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34Ford
06-25-2009, 07:32 PM
Am looking for a rotary table about 8" or 9" in dia. This would be used on my Bridgeport and used to mill radii in aluminum. For a rotary table to be used for milling what should I be looking for in a used unit. Are some rotary tables designed strictly for indexing and not capable of being used for milling?
Thanks

philbur
06-25-2009, 08:25 PM
If the thing is only good for indexing it is called an indexer and doesn't normally have a table. Indexing on a rotary table is usually an add-on so would be considered a plus. The issues are do you want vertical, horizontal or both, the weight with regard to easy of lifting and of course the quality - used Western or new Asian. As rotary tables are genrally considered "useful even if I never use it" used tables in good condition are not that hard to find, so there should be no reason to take a gamble on a highly dinged-up example. Even so they are a robust piece of equipment and in manual form will have worn out the user long before the user wore it out.;)

Phil
:)


Am looking for a rotary table about 8" or 9" in dia. This would be used on my Bridgeport and used to mill radii in aluminum. For a rotary table to be used for milling what should I be looking for in a used unit. Are some rotary tables designed strictly for indexing and not capable of being used for milling?
Thanks

Frank Ford
06-25-2009, 09:44 PM
For what it may be worth, I suggest you consider a ten-inch table. When I was looking for a rotary table for my 9 x 42 mill, I thought 8-9" would be just fine. I ended up finding a nice looking one on eBay - a Yuasa ten-inch. When it arrived I knew it was too big and heavy.

Well that all changed in a really short while. Now, I'd consider 10" a minimum - and I don't do big work. In fact, I just made a 12" fixture plate for it to expand my clamping area:

http://www.frets.com/HomeShopTech/Projects/RotabFixturePlate/rotabfixtureplate22.jpg

Here's a little article about making that plate, and how I use it:

http://www.frets.com/HomeShopTech/Projects/RotabFixturePlate/rotabfixtureplate.html

nheng
06-25-2009, 10:22 PM
Geez Frank, you do nice work, both tooling and instruments !

34Ford, I've been in the market for an RT for a while also and have a nice 10" Yuasa available near me. While Frank is right about the size, you also need to consider if the RT weight is in line with your lifting and moving abilities.

Of course you can get around this, and many have, by either rigging up a lifting arm that pivots or by storing it on a rolling cart that you match to the mill's table height so it can slide on and off.

Den

toastydeath
06-25-2009, 11:24 PM
It's surprising how big a rotary needs to be to hold stuff. The tables on our CNC horizontals are 12", and they can't hold much. We have one 20" horizontal, that seems to hold most things by a large enough margin. Although, rotaries on a horizontal need to be a bit larger to hold the same part than they do for a vertical mill.

We have several 12" and 18" tables for the manual machines, with large faceplate just like Frank's - one of the faceplates is actually just a big (~24") square somebody drilled holes in.

We don't do terribly large work, either, it's just easy to underestimate how much machine real estate you're going to need to do a job without having to jury rig a solution. Which may be okay if you're not going to use it much.

The one thing that would be really nice to have that we don't is a ~6" rotary with a pair of 3/4 jaw chucks. I just don't see a 8" or under of faceplate being much use. I kind of notice that unless we build a special fixture to hold a part on a small table drilled explicitly FOR that table, you need about 2"-3" around the part to get clamps on it. So if you have an 8" table, things over 3" or so may be difficult to get clamped to your satisfaction while maintaining easy clearance around the things you want to machine.

lenord
06-26-2009, 01:23 AM
I'd vote for a 10" or bigger too.

If you need to make a larger top plate, you can get Mic 6 aluminum plate round drops from sandsmachine.com for a fair price. The sizes go up to 18.5" OD x 1" thick if I recall correctly. Good plate for a decent price.

You may also consider getting a large DC servo motor with a gearhead to turn the RT. A cheap dc motor controller will give you varable speed. Cranking gets old quick.

You can index on it, it is just a bit more time consuming.

FWIW
Lenord

Paul Alciatore
06-26-2009, 02:09 AM
I have a 10" and I feel it is perhaps the best compromise between capacity and weight. It is just about at my limit for lifting and I make a point of never doing so with greasy/oily hands less it get away from me.

I have clamped 7"+ diameters on it and feel I could easily go to 8". I have seen some outboard clamps that slide into the tee slots for clamping up to the full diameter of the table or even a fraction more, but I don't have any so haven't tried them. Of course, if you drill mounting holes in the workpiece, you can mount anything that will clear the mill's column.

I have milled arcs on it without any problems.

Unless it's a real lightweight, I think a 12" or larger would defenitely require some kind of crane or hoist.

Walter
06-26-2009, 03:46 AM
I run a Phase II unit (http://www.use-enco.com/CGI/INSRIT?PARTPG=INLMKD&PMPXNO=954014&PMAKA=200-1915) and I'm pretty happy with it, I do have a 16 inch faceplate that has been adapted to fit on for larger stuff. Try to get something that allows both horizontal and vertical use, you wont regret it. The big drawback to this particular unit is it's 180 lbs and it's a bit of a strain to move. I honestly wish I also had a super spacer, most of the time a unit like that would cover most of my projects, but the tilting table on the Phase II has been invaluable thusfar. Most of my work is tool and die, and I make some pretty odd stuff, honestly I can't say that I'd otherwise ever have had a need/use for the tilting table.

abn
06-26-2009, 03:53 AM
There are a few Rotary Tables that are only good for indexing (I have an OMT table like this)...Basically if it has a crank or a motor on the side you should be good to go.

BadDog
06-26-2009, 04:17 AM
I have what I think is about the perfect minimal setup, at least for my needs.

Ultimately, if the capacity is needed, I have a 12" Troyke V/H that is in very good shape. But it weighs somewhere close to 200 lbs. It takes me an my son to get it on the table, and I don't have room to keep it on a die-cart or the like. I recently got s Sky Hook, so that should be changing, and I suspect it will get a lot more use then.

I also have a relatively light weight 8" horizontal that I use for most all occasions where it will suffice. It only weighs about 50 lbs, and is a LOT easier to deal with.

oldtiffie
06-26-2009, 04:47 AM
Am looking for a rotary table about 8" or 9" in dia. This would be used on my Bridgeport and used to mill radii in aluminum. For a rotary table to be used for milling what should I be looking for in a used unit. Are some rotary tables designed strictly for indexing and not capable of being used for milling?
Thanks

Here is a link for "Vertex" rotary tables which as far as I can gather are the same as the US-sold "Phase 11" tables. They are excellent quality from my own experience. I have the 6" and 8".

Size and weight will be big considerations:

My 6" and 8" on my HF-45 square column mill - for scale:
http://i200.photobucket.com/albums/aa294/oldtiffie/HF-45%20Mill%20misc/HF45-5.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/HF-45%20Mill%20misc/HF45-1.jpg

And here is the link to my suppliers page for rotary tables (just click on any one for detail/spec/data information).

Cost conversion: AU$1 ~ US$0.80

https://www.machineryhouse.com.au/Products?stockCode=R012B

Carm
06-26-2009, 09:51 AM
Frank Ford, I enjoy reading your articles, admire luthiers and consider you crackerjack in all you attempt.
But I'd feel better if you substituted a DTI for the upside down endmill used as center locator. More accurate to sweep the hole, and saves edges on the cutter.
.02

lenord
06-26-2009, 12:30 PM
Is that a vise I saw bolted to the rotary table ?

I had never thought to do that for the small parts that just need an arc or something. Thanks for posting that picture !

Lenord

Frank Ford
06-26-2009, 01:00 PM
Carm -

No doubt you are right about sweeping the hole for greater accuracy. Fact is, most of the stuff I do is rather "offhand" so I get away without some of that standard good technique.

I'm still influenced by all those little tricks I've learned in a lifetime of wood working, and sometimes I can't resist applying them as I machine metal. Gets me into trouble often enough, for sure!

I've never been a perfectionist, I guess. In my business (restoring stringed instruments) I've seen so many practitioners fail to succeed because they couldn't call a job "done," but had to keep chasing details as the time sped by. So, I do spend a fair amount of energy keeping focused on the clock as I work.

In fact, I had an engraved name tag made for myself to wear at our luthier conventions:

http://www.frets.com/ForumPix/mrgoodenoughwrench.jpg

Oh, I forgot to mention that I use an old end mill for locating the hole. It's one of those I really burned up trying to make it cut better by pushing harder. Hey, it works with wood. . .

oldtiffie
06-27-2009, 01:07 AM
http://i200.photobucket.com/albums/aa294/oldtiffie/HF-45%20Mill%20misc/HF45-1.jpg

Is that a vise I saw bolted to the rotary table ?

I had never thought to do that for the small parts that just need an arc or something. Thanks for posting that picture !

Lenord
Thanks Lenord.

Yes it is. It is a set-piece set-up to show the amount of "head-room" on my mill. But to be honest, I'd set it up on my 8" rotary table. It is very easy to set the off-set from the rotary table just by rough-setting the vice on the rotab and then "fine-tuning" it with "packers" as required on the face of the vice jaws.

I will show some other set-ups with and without rotary tables later. I had it all but done - a couple of hours - when I closed the wrong window/session!!! But I will try to repeat it later.

philbur
06-27-2009, 06:15 AM
My experience is that rigidity goes down very quickly when you stack work-holding devices one on top of the other. Even when mounting a vice with a rotating base directly on the table I think it is good practice to remove the base unless it is needed for the operation.

Phil:)

oldtiffie
06-27-2009, 07:27 AM
I'd agree with that Phil - every time. But sometimes compromises have to be made.

oldtiffie
06-27-2009, 07:35 AM
Is that a vise I saw bolted to the rotary table ?

I had never thought to do that for the small parts that just need an arc or something. Thanks for posting that picture !

Lenord

OK lenord, back at it.

A rotary table is either a very versatile tool or can have many of its functions either performed by or in conjunction with other tools/accessories.

These tool-makers vises on the rotab or on a tilting plate will do fine for a lot of angular settings:
http://i200.photobucket.com/albums/aa294/oldtiffie/Vise/Vise2.jpg

Or even using (with care) this "crappy" old "Record" vice to hold stuff down dead tight against the base and jaws of the vice:
http://i200.photobucket.com/albums/aa294/oldtiffie/Vise/Vyce_clamp4.jpg

with this much "gap":
http://i200.photobucket.com/albums/aa294/oldtiffie/Vise/Vyce_clamp6.jpg

which might save me tying myself in knots with compound angles with this vise (which is excellent now but took a LOT of "getting right" - for light work:
http://i200.photobucket.com/albums/aa294/oldtiffie/Vise/Vise9.jpg

Rotab on my 3-in-1 lathe:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith09.jpg

Put one of these cheap and rough but but surprisingly accurate Chinese "X"-"Y" tables with integral vice on a rotab and the set-up is very versatile (vise is a bit "loose" but can be "corrected" with a rule or straight-edge - see previous):
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith06.jpg

I also have one of these very good Chinese "X"-"Y" tables that I can put an angle-plate and/or a rotary table on for use in measuring stuff under a microscope (yet to be got):
https://www.machineryhouse.com.au/Products?stockCode=M207

Here is a rotary table on a tilting angle-plate (it can be reversed and is just as effective):
http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_15.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_16.jpg

A vise on a tilting angle-plate:
http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_23.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_24.jpg

With a good straight edge or end on a vise and a good vernier or digital (preferred) protractor that is accurate to 0.1 degree = 6 minutes = atan = 0.0017 = 0.0017" per inch accuracy a rotary table may not be needed at all:
http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_20.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_21.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_19.jpg

Too many people are inclined to think of a rotary table as having to have a chuck on it or only work "on the flat" with only "X" and "Y" ordinates. Not necessarily so as some other wise very difficult compound angles can be set and used. Some can be achieved with a rotary table at all.

Some tend to think that "angular" surfaces and holes can only be done by tilting (left-right) or "nodding" forward-back) the milling head in the "X" and "Y" planes respectively - not so either.

I pretty well dislike having to tilt the head on my HF-45 mill as the head is awkward to move and manage and to set accurately - particularly 30 degrees and more past vertical or "centre". I will never use it in its horizontal position. I might if I had a good worm-wheel drive to adjust the tilt. My "Sieg" X3 square column mill has no tilt adjustment - which suits me - as it was very accurately trammed at the factory - which suit me too.
http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Seig_X3_mill/SeigX3_14.jpg

If I really must use a tilting head I will use the really good one on the milling head (with a worm adjustment) on n
my 3-in-1 lathe:
http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/AirSmith10.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_misc/Lathe1.jpg

For a real lift in versatility, I'd suggest making of these universal holders - mvgyver's top job here:

http://i200.photobucket.com/albums/aa294/oldtiffie/mockofunivestalswivel1.jpg

To really top it off - get a good "Spindexer" and use it with a rotary table or a tilting table or a protractor:
http://i200.photobucket.com/albums/aa294/oldtiffie/ER-32_C5/ER32-C5-8.jpg

Boucher
06-27-2009, 11:45 AM
Thanks for this excellent post! My brain is in overload. This opened up so many concepts that I had never thought of. It will take a while to digest.

Roy Andrews
06-27-2009, 12:37 PM
i have a 12" and an 18" troyke. the 12" gets used a lot and i usually put a plate on it if i need something bigger. after 3 jobs in a row where i needed the bigger table i got another high paying job that required a big table and i had another job that required the small one. so i decided to buy the 18" table. it's never been used since. buying that table has virtually guaranteed me that i will never get another job requiring that size table. the 12" i can pick up most days the 18" is close to 400# and sits on the floor wrapped in oily rags waiting for its day to go back on the K&T because thats the only mill i feel comfortable putting it on. i got both tables cheap the 12" ($30)because it was beat up and the 18"($150) nobody wants. i would look for a good used 12". its kinda big but that keeps the price down. when the time comes and i can't lift it anymore i will build a small jib to put it on the mill and still be money ahead. another point get a horizontal/vertical if you can find it. my 12" is horizontal only and i have to attach it to a angle plate to use in vertically.

lenord
06-27-2009, 07:09 PM
Thank you so much for posting the pictures. It gives me all kinds of ideas now.

Lenord

oldtiffie
06-27-2009, 08:35 PM
Glad to help.

As I understand it, that's what this forum is (supposed to be) all about helping each other in (mainly??!!)HSM/machining matters/topics.

A lot of people helped gladly me along over over many years - I am just carrying their example on.