03:51 PM
You would be surprised at how much force a sheep has to bring the legs forward!

If the free end of the L-shaped hook is pointing more inward, you can pull as much as you want, it won't flip open. To release the leg, you'll have to rotate the hook.


Nick

Black Forest
06-09-2010, 04:22 PM
Nick, When the L shaped part is closed the clamp will not open pushing against the L. I played with all the location points until it would self lock. As it is now I only need a vertical lever to pull to open the clamp and free the leg. My first thoughts were to put a spring on the slide to open it when the release is activated. But the way it is now I actually don't need lock. Tomorrow I will actually put this contraption on a sheep's leg and see if it actually works. Also I will build one like Brian second picture.

MuellerNick
06-09-2010, 04:29 PM
Nick, When the L shaped part is closed the clamp will not open pushing against the L.

That's what I say. But you can leave out the piston if you make the L-shaped thing reach at the same place where the piston is.

Reduce to the max!

Nick

alanganes
06-09-2010, 04:32 PM
The third picture shows the two parts individually just to make things clearer.---and sorry----No little aluminum sheep!!!!


Curse you Brian, I was really hoping for the those!!

-Al

laddy
06-09-2010, 04:43 PM
I have found this thread to be fascinating! My knowledge of the sheep world is nill. The videos have been great and the humor excellant. The problem solving ideas and machining and engineering to accomplish the end desire, Great! I remember flying into the Munich airport in the 1950's on a prop plane from New York and there was the shepard and his sheep grazing between the runways! No security, no problems, no lost bagage,..... what a wonderful world days gone bye.. Fred

Black Forest
06-09-2010, 04:47 PM
Well Laddy, If you fly into my place you will see me standing there with my sheep and my Border Collies tending to the management of the flock.

Black Forest
06-09-2010, 04:50 PM
Nick, I don't get what you are talking about. Write what you mean in German, Bitte.

MuellerNick
06-10-2010, 05:00 AM
Nick, I don't get what you are talking about.

Missed that request, so B.F. phoned me today. I think even I wouldn't understand my own description in any language. So I faxed him a sketch.


Nick

Black Forest
06-10-2010, 09:08 AM
So I have made the next generation of leg clamp. I tried the first generation this morning on a sheep's leg. The clamp worked but with a leg in it, you can't open the clamp again. The part that pushes in cannot slide back out with the leg in it. Duh!

BUT I built one along the lines of Brian's second picture! I used a different style latch mechanism but the basic concept worked really well.

http://i853.photobucket.com/albums/ab91/burnandreturn/2leg_clamp3.jpg

Black Forest
06-10-2010, 10:47 AM
So we tried the second generation with a sheep's leg. It worked really well.
The U that the leg goes in is a little too big but that is easily rectified.

The Artful Bodger, The sheep never even tried to kick!

I lined the U with some plastic tubing for a little cushioning.

http://i853.photobucket.com/albums/ab91/burnandreturn/3legclamp3.jpg
http://i853.photobucket.com/albums/ab91/burnandreturn/3legclamp2.jpg
http://i853.photobucket.com/albums/ab91/burnandreturn/3legclamp1.jpg

MuellerNick
06-10-2010, 11:28 AM
I think this is the best setup. The locking mechanism is easy to make and rock solid.


Nick

Black Forest
06-10-2010, 11:54 AM
I just need to refine the locking mechanism a little.

Nick do you know of an online supplier here in Germany for different kinds of springs? I think my gumi band was ok for a test today but I would like to use actual springs.

MuellerNick
06-10-2010, 04:08 PM
Oh my God, springs!
Gutekunst Federn comes to my mind. But they sell them in hundrets.
In Munic, there is (or maybe was) MFZ, "Münchner Federn Zentrale". But they drove me to wind my owns. :mad:

Maybe your local BAYWA is a source, I'd ask.


Nick

Tobias-B
06-10-2010, 10:17 PM
...NINE pages on German sheep bondage??!??!!! you guys need to get out more...

hee

t

The Artful Bodger
06-11-2010, 01:40 AM
So we tried the second generation with a sheep's leg. It worked really well.
The U that the leg goes in is a little too big but that is easily rectified.

The Artful Bodger, The sheep never even tried to kick!


Thats good then!:D

Black Forest
06-12-2010, 01:53 PM
All you machinists eat your heart out. Look at all these compound angles and adjustments I built today. After I shear my sheep I can mount my leg restraint frame on a surface grinder to sharpen my tools.

http://i853.photobucket.com/albums/ab91/burnandreturn/4legclamp1.jpg

brian Rupnow
06-12-2010, 02:35 PM
BlackForest---I must admit, I'm fascinated by this. I wish we lived about 2000 miles closer together so I could come over and help. Even after 45 years of designing nifty things, I still get a big kick out of a project like yours.---Brian

Black Forest
06-12-2010, 03:04 PM
Thank you Brian. It is all just tacked together right now. I have the rollers mounted on a couple of 4 X 4 that are Lag bolted down to a palette. I don't know how far apart the rollers need to be to support the sheep but somewhat immobilize it at the same time. I might need to have a couple of more rollers that hinge up and down. Tomorrow I will put a sheep on it and give it a test.

Once I have things in the right place I will build a steel frame and the tipping section. That will be relatively easy compared to the leg restraints and rollers.

brian Rupnow
06-12-2010, 04:02 PM
The rollers in the video appear to ba about 3" in diameter with 1" gaps betweem the rollers. I think the rollers appear to be made from Ultra high molecular weight plastic (uhmw) or delrin, probably with a 1 1/2" diameter steel center ----a bit easier on the sheep than a metal roller.

Black Forest
06-12-2010, 04:20 PM
The rollers in the video are just PVC pipe I think. They are maximum 2" diameter. My rollers are 6" diameter and when finished will be upholstered.

In the video they aren't actually rollers. I don't think they rotate. When I add the additional rollers that will make more of a U to cradle the sheep more when it is directly on it's back these will be of a smaller diameter and will not need to rotate.

But it makes no difference to the sheep as to comfort. After all, the sheep is laying on a thick sheepskin rug! The sheep never gets off it's fleece until unloaded from the rollers.

brian Rupnow
06-12-2010, 06:32 PM
Damn---I'm having too much fun with this!!! My man and the roller mechanism are to scale, but I don't really know how big a sheep is. I've seen lots of them in the fields, but my "sheep" are only approximations. What diameter is a sheeps body---how high is their back off the ground---how long are they from front of chest to their butt?
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSEMBLYOFROLLERS.jpg

brian Rupnow
06-12-2010, 06:40 PM
How far out am I???
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEP.jpg

RB211
06-12-2010, 06:54 PM
Can't you gas the sheep and clip them when they are out?

The Artful Bodger
06-12-2010, 07:18 PM
How far out am I???


I would say not far off, just a little too big even for a big breed. I suggest the level of the sheep's back would be about mid-thigh on the human figure.

Big(ish) sheep:-
http://farm4.static.flickr.com/3112/2893641122_f9b5966f60_m.jpg

brian Rupnow
06-12-2010, 07:45 PM
Artfull Bodger---Thank you. I have printed out the drawing, and I will make the assumption that the men are about 70" tall. This will let me establish a "scale factor" and allow me to correct the size of my sheep.----Brian

brian Rupnow
06-12-2010, 08:18 PM
Okay--Here we go---with correct sized sheep
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSYOFSHEEPSHEARINGSTAND.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEP-CORRECTED.jpg

brian Rupnow
06-12-2010, 09:08 PM
BlackForest--I just watched the video again, and it looks to me like the gap between the rollers is about 1/3 the diameter of the roller---thats what I based my 3" rollers and 1" gap on.. You are probably right about the rollers not actually rolling, which would make for much cheaper fabrication,but if they did roll the sheep would roll over a lot easier when the leg restraint mechanism swung under power.

Black Forest
06-13-2010, 01:54 AM
Can't you gas the sheep and clip them when they are out?

The problem is not the sheep struggling. The problem is manipulating the sheep into the correct position to shear. Also shearing a sheep requires in some instances to stretch the skin to flatten the wrinkles in the skin. Doing this while bent over is very hard on the human body.

The other problem are the numbers of sheep involved and the expense. Wool is not worth anything. Shearing is now just a maintenance expense not a profit center. The wool is not worth what it costs to have it sheared off, but the sheep must be sheared for the sheep's comfort and health. Unshorn sheep do not gain as much weight as shorn sheep.

The Artful Bodger
06-13-2010, 02:16 AM
Wool is still valuable and is worth a few thousand Euro per ton.

oldtiffie
06-13-2010, 02:22 AM
Any help?

http://www.google.com.au/#hl=en&source=hp&q=shaun+the+sheep&aq=1&aqi=g10&aql=&oq=shau&gs_rfai=&fp=97556ce57ce57d56

The Artful Bodger
06-13-2010, 03:00 AM
Also shearing a sheep requires in some instances to stretch the skin to flatten the wrinkles in the skin.

There is another problem too in that where the sheep has a fleece that hangs together all shearing is best done right close to the floor, the reason being that a heavy fleece partly shorn will hang down pulling on the skin and leading to the risk of leather thongs getting mixed with your wool, not to mention blood over everything.

Black Forest
06-13-2010, 03:16 AM
Wool is still valuable and is worth a few thousand Euro per ton.

I am not sure of my figures or yours!

There is a big price jump in what the sheep owner gets paid and what clean wool as a commodity sells for. Same as buying meat.

Black Forest
06-13-2010, 03:28 AM
But is is only a question of how high the floor is in comparison to the shearer!

On my "machine" the fleece is still supported and not hanging down pulling on the skin.

The Artful Bodger
06-13-2010, 06:01 AM
I am not sure of my figures or yours!

There is a big price jump in what the sheep owner gets paid and what clean wool as a commodity sells for. Same as buying meat.

I think the farm gate price for wool is about 1300 Euro per ton. I think that would be about 6 or 7 bales, incidently once upon a time we could buy a new car for with just one bale of wool, sigh, the good old days!:cool:

The Artful Bodger
06-13-2010, 06:06 AM
But is is only a question of how high the floor is in comparison to the shearer!

On my "machine" the fleece is still supported and not hanging down pulling on the skin.


Thats good, because it is one of the things that has caused a problem with other designs of aids for shearing.

Black Forest
06-14-2010, 02:12 AM
I tried my machine/contraption with a sheep. The rollers worked great. The leg clamps were clumsy. So I spent most of Sunday researching and tinkering.

I built a much better clamp. No pictures yet but I will post some later this morning.

The sheep was very happy with my machine. It had a cigarette right after I finished!

The Artful Bodger
06-14-2010, 03:02 AM
Dare I ask, did you try the sheep without the leg clamps and did she struggle at all?:)

Black Forest
06-14-2010, 07:36 AM
Dare I ask, did you try the sheep without the leg clamps and did she struggle at all?:)

Yes I did and they did struggle with their legs free. As soon as the legs were immobilized they just laid there.

New version. I think I am getting real close to having a workable leg restraint.

http://i853.photobucket.com/albums/ab91/burnandreturn/5legclamp1.jpg

Black Forest
06-14-2010, 02:13 PM
I changed the locking mechanism. I milled two slots in the side of the receiver and reversed the locking mechanism. The latch slides down and catches. This way I don't need a spring to open the leg restraint. When I want to release the leg I pull the handle and use it to slide the stirrup forward and swing open the L shaped part that closes behind the leg. Works perfect. I have to thank all of you for all the great help. When I am working on this project in my shop I feel as if there is a crowd of people there with me! Brian with his great drawings and suggestions. The Artful Bodger telling me to make sure it is sheep friendly. Those with family in the shearing business standing there with their arms crossed with a skeptical eye but nevertheless encouraging me. Beer's are on me gentlemen.

http://i853.photobucket.com/albums/ab91/burnandreturn/5legclamp2.jpg

brian Rupnow
06-14-2010, 02:55 PM
Fantastic!!!!

Black Forest
06-14-2010, 03:17 PM
Please excuse how rough and crude this prototype looks. I did all the welds with no helmet! I would just close my eyes, look away and pull the trigger. When I make the actual unit to be put in service I will do it up all tidy and put on my helmet.

I could build a big frac trailer or concrete pumping trailer for oil wells in my sleep. But this little leg restraint is a different ball game for me.

Guido
06-14-2010, 03:25 PM
Black Forest----------No one around this site knows what a frac unit, or a cementing unit is. Who did/do you work for? Pictures of your local configurations would be appreciated.

--M, ex-Halliburton

Alan in Vermont
06-14-2010, 03:28 PM
Dare I ask, did you try the sheep without the leg clamps and did she struggle at all?:)

I never thought high rubber boots came with, or required, clamps

Black Forest
06-14-2010, 03:35 PM
Ah, Haliburton. Maybe I will paint this sheep shearing unit Haliburtion Red!

Guido
06-14-2010, 03:52 PM
Halliburton red is actually CocaCola red. The gray color is Ford's birch gray. Earle P. bought out his old employer, Perkins Cementing, in about 1937 where the trucks were originally red in color but had many layers of hardened, gray cement dust on the roofs.

Gave substance to oilfield saying: 'Gray hair and red arrsed'. Also: circus wagons.

Are you raising sheep near the oilfields of Germany?

--G

Black Forest
06-14-2010, 04:06 PM
I have nothing to do with oil in Germany.

laddy
06-14-2010, 05:01 PM
I just saw a show on TV where they were shearing an alpaca. They too had it on a table about waist high with leg starps on all four legs and one person holding the head down for the shearing. No fancy hydraulics but it seemed like a small operation. Amazing the animal seemed pretty calm! Fred

The Artful Bodger
06-14-2010, 05:33 PM
Looks good BF!:)

I dont know why your sheep kick on your machine as they, mostly, sit really docile when being shorn in the butt-on-floor position.:rolleyes:

Have you got a clever scheme to get them up onto the machine?

John.

Black Forest
06-14-2010, 05:45 PM
I will have a tipping mechanism. the sheep go up a ramp and into a squeeze chute. It will tip the sheep upside down and the sheep will slide onto my rollers. The rollers will be just below waist height. The tipping mechanism will be powered by compressed air.

brian Rupnow
06-14-2010, 05:53 PM
Blackforest---You are doing an amazing job on this project. We know its a prototype, and no one is going to condemn your worksmanship at this stage of things. ArtfullBodger---It really would be a benefit to you if you could find some way to view this video.---Brian
http://www.youtube.com/watch?gl=AU&h...&v=bB9RuS4jG3c

The Artful Bodger
06-14-2010, 06:54 PM
ArtfullBodger---It really would be a benefit to you if you could find some way to view this video.---Brian


I am downloading it now Brian, it will take some time to arrive via my narrow gauge 'broadband'.

The Artful Bodger
06-14-2010, 07:12 PM
I watched it, it does seem to have got the sheep shorn without too much drama.

However, shearers are paid NZ$1.80 per sheep (about 90 Euro cents) and this machine is no quicker so the time for capital pay back may be longer than eternity.

If profit is not the motive then this is as good as any I have seen.

John

Black Forest
06-15-2010, 02:34 AM
John, It is great that you took the time to download the video. You have offered very constructive advice to me.

The machine that I am building will not be exactly as the one in the video.

As to the economic motivations, As you can see in the video a machine to help shear enables a not so physical adept shearer to be proficient. Also an older shearer to keep shearing.

I am 58 years old and actually quite fit, but it is still very taxing on me to shear my sheep.

Economic factors are not my motivation in building this machine. It is the satisfaction of figuring all the necessary parts and processes out and bringing it all together. Much of what I have done in my life's work you can not hold in your hand or see it stand before your eyes. This project is quite black and white. It will either work or not. It will either make it easier to shear or not. It will save time or not. It is quite objective in nature. Most things I work on are very subjective and though rewarding it is nice to hold it in your hand. Of course holding the bank check in my hand for my normal work is also rewarding but different.

As I said in the beginning I am not trying to help the shearing industry. I am trying to save my own back!

The Artful Bodger
06-15-2010, 03:28 AM
Black Forest, from what I have seen of your project so far I am confident it will make what is very hard work much easier and no doubt it will be a most satisfying project too.

My parents retired from the farm when my father was about 65, up till then he was still shearing all his own sheep but it was taking a few weeks each year! When he was younger he set up a partnership with his brother and they shore hundreds of thousands of sheep over 30+ years with a portable machine driven by a hit and miss engine. They both bought farms with their earning and each raised and educated a family. My father has been gone for some time but he died at 92 and his brother is still going strong.

I am 62 but when I was 16 I could shear 200 in a day, I doubt that is still the case!:)

John

Black Forest
06-15-2010, 07:44 AM
I can still shear over 200 a day for a few weeks at a time. But it takes me longer to get over the stress on my body each year.

Here in Germany if I would hire a contractor to come in it would cost me 3 to 5 Euro's per head. I only get .05 cents a kilo for the wool.

The Artful Bodger
06-15-2010, 04:27 PM
I can still shear over 200 a day for a few weeks at a time. But it takes me longer to get over the stress on my body each year. Yes, that is the killer for sure.




Here in Germany if I would hire a contractor to come in it would cost me 3 to 5 Euro's per head. I only get .05 cents a kilo for the wool. We used to be paid 7 pounds ten per hundred, but that was a long time ago!:)

laddy
06-20-2010, 10:28 AM
How is the machine coming along? Can't wait for an update. Fred

brian Rupnow
06-20-2010, 05:52 PM
Black Forest---Do you ever have days when you feel like this???----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/MANWITH10000SHEEP.jpg

Black Forest
06-21-2010, 01:39 AM
Black Forest---Do you ever have days when you feel like this???----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/MANWITH10000SHEEP.jpg

When I get my machine finished that is exactly how it will be around here. The sheep coming to me and saying, "do me, do me, do me, do me"

Arcane
06-21-2010, 02:10 AM
"do me, do me, do me, do me" indeed......
http://www.youtube.com/watch?v=oCRE9qOgbug

Black Forest
07-03-2010, 03:37 PM
I have about one more hour of work on my shearing platform. Tomorrow morning I will finish it and then run some sheep through. I hope to take pictures and a video. Wish my sheep luck!

MuellerNick
07-03-2010, 03:47 PM
I will finish it and then run some sheep through.

Didn't they already melt?


Nick

brian Rupnow
07-03-2010, 03:51 PM
Can't wait to see this. I'm excited!!! Damn, I am getting old.---Sheep excite me!!!

Black Forest
07-04-2010, 03:39 PM
I ran some sheep through the shearing platform today. I have just a couple of things to change before I actually attempt to shear on it. The leg clamps worked flawlessly.

I purposely picked a small group of really difficult sheep. It was a good test.

I need a brake on my rollers! One sheep pushed and rolled right off the machine.

IN the picture you can see the two hind feet held in the clamps. My instincts on the clamp angles and height was right on the money.

http://i853.photobucket.com/albums/ab91/burnandreturn/Still0704_00003.jpg

brian Rupnow
07-04-2010, 05:39 PM
Have you got a pneumatic "squeeze and tipper" like the video or did you manhandle the sheep into position?---Brian

The Artful Bodger
07-04-2010, 05:48 PM
Looks very impressive! So you just roll them off the ramp?


I need a brake on my rollers! One sheep pushed and rolled right off the machine.

Oh! That sounds nasty, I trust there was no injury to man, machine or sheep?


Are your sheep normally so clean underneath? What breed is that? Anything like a border leicester?
http://www.ansi.okstate.edu/breeds/sheep/borderleicester/images/borderleicester-web-2.jpg

The wool is not unlike a BL.

Black Forest
07-05-2010, 02:43 AM
No air powered tipping device, yet. But for sure I will implement it in the future.

No damage was done to man, machine or sheep in the making of this picture!

There is actually no man handling in the tipping process. The sheep walks into the box you see with the wooden flap. Then I just tip the nose away from me and pull on the hip and the sheep rolls out and over onto it's back onto the rollers.

Black Forest
07-08-2010, 02:25 PM
This is the crude prototype shearing machine. It still needs some work but I sheared sheep on it today and it does what it is supposed to do. The leg restraints you all helped me with functioned perfectly. I still need to automate the tipping over of the sheep. In its present incarnation it is a little tricky to turn the sheep and have it land correctly.

I wish I had a picture of me adding something to the machine today while a sheep was in the tipping crate. I was welding a bracket on the machine and when I looked up the young man helping me had taken his helmet and put it over the sheeps face! I was not welding at the sheeps head and did not think it would have been a problem but he told me he knew to close his eyes but he was not sure the sheep did!!!!!!
http://i853.photobucket.com/albums/ab91/burnandreturn/shearingmachine2.jpg

brian Rupnow
07-08-2010, 07:15 PM
I love it!!! About the sheep tipper---If you pivot it at the bottom you can rotate it with an air cylinder. If you wanted to pivot it manually, think about two six foot diameter hoops running in guide rollers---the true axis of the hoops would be in line with the long axis of the sheep, but there wouldn't actually be any center axle there. That way you could roatate it by hand. I can make you a sketch if you aren't clear on what I mean.---Brian

Black Forest
07-09-2010, 07:18 AM
I love it!!! About the sheep tipper---If you pivot it at the bottom you can rotate it with an air cylinder. If you wanted to pivot it manually, think about two six foot diameter hoops running in guide rollers---the true axis of the hoops would be in line with the long axis of the sheep, but there wouldn't actually be any center axle there. That way you could roatate it by hand. I can make you a sketch if you aren't clear on what I mean.---Brian

A sketch would be great. I picture a giant gyroscope looking thing cnc'd with the shears in one place and the sheep spinning and turning all around moving against the shears. Sounds interesting!

brian Rupnow
07-09-2010, 10:00 AM
Okay---You asked for it---Here is the "Sheep Rotator"-part-1"--More to come.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEPROTATOR-PART-1.jpg

brian Rupnow
07-09-2010, 10:10 AM
You'll need a few of these---
http://i307.photobucket.com/albums/nn294/BrianRupnow/ROLLER-GUIDEWHEEL.jpg

Black Forest
07-09-2010, 10:26 AM
I was thinking that is what you meant. The problem I see is the hoops are in the way when shearing. I could imagine putting the hoops on the other axis and rolling the sheep over head over tail. But that would not present the sheep to the cradle. One problem with sheep is they will follow another sheep over a cliff but they won't go someplace alone. That is why there is a decoy sheep in the front of the shearing machine. So the sheep to be shorn will walk into the tipping box. With my machine as it is we have to put a lot of pressure on the sheep to get it to go into the box.

brian Rupnow
07-09-2010, 10:47 AM
Okay--sheep walks in, you rotate the cage by hand, slide sheep out onto shearing table. The brown legs are made to what ever is a convenient height to match your shearing table.
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheeprotatorfullassembly.jpg

Black Forest
07-09-2010, 12:28 PM
the problem is, when the hoops are rotated the sheep is on the opposite side from me and the shearing table. It would be better if the box the sheep walks into was hanging from the top of the hoops. Then when I pulled on the hoops to roll the sheep over the sheep would be on my side of the hoops and the hoops would not be in my way. Does that make sense?

Black Forest
07-09-2010, 12:33 PM
Better yet would be as you have drawn it so the sheep don't have to go up much of a ramp. pull the hoops toward me until the sheep has rolled over to flat and then have the box the sheep is in on rollers and pull it to me. Open the squeeze and slide the sheep out. I am really starting to like this concept!

brian Rupnow
07-09-2010, 12:52 PM
Like this---
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheeptippershortlegs.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheeptippershortlegsrotated90degree.jpg

Black Forest
07-09-2010, 01:02 PM
yes the sheep is now rotated 90 degree's. But it is too far away from me and my cradle that the sheep is actually shorn on. So the box that the sheep is in must be on rollers and roll across to me. Sort of like a drawer. Roll the sheep away and then pull the whole box to me and tip the sheep onto the cradle.

brian Rupnow
07-09-2010, 01:07 PM
???????
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheeptippershortlegsandslidetable.jpg

Black Forest
07-09-2010, 01:19 PM
Not quite right! The sheep must be squeezed or it will not stay still. As soon as I would pull the sheep out of the box onto those rollers the sheep would try to stand up and then the feces would hit the rotary oscillator!

The box the sheep is in which is now rotated to 90 degree's would need to slide to the other side of the hoops and then I would unsqueeze the sheep and roll it into the cradle.

If the top of the box was attached to the hoops then as I rolled the hoops the sheep would be in the correct place to unsqueeze and tip into the cradle. But the box on the bottom solves a big problem to get the sheep into the squeeze box in the first place. Sheep don't like to go up a ramp. so If I can keep the angle of the ramp very slight it would solve a lot of problems.

Black Forest
07-09-2010, 01:27 PM
The beauty of this design is that the sheep can be easily trained to go through the tipping mechanism. Just run the sheep through the box and out again until they just keep moving. Then just as the sheep enter the box squeeze them and hold them there until ready to tip.

brian Rupnow
07-09-2010, 01:32 PM
OKAY---
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEPTIPPERWITHSLIDETRAY-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/sheeptipper-slidetray-2.jpg

brian Rupnow
07-09-2010, 01:38 PM
It certainly gives food for thought doesn't it. Its amazing how a few models of an idea immediately spur new lines of thought and new/improved ideas. Although its all well and good if you have an air compressor and the appropriate controls, its always great to look at it from a purely "manual/mechanical" point of view. I don't doubt for a second that the "squeeze" portion of the design could be worked out using Thomson linear bearings and a Destaco like "cam-over" clamp.---Brian

Black Forest
07-09-2010, 01:40 PM
Nope....the whole box must slide across. The sheep will not stay on its side once out of the box. If they were sedated it would work the way you have it.

Just imagine two pipes going across the hoops. the box is not fixed to the hoops. On the box are some of the green rollers just like the hoops ride on. Then when the hoops are rolled and the box is at 90 degrees the whole box can be rolled in my direction to the opposite side of the hoops.

brian Rupnow
07-09-2010, 02:47 PM
Okay--Here we go--sheep walks into squeeze box almost at ground level--no ramp, or at least very little ramp required.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEPTIPPER-LOADPOSITION.jpg

brian Rupnow
07-09-2010, 02:49 PM
Stage #2 sheep is squeezed in box and box rotates 90 degrees with round hoops in guide rollers.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEPTIPPERROTATED90DEGREES.jpg

brian Rupnow
07-09-2010, 02:51 PM
Stage #3 box and sheep are slid across the hoops on a second set of guide rollers to position sheep correctly in relation to shearing table--"Squeeze" is released, and sheep pulled out onto shearing table. When hoops are rolled back to load position, gravity pulls "squeeze box" back into load position.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEPTIPPERROTATED90ANDBOXLIDACROSS.jpg

Black Forest
07-09-2010, 03:17 PM
That is exactly what I was talking about! How am I going to sleep tonight. I need to build this thing.

brian Rupnow
07-09-2010, 04:48 PM
The only thing difficult to fabricate are the two pipe "hoops". Most large fabrication shops can roll pipe to whatever diameter you require. The pipe I used for creating the models is 2 1/2" outer diameter and I wouldn't recomend anything less. In my model, the hoops are 72" in diameter at the centerline of the pipe---or, 74.5" O.D. The rectangular tubing end frames are 4" square, and the roller wheels are as the picture shows.
http://i307.photobucket.com/albums/nn294/BrianRupnow/ROLLER-GUIDEWHEEL-DRAWING.jpg

Black Forest
07-10-2010, 03:11 AM
Thank you Brian. With construction so heavy I could use it to shear Elephants also if the need arises!!!!

I think the whole thing will roll easier if I use the large size pipe, correct?

Rolling the pipe is no problem for me. Fabrication is not new to me, machining is new to me!

brian Rupnow
07-10-2010, 09:42 AM
That is relatively lightweight material for what you are doing. The wall thickness on both the tube and the pipe wouldn't have to exceed 3/16". Material is cheap--far cheaper than saving a dollar building everything undersized and THEN having to redo it all because its too flimsy.

Black Forest
07-11-2010, 02:55 PM
A friend of mine brought over some sheep for me to shear this morning. He didn't know I had built this machine. He was very skeptical until he saw me shear the first sheep. Then he wanted to shear his own sheep. I let him have a go at one and he quickly realized using the handpiece takes some practice. After about 20 seconds he handed the job back to me! He felt he had to help so I let him hold the front feet. It was not necessary but made him feel useful!

http://i853.photobucket.com/albums/ab91/burnandreturn/shearingSunday.jpg

brian Rupnow
07-12-2010, 01:48 PM
Here ya go---off the shelf, right size and everything---Looks like it even includes a bushing. I just took my pickup truck up to the garage for an oil change/tune-up and noticed the gate to their compound had the exact roller you require. A few minutes doing a web search yielded a supplier, web link, and picture. These have to be about a hundred times cheaper than having someone machine them.---Brian
http://www.hooverfence.com/cantilever/roller.htm
http://i307.photobucket.com/albums/nn294/BrianRupnow/cantroll.jpg

Black Forest
07-12-2010, 03:17 PM
Thanks Brian for the tip. I will probably turn the rollers because I want to put bearings in them.

My biggest problem is I don't have any more sheep with wool still on.

Tomorrow I go in for surgery on my left knee so I won't be very mobile for a couple of weeks. When the knee specialist looked at my X-rays and MRI he was shocked I walked in on my own. He told me if one of his soccer players had a knee like mine they would whine and be in a wheel chair. I guess I have a high tolerance for pain. Of course I do, I have a blond wife!

So my projects are on hold for a week or so. Sucks big time. Next project is a firewood processor. I already built a saw for my excavator.
http://www.youtube.com/watch?v=1PFG6jLU5cY

The Artful Bodger
07-12-2010, 04:28 PM
Best wishes for the surgery and you can be sure those sheep are already busy growing more wool!

laddy
07-12-2010, 06:24 PM
Sorry to hear about the knee. That sucks. Are they doing a repair or replacement? Hope all goes well. That is really Baaaaaaaaaaaaad! Best wishes Fred

Black Forest
08-18-2010, 11:04 AM
The leg restraints worked perfect. Now I need to automate the tipping of the leg restraints. I need to be able to pivot them 180 degrees and stop them anywhere in between. My thoughts are to use an air cylinder. It needs to be foot controlled so my hands are free. I wanted to just attach an air cylinder just below the pivot point and when the cylinder was extended half way the leg restraints would be standing straight up. If I extend the cylinder it would roll the leg restraints all the way over to one side. If I would retract the cylinder all the way the restraints would pivot 180 degrees the other way. The logistics of how to attach the cylinder is proving challenging!

brian Rupnow
08-18-2010, 12:19 PM
The leg restraints worked perfect. Now I need to automate the tipping of the leg restraints. I need to be able to pivot them 180 degrees and stop them anywhere in between. My thoughts are to use an air cylinder. It needs to be foot controlled so my hands are free. I wanted to just attach an air cylinder just below the pivot point and when the cylinder was extended half way the leg restraints would be standing straight up. If I extend the cylinder it would roll the leg restraints all the way over to one side. If I would retract the cylinder all the way the restraints would pivot 180 degrees the other way. The logistics of how to attach the cylinder is proving challenging!

The easiest way to do that consistently is to use two shorter cylinders bolted back to back with one rod eye fixed to a stationary point and the other cylinder eye attached to your tipper mechanism. When one cylinder is extended and one is retracted, the legs are held straight up. When both cylinders are extended, the legs are swung 90 degrees in one direction. When both cylinders are retracted, the legs are swung 90 degrees in the other direction. That takes all the guess work out of it.---Foot pedal controls for the type of valving you need are available--Brian

Black Forest
08-18-2010, 02:10 PM
Danke Brian,

This afternoon I "jury rigged" up a cylinder. I used a 5/3 valve with a closed center to test. It worked OK and I could stop the leg restraints where I wanted. That was good. But the actual mechanics of the best way to mount the cylinder I have not got yet. I used a trunion mount on the cylinder and mounted the rod end of the cylinder just about the pivot point. I am looking for a more efficient method for the linkage.

brian Rupnow
08-18-2010, 02:36 PM
Post a picture---I can probably help.---Brian

Black Forest
08-18-2010, 03:27 PM
Here is a rough sketch of the rear leg restraint concept. The actual leg restraints in use Brian you have seen the picture. It is posted in this thread.

http://i853.photobucket.com/albums/ab91/burnandreturn/leg_restraint_pivot.jpg
http://i853.photobucket.com/albums/ab91/burnandreturn/Still0704_00003.jpg

brian Rupnow
08-18-2010, 04:17 PM
I would recomend using the longest cylinder you have available. Move the point where the rod attaches to the frame as far away from the pivot as possible. You don't want to give the sheep a whiplash. Use a cylinder with a clevis mount on the rear of the cylinder body. as the cylinder extends it will rotate about the pinned connection at the rear of the cylinder body.

Black Forest
08-18-2010, 04:23 PM
I used a trunion mount on the cylinder because I thought it would work better on the angles. I agree with the whiplash! Do you see a solution to get a true 180 degree's? That is my biggest block right now.

Black Forest
08-18-2010, 04:30 PM
I used a trunion mount on the cylinder because I thought it would work better on the angles. I agree with the whiplash! Do you see a solution to get a true 180 degree's? That is my biggest block right now. I will have electrical power available. Would there be some other mechanism other than an air cylinder? A three phase motor is no problem. I say that because of the start stop and instant reverse. We have three phase everywhere this thing would be used.

brian Rupnow
08-18-2010, 05:46 PM
An air cylinder properly set up with flow controls on the exhaust is the cheapest way. Two air cylinders mounted back to back as I originally suggested is the best way to go----No worrying abot "home" positions then. Center of arc is always the natural "home" position. Foot pedal can be a rocker type. Foot not on it, it defaults to home position. Foot on one side of pivot, it rocks 90 degrees away from you. Foot on other side of pivot---It returns to default position and then rocks 90 degrees towards you. Take foot off--It defauults to home position at center of arc. It It could be done with gearmotors and ballscrew ---uber expensive. Could also be done with reverseable gearmotor and roller chain with limit switches.

Black Forest
08-18-2010, 06:17 PM
I understand what you mean with the two cylinders, I think! What I still don't get is how you get it to go 180 degree's. If the cylinder(s) pushes until the arm is now 90 degree's from vertical and the cylinder is now parallel to the arm there will be a straight pull back when I go to bring the arm back to vertical. If I raise the back end of the cylinder that will work when I extend the cylinder but then it will not go all the way down to horizontal when I retract the cylinder. I don't know how to overcome the straight pull or push of the cylinder.

The Artful Bodger
08-18-2010, 06:28 PM
Black Forest, good to see you are continuing with this Holy Grail for shearers everywhere!

I know you are tending towards air cylinders etc but I suggest you consider a geared electric motor, one of those with a right angle worm reduction on the end, then you could use a fwd/rev switch to control and even get more than 180 degrees if required.

John

Black Forest
08-18-2010, 06:44 PM
This crude drawing shows the cylinder lined up with the arm. If I would retract it now it would just pull straight back. If I elevate the back of the cylinder it would retract but then the arm would not go down all the way.
http://i853.photobucket.com/albums/ab91/burnandreturn/legrestraintframe2.jpg

Black Forest
08-18-2010, 06:47 PM
I like the idea of a gear motor with roller chain.

Black Forest
08-18-2010, 06:53 PM
what about an air motor with roller chain. Easy foot pedal operation for CW or CCW rotation. Not complicated to implement. I will have to have air available for the other functions such as the tipping crate.

Black Forest
08-18-2010, 07:24 PM
What about a cross arm on the bottom with a cylinder at the end of each arm. When one cylinder would push the other would free flow so as not to oppose each other.
http://i853.photobucket.com/albums/ab91/burnandreturn/legrestraintframe3-1.jpg

brian Rupnow
08-18-2010, 08:31 PM
Damn---I knew I was right!!! I just had to put my geometry hat on for a while. Two equal length cylinders, just like I said. Gives3 "absolute" positions.
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSYSHEEPTIPPERMECHANISM.jpg

Black Forest
08-19-2010, 03:38 AM
Brian,

Your last drawing with the two cylinders will not move the arm 180 degree's.

The must rotate 180 degree's. Unless I am missing something.

brian Rupnow
08-19-2010, 09:49 AM
Two questions--why is 180 degrees so critical, and do you need a "home position" at the vertical position.

Black Forest
08-19-2010, 11:07 AM
I need 180 degree's in order to roll the sheep enough to get to it's backline or a little more even. If the feet don't go low enough it is a problem to shear the sheep. The pivot point of the hind leg clamps needs to be higher than the backline of the sheep. On an axis down through the middle of the sheep.

Black Forest
08-19-2010, 11:10 AM
I need 180 degree's in order to roll the sheep enough to get to it's backline or a little more even. If the feet don't go low enough it is a problem to shear the sheep. No actual home position is needed. That can be done manually with the foot pedal.

brian Rupnow
08-19-2010, 11:25 AM
Okay--I'm running out of options that don't get into big money. One other option that will work is to use 2 cylinders back to back with one rod end fixed in place with a clevis mount to the frame of the machine, the other rod end attached to an endless loop of roller chain, almost parallel to the run of the chain. The roller chain passes over one large sprocket which is on the rotary axis of your tipper, and there would have to be 2 or 3 idler sprockets to run the chain around so that it makes an endless loop. It would take a bit of calculation, but you could set it up so that when one cyl. is extended and one is retracted, the tipper is in its "home" position. When both cylinders are extended, it pulls the chain around the sprockets and tilts the shearing platform fully in one direction. when both cylinders are retracted, it swings the shearing platform gully in the opposite direction. This still allows the use of flow controls to govern the speed, and still gives 3 discrete positions.

Black Forest
08-19-2010, 12:30 PM
You will have to imagine a chain running around the sprockets. The cylinder could be attached to the chain on the straight bottom run. With the cylinder half way extended the arm would be vertical. extend the cylinder and the chain would be moved in that direction and rotate the arm one way. Retract the cylinder and the arm would go the other way. I didn't get why I would need two cylinders. I need to be able to stop the pivoting arm any where I want. Not just have three positions. What am I missing?

http://i853.photobucket.com/albums/ab91/burnandreturn/legrestraintpivot.jpg

brian Rupnow
08-19-2010, 01:07 PM
Because you don't want to have to make a judgement call each time you return it to a vertical position. A single cylinder will only give 2 "absolute" positions. Either all the way retracted or all the way extended. This means that you will have to watch things all the time and try to be quick enough on your foot pedal to position the tilting bed vertical each time the cylinder is at half stroke, which will be a royal pain in the ass. By using two cylinders tied together as I promote, you get 3 "absolute" positions. One for vertical---one for tilt away from you, and one tilted towards you.--No guesswork involved. The normal "home" position can be any of the 3.

Black Forest
08-19-2010, 01:12 PM
Are you then able to stop the pivoting arm anywhere you want or does it just go to those three positions?

Black Forest
08-19-2010, 01:14 PM
I can't picture how you would use the two cylinders. You must use a different concept of the chain.

brian Rupnow
08-19-2010, 01:21 PM
Are you then able to stop the pivoting arm anywhere you want or does it just go to those three positions?
That depends on how your valving is set up. If the valves are set up to deadhead the air when you want to stop at some intermediate position, I suppose it is possible. Air cylinders are not a good thing to use if you want to make a number of intermediate stops at anywhere on the arc. in that situation, go with a reverseable gearmotor driving the roller chain. Air cylinders are really only intended for "full stroke" applications. The other things about air cylinders is that they have this horrible tendancy to "stick" if there is any hard friction points in the mechanism they are moving--Then they build up pressure to a point where they overcome the friction point and let go with a bang---and shoot your sheep out though the side of the barn!!!

Toolguy
08-19-2010, 01:23 PM
Then it would be a Ramapult instead of a Catapult.

Black Forest
08-19-2010, 01:30 PM
Ramapult.....Toolguy, have a beer.

I think the gear motor might be a better solution.

Toolguy
08-19-2010, 04:06 PM
Great idea - I just went and got one. I like the gear motor idea. Might want to put limit switches on each side so you don't dump them on the ground by accident.

The Artful Bodger
08-19-2010, 06:58 PM
I keep having these non-constructive ideas for variations and alternatives including one that I weigh at least as much as most sheep and I think a bit of doodling in front of TV one evening could lead to a design where I used my weight to roll the sheep. No motors involved.:rolleyes:

brian Rupnow
08-19-2010, 07:27 PM
If you want to stay with a pneumatic rotary actuator, use this offering from SMC. It has an internal gear rack and can go a full 190 degrees if you need it. I would go with the largest unit. All you need is a solid place to mount it and a coupling between the output shaft and the rotary center on your table.
However---If you want to stop the rotating table at anywhere in the arc and LOCK it in position, use an electric gearmotor with an internal "Stearns" type brake. This is a drum or disc type of brake built into the motor that is always "on" except when electrical current is flowing to the gearmotor. That way your table won't try and run away from you when you are holding one hand on the sheep and one hand on the shear.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SMCPNEUMATICROTARY190DEGREEACTUATOR.jpg

Black Forest
08-29-2010, 08:08 AM
I am waiting for my parts for the gear motor to get here. So I was thinking why couldn't I do it with two cylinders with a chain over a sprocket with one extending and one retracting to facilitate pivoting the leg restraints. This would be easy to build. What am I missing?
http://i853.photobucket.com/albums/ab91/burnandreturn/SimLab_63.jpg

brian Rupnow
08-29-2010, 08:40 AM
It is almost impossible to get two cylinders to travel at the same speed. Even if the cylinder being "pulled" had both ports open to atmosphere, as soon as the center of gravity of your leg restraints passed over the 'high point", then gravity would make it "fall", and there simply isn't enough reaction time in a system to suddenly reverse the valving so that the cylinder being pulled suddenly becomes the cylinder being extended under controled power to let out chain while the cylinder which was originally doing the pulling is now being "pushed by the chain. (you can not push a chain). To make that system work, you would need double ended cylinders with a second set of sprockets and chains from the other rod ends. Chains don't do well in an "overturning load" situation.

Black Forest
08-29-2010, 10:05 AM
I think you are right of course Brian! The metering of the air would definitely be difficult to get just right. Hydraulics would be much easier. I am now waiting on the sprockets, chain and switch to use with my gear motor.

Another question! Would a scissor lift type of mechanism or a forklift type of mechanism be a better solution to lifting my crate with the sheep in it to be tipped? The picture you posted Brian about the lift you designed got me to thinking about a scissor lift. If I did not have power available I would use the circular tipping system. But whereas I do have power available I would like to keep it as compact as possible. I would like to stay away from the sheep having to go up a ramp.

brian Rupnow
08-29-2010, 11:10 AM
A scissor lift would work to elevate the sheep. However, if you did that, you would have to have the squeeze and tilt mechanism attached to the scissor lift top platform. Problem is, on most scissor lifts the top is hinged on one end and held in place by gravity at the other end.---Meaning of course, that the tops are not designed to accomodate any uplift forces. So you could elevate the sheep fine, but as soon as you tipped it 100 or 115 degrees to position the sheep for pulling it into your "shearing" position, all Hell would break loose.
I know I could design a ground level squeeze and tilt that the sheep would walk into at ground level, then the squeeze would restrain the sheep, then it would rotate and position the sheep at the exact angle and height you wanted, ready to be slid down into the shearing position. The squeeze would probably require two short stroke air cylinders, about 2" dia. x 6" stroke, and the tilt would require one 4" dia. air cylinder with about a 18" to 24" stroke.
----And a word of caution---On the tilt mechanism that tilts the leg restraints, I assume you want that thing to stop and hold position while you shear the sheep---not be moving because of the struggling of the sheep or any outside forces which you apply to the mechanism as you do your shearing, or the coasting of the motor. That is why I mentioned in previous posts that the motor needs an automatic Stearns type brake that comes on any time power is not being supplied to the motor.---Also, the leg restraint tilt mechanism needs a "home" position. You don't want to have to manually reposition it to the correct position every time you release a sheep from the leg restraints. I would tie in a set of limit switches so that when the squeeze/tilt/elevate system was energized, the leg restraint tilt mechanism would automatically return to its "home" position, ready to receive the next sheep.

Black Forest
08-29-2010, 11:33 AM
The gear motor I bought has the brake.

I thought of the tilt mechanism from the ground. I really don't need to elevate the sheep and the tilt. I could just tilt the box with the sheep squeezed.

brian Rupnow
08-29-2010, 12:17 PM
This is what I had in mind----
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSY-SHEEPTIPPER.jpg

Black Forest
08-29-2010, 12:57 PM
That is basically what I had in mind. The problem is the sheep needs to be brought up higher and tipped so it almost falls into the shearing cradle. That is why I was thinking along the lines of a forklift arrangement. The lifting and tipping cylinders would be one in the same. A track on the front closest to the human. Then two cylinders on the outside back corners. As the cylinders extend the crate raises vertically. When it comes to the stops on the front the cylinders keep going and that causes the crate to tip. The back side would have and angled track to keep the crate from tipping too soon while it is raised.
The front pivot point of the crate reaches the stops and as the cylinders keep extending it causes the tipping.

As soon as the sheep is released from the squeeze it will try to stand up. If I have to slide it to far I foresee some struggling. A sheep flopping around is not a good thing for me or the sheep.

brian Rupnow
08-29-2010, 01:19 PM
As long as you keep the pivot high on the side of the stall as I have shown it, you can tip the sheep damn near upside down if you want to, with only one cylinder hooked to a lever at one end of the pivot.

brian Rupnow
08-29-2010, 02:40 PM
There is a danger in combining two movements from one cylinder. You are no longer able to control the speed of two seperate events. You will want the cradle to rise quickly. However, you will certainly want to slow things down a bit when the tip comes into play (Think Ramapult). If your set up is going to be "fixed" as opposed to "portable", set 4 steel guidepipes into the concrete floor and put a slightly larger pipe on each corner of a platform which will fit over the guide-pipes. I can't see you needing anymore than 42" of vertical travel, so dig a pit in the floor and cement in a "well" and mount the base of your vertical lift cylinder into the concrete at the bottom of the well, same as old time automotive garages had. Sheep walks into stall mounted on platform at ground level, gates come down at each end so sheep can't run foreward or backward, squeeze comes on to further immobilise sheep, vertical lift cylinder extends and the entire platform/stall rises as high as you think you need it. Then the tip mechanism comes into play (It will be attached to the guided platform). Any "overturning moment" load imposed on the platform will be balanced/compensated for by the 4 guide pipes which are set in the concrete floor. One central cylinder required for lift, probably two short stroke cylinders as mentioned earlier for "squeeze", and one cylinder required for the tilt mechanism. All cylinders and "sets" of cylinders can be flow controlled seperately to govern the speed of each operation, each cylinder should be "cushioned both ends", and with cylinder mounted reed switches, a very simple PLC can do the sequencing.

Black Forest
08-29-2010, 03:22 PM
I do want to have it portable.

The Artful Bodger
08-29-2010, 03:37 PM
As soon as the sheep is released from the squeeze it will try to stand up. If I have to slide it to far I foresee some struggling. A sheep flopping around is not a good thing for me or the sheep. I agree.

BTW, I see more concepts for tipping the sheep sideways into the shearing cradle but of course the human shearer never does that. How about this line of thought?

Sheep walks onto a turntable which has sides and a gate which closes in front of her, we will call this the sheep carrier. Then you hook a strap, something like the webbing of a car seat belt, across behind her. Turn the turntable 90 degrees, this is a horizontal movement and will likely not need to be powered.

You will have found by previous experimentation where the centre of gravity is of a typical sheep and the sheep carrier will be horizontally pivotted at that point. Now upend the sheep carrier, using power if necessary, and tip the sheep backwards, supported by the strap across her bum, to dump her on her back on the shearing table. A short hiss of compressed air or a heave on the handle and she will be lying four feet in the air with an astonished look on her face waiting for your to clap on the leg irons!:)

The Artful Bodger
08-29-2010, 03:42 PM
I do want to have it portable.
Maybe the turntable is not such a good idea then..:(

brian Rupnow
08-29-2010, 03:48 PM
Same deal as previous picture---higher pivot point.
http://i307.photobucket.com/albums/nn294/BrianRupnow/ASSY-SHEEPTIPPER-1.jpg

brian Rupnow
08-29-2010, 03:55 PM
How about this---Sheep takes run at springboard, does 180 degree flip, lands on back on shearing table.???
http://i307.photobucket.com/albums/nn294/BrianRupnow/springboard.jpg

Black Forest
08-29-2010, 04:14 PM
Brian, The sheep will have to slide too far after the squeeze is released if we do it with the higher pivot point. The higher the pivot point the more the sheep will have to slide after the squeeze is released.

brian Rupnow
08-29-2010, 04:48 PM
I can only assume that the more seperate motions there are, and the longer it all takes, then the more agitated and alarmed the sheep is going to be. I don't think its a good idea to have one motion that elevates the sheep, then stops, then rotates the sheep. I think you want whatever happens to be one relatively short, continuous movement. We seem to agree in principle that having the pivot on the side of the stall, part way up the side is probably the simplest place to have it. If the pivot is on the bottom of the stall, then it has to be lifted unnecessarily high before it can be tilted to let the sheep slide out at a proper working height for the shearer. I understand your reluctance to go with the first design I posted today, because if it tipped the sheep almost upside down, the side of the stall opposite from the pivot would be in the way when you went to pull the sheep out. There is another possible way, but I am not going to make a drawing of it. In both of the drawings I posted, the pivot point on the shearing table was at a fixed height from the floor. However---If the pivot point on the shearing table was fixed to a mechanism that lifted the pivot points through a distance of 15 or 18 inches as the stall was rotating, it would all be one continuous movement with no "stops" along the way. I have used this type of mechanism in the past, where the two "pivot points" seperated by a distance of 48" or so had to both rise up at exactly the same speed and travel the same exact distance. This was accomplished by having the two "pivot points" attached to vertical gear racks. A horizontal shaft with two matching pinions, one at each end of the shaft serves to tie the movement of the two racks together and travel exactly at the same speed and distance. The shaft was turned by a gearmotor.

Black Forest
08-29-2010, 05:20 PM
What do you think of this? This is the four posts with a sliding crate but instead of one cylinder buried under the bottom of the crate. I put two cylinders on the ends to lift the crate. Then have a separate tilting box with the squeeze. You can't see it too well in the picture but there is a box that slides up the tall pipes. The cylinders need to be either at the back or the front to allow a sheep to walk through the crate.
http://i853.photobucket.com/albums/ab91/burnandreturn/SimLab_67.jpg

brian Rupnow
08-29-2010, 05:31 PM
I thought of that, but the drawback to it is that its dammed near impossible to get 2 or more cylinders to extend evenly at the same time. Due to "stiction" (Sliding friction) in the seals and o-rings one cylinder always gets ahead of the other and then the mechanism binds and jerks. Hydraulics are marginaly better than pneumatics because you can get hydraulic flow dividers, but even then its not 100%. Of course, the system I mentioned in the previous post using racks and pinions could work here as well. That way you can use one gearmotor to drive all the vertical movement. The cost of racks and pinions is quite low.

brian Rupnow
08-29-2010, 05:33 PM
I just seen your edited post---I think you would want the two cylinders on opposite diagonal corners to balance things a bit.

Black Forest
08-29-2010, 06:01 PM
So instead of using cylinders a rack and pinion with a gearmotor. I am trying to visualize how the racks would get mounted. If I would put a scissor lift under the crate I have posted why wouldn't that work. One side could be fixed and the other could roll. The frame on the vertical posts would keep it stable.

brian Rupnow
08-29-2010, 07:34 PM
Yes, a scissor lift under the rack would work. On the system I designed using racks, the racks had V-groove wheels on each side at each end and were guided inside vertical angle irons.

Black Forest
09-01-2010, 04:42 PM
I am making progress on the lifting and tipping mechanism.
http://i853.photobucket.com/albums/ab91/burnandreturn/SimLab_88.jpg

The Artful Bodger
09-01-2010, 04:48 PM
A lot of thinking and effort going on here but do you guys think the project might be getting a little over complicated?

Black Forest
09-01-2010, 04:50 PM
What makes you say that? I am trying to keep it as simple as possible.

The Artful Bodger
09-01-2010, 04:52 PM
What makes you say that? I am trying to keep it as simple as possible.

It look too complicated to my eyes, now I must think of a simple alternative and present that! Time for me to do some serious thinking!:)

Black Forest
09-01-2010, 04:56 PM
I have two single acting air cylinders on the way. The spring will extend the rod and air will retract the rod. That way I can use the two cylinders to rotate the leg restraint pivot arm. I will at least try it and see. The engineers at Festo told me if that doesn't work they will send me a rotary actuator to try.

At least I am learning a lot of new things!

brian Rupnow
09-01-2010, 05:09 PM
Looking good!!!!----Brian

The Artful Bodger
09-01-2010, 05:11 PM
http://farm5.static.flickr.com/4127/4949430098_eda41a33b3.jpg

Thats my present line of thinking....once the sheep is on her back you clamp on the leg restraints and start shearing.

It needs a bit of thought to get the balance points so that it is not too difficult to tip her over and I think the sheep would have to be above floor level at the start and the operator might have to stand on a step to do the tip.

Black Forest
09-01-2010, 05:19 PM
Here is a view with the chute tipped. It is not so complicated really.

http://i853.photobucket.com/albums/ab91/burnandreturn/SimLab_89.jpg

Black Forest
09-01-2010, 05:24 PM
Thank you Brian. Please excuse my trashy renderings but I just pick contrasting metals so as to see the individual parts. I have a real appreciation for the designs you post here Brian. It takes me a long time to do a very simple thing in the CAD program. But I must admit I might get addicted to working in 3D Cad. It really does open up a different world.

Black Forest
09-01-2010, 05:41 PM
AK, I want this machine to be as easy on me as possible. I don't want to say money is no object but I am willing to invest in this project. I like it and I want to try to build the ultimate shearing machine. I don't want to make too many compromises without getting ridiculous. It is a journey also if you know what I mean. I am having to learn so many different things. There will be a lot of machining to do when I have the final plan. That will be a great time for me to learn so many different aspects of building this machine.

Black Forest
09-05-2010, 02:43 PM
I modeled this crate with the hinges and air cylinders to tip it. Only I am not sure what I am missing? I have the pivots so they can move some as the cylinders extend. I did that in order to lover the whole crate a little as it is tipped. Might not be necessary. Any idea's?

http://i853.photobucket.com/albums/ab91/burnandreturn/tippingcrate_only2.jpg

Evan
09-05-2010, 02:54 PM
I haven't been following this thread because it grew too long while I was busy with fire preparations. However, at first glance at this apparatus I want to know what sort of drugs you are going to give the sheep. :D

I have seen lead sheep balk at stepping over a garden hose because it thought it was a snake. Finally the first one takes a big jump over it and all the rest do the same even though they never had time to see it.

Black Forest
09-05-2010, 03:08 PM
No drugs Evan! That is why there is a decoy sheep at the end of the chute. The other sheep see the decoy and go through. It actually really does work. Of course my sheep are very well adjusted and practically roll over on their backs and rub up on the shearing head!!!! I use long races and have the sheep approach the machine in two narrow races that funnel down to one right at the machine. The sheep are used to go through the races. Also that is why I want the sheep to not have to go up a ramp. I want them to stay almost at gound height until the are in the squeeze chute. Easier to get them to go through. My Border Collies do the job of keeping the sheep coming up the races.

steverice
09-05-2010, 04:40 PM
I thought the best way to shear a sheep and perform other functions was to simply put the hind legs in the tops of your knee high boots.

http://i17.photobucket.com/albums/b91/riceburnerfb1/motorcycle/706px-Ewe_sheep_black_and_white.jpg

brian Rupnow
09-05-2010, 05:03 PM
ArtfullBodger---I really like your drawing!!!! I'm not sure about the mechanical soundness of it, but it gave me a big smile!!! BlackForest---What you have designed is an unequal leg 4 bar linkage. This type of mechanism will yeild some truly astounding results, but again, it can be a total Bitch if the two sets of pivots and two cylinders operate totally independent of each other---and the farther apart they are, the worse it becomes. Can you make animations of the action with the software you are using? The system itself works fine. The problem comes from the two cylinders wanting to extend at two different rates of speed---Everything gets all cocked off at an angle when that happens. Better to use one large bore cylinder on center if possible.----Brian

The Artful Bodger
09-05-2010, 05:27 PM
ArtfullBodger---I really like your drawing!!!! I'm not sure about the mechanical soundness of it, but it gave me a big smile!!!

The mechanics may need some tweaking but I am confident that it is an easy way of getting a sheep on her back.

Black Forest
09-05-2010, 05:47 PM
Brian, I can only drag the parts in the design window. I can pivot it back and forth. I have grabbed the end of the cylinder where it attaches to the crate and moved the crate up and down. It seems to work fine but I am not sure in real life it will work. Are there any rules regarding this linkage to go by?

brian Rupnow
09-05-2010, 06:04 PM
Brian, I can only drag the parts in the design window. I can pivot it back and forth. I have grabbed the end of the cylinder where it attaches to the crate and moved the crate up and down. It seems to work fine but I am not sure in real life it will work. Are there any rules regarding this linkage to go by?
Not really any rules, other than obvious mechanical interferance. Can you save the models as a .step, .stp, or .iges or .xt or any other kind of exportable file? If so put them into a .zip file and send them to me. I will model it and animate it for you.---Brian

ligito
09-05-2010, 06:27 PM
I can hear a loud clap, clap sound.

brian Rupnow
09-05-2010, 06:54 PM
I take it back!!! After a carefull look, I see that its not a 4 bar linkage. My Bad. What you have shown is a simple single pivot device. It will work fine.

brian Rupnow
09-06-2010, 04:05 PM
Blackforest---Your files came though and opened fine with Solidworks. I just measured the outer diameter of the cylinder as being 1.9685" (50 mm) in diameter---does that agree with what you have? Please send me the maximum and minimum center to center between cylinder pins, and if you can, the part number from Festo. And---my first take on this seems to have been correct. It does look like a 4 bar linkage with two "fixed" pivots and two "floating" pivots.---Brian

Black Forest
09-06-2010, 04:19 PM
Brian, I don't have a part number from Festo becaue I don't know until I get my dimensions what cylinder I will need. I have cylinders here that go from 150mm to 1250mm.

And yes 50mm is correct.

brian Rupnow
09-06-2010, 04:45 PM
Okay---Here we go. The light blue part which I designed is "fixed" and can not move. Don't worry about the shape of it for now---Its just that I need an "anchor" to attach all my other parts to. As I said earlier, this is a 4-link with two fixed pivot points---and they are the two pivot points in my blue coloured part. First observation is that you need something for the bottom of the tipper to 'bottom out" on, otherwise it will just keep on moving on the pivot points untill it hangs straight down as in the second picture. I am going to make the assumption that the crate is going to bottom out in the lifting frame, and that when it is bottomed out, the bottom of the crate is going to be horizontal, as shown in the first picture.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SHEEPTIPPERHORIZONTALBOTTOM.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/TIPPERFALLENUNDERITSOWNWEIGHT.jpg

brian Rupnow
09-06-2010, 04:50 PM
Nope, it isn't going to work with 4 pivot points--It will flop all over the place, especially after it begins to tip the sheep past horizontal. You will get a reversal effect from gravity and the sheep and tipper will collapse in a heap. I am going to continue with this, but assume the two link arms are welded to the crate and can't pivot.

Black Forest
09-06-2010, 05:07 PM
Brian, The top pivot arm I was going to mechanically limit its movement. The only reason for the pink arm at all is to move the crate holding the sheep back away from me a little and to lower it overall some. But it is not absolutely necessary to have the pink pivot arm at all. I could just use a simple pivot point and set the whole crate lifting part back away from me by the same amount as the pivoting arm would provide. ????

Just out of curiosity do you use a 3D mouse with your CAD program?

brian Rupnow
09-06-2010, 06:07 PM
Will this work for you?--Everything is a lot more stable when we go from a 4 link to this configuration with only 3 pivot points.http://i307.photobucket.com/albums/nn294/BrianRupnow/TIPPERASSY-BRIAN.jpg

brian Rupnow
09-06-2010, 06:10 PM
I just use a conventional 2 button mouse with a scroll roller on top.

brian Rupnow
09-06-2010, 06:19 PM
Bruce---I got your second file, but trust me, the fewer linkages you have, the better this thing will work. First thing to establish is what your limiting factors are. #1--Is 8 degrees as shown enough tip? #2--is the position of the lower cylinder mount acceptable in terms of position relative to the tipper body. #3-It complicates things considerably if you try and move the tipper sideways as you tip it. Do you really need to do that. All it does is complicate things a lot for a minimal gain in real estate.

Black Forest
09-06-2010, 06:20 PM
Yes that will work. I just sent you an E-mail with an attached stp file.

I asked about the mouse because I use a 3D connexion Space Pilot Pro and it really helps me to position the models much easier.

It is used in conjunction with the normal mouse. So I have a mouse in each hand with the keyboard in the middle. I like gadgets!

Black Forest
09-06-2010, 06:23 PM
The only problem I see with this set up is it starts to get difficult to get the crate minimal distance from the ground with the cylinder mounted so low.

brian Rupnow
09-06-2010, 08:02 PM
http://i307.photobucket.com/albums/nn294/BrianRupnow/secondtry.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/secondtry-ISOMETRIC.jpg

brian Rupnow
09-06-2010, 08:10 PM
http://i307.photobucket.com/albums/nn294/BrianRupnow/secondtry-ORTHOGRAPHIC.jpg

Evan
09-06-2010, 10:02 PM
I see a major issue. The cylinders need to be well out of the way of the ends of the cradle. If they aren't sure as heck some sheep will end up with it's head caught or a leg broken. You also need to consider what may happen if it squirms around and ends up a leg sticking out through the framework.

Black Forest
09-07-2010, 07:43 AM
Not to worry Evan! The crate that the sheep walks into is completely enclosed. In these drawings the skin is not in place and the crate is long enough so no body parts hang out.