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Alistair Hosie
11-09-2007, 01:50 PM
I was too late to increase my bid on this really want one of these does anyone know where I can buy one or are they difficult to make.


http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=250183134089&ssPageName=STRK:MEWA:IT&ih=015

Spin Doctor
11-09-2007, 02:01 PM
I wouldn't think they would be too dificult. Just make sure the bars are parallel to one another and they are dead level. Another option might be a balancer that uses 2 discs at each end for the shaft to rest on.

small.planes
11-09-2007, 02:18 PM
I might be wrong, but it looks like theres bugger all that couldnt be made in a workshop one evening. you need a precision level to set it up, and a mandrel for the wheels.
The 'rails' need to be level so the wheel can roll to its heaviest spot, but thats about it. the rest is upto personal preference as long as theres clearance for the wheel

Dave

edit:
you could make a reasonable job using 4 bearings mounted so the mandrel can sit in the 'v' formed between them, no need to level the whole device then.

dp
11-09-2007, 02:32 PM
I was visiting a home-made gas turbine site one day and saw a clever way to balance the main turbine. Use a good piece of drill rod as an axle, no burs on the ends, and several inches long. Diameter is smaller by half of the bore in the wheel you're balancing. On that you put a collar/sleeve/tubing (which could be the inner race of a small bearing). Again, loose fit. Everything needs to be able to move freely. Onto that race you put the wheel to be balanced, and you then put the length of drill rod on a granite surface plate so the wheel and race are over the edge and free to move.

Then you roll the drill rod back and forth. As you do so the heavy part of the wheel will move to the bottom. Now you remove material (from both faces of the wheel) and repeat. At the end, the wheel will show no tendency to rotate as there's no longer a heavy side.

Most of us probably have everything needed in the shop to do this.

Alistair Hosie
11-09-2007, 05:09 PM
Could someone explain exactly how these work ,as I have used them before and it was along long time ago and now I don't exactly remember the exact sequence of events. Alistair

John Stevenson
11-09-2007, 05:10 PM
Could someone explain exactly how these work ,as I have used them before and it was along long time ago and now I don't exactly remember the exact sequence of events. Alistair

Gravity.................



.

small.planes
11-09-2007, 05:13 PM
You missed:
Put wheel on arbour, place on rails.
THEN gravity ;)

Dave

Alistair Hosie
11-09-2007, 05:18 PM
yes but how do you get the wheel permanently balanced? also is this any good or is it no good ?Alistair


http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=200169314027&ssPageName=STRK:MEWA:IT&ih=010

Mcgyver
11-09-2007, 05:21 PM
Alistair,

i wrote this up a few years ago on how i used mine

http://bbs.homeshopmachinist.net/showthread.php?t=12741

at the begining is a link to a diy version. too bad you missed that ebay one

aboard_epsilon
11-09-2007, 05:38 PM
if you dont have grinding wheels with an adjustable weighted arbour in the middle of them ...its no use to you at all .

think ive heard that they are for grinding wheels larger than 10 inches mainly

that went very cheap ......you could of made on that one .

all the best.mark

BadDog
11-09-2007, 05:54 PM
I've made adjustable hubs for my old POS grider that now runs wire brushes. Wire brushes, particularly coarse knotted ones, are often horrendously out of ballance. So I made some shims like McGyver, only out of 1/8" strap stock with much heavier offset. I ballance them right on the spindle, and it makes a HUGE difference.

John Stevenson
11-09-2007, 07:25 PM
Alistair,
I'll dig mine out in the mornig and take a couple of pics if you don't laugh. It was cobbled together in about 1/2 hour as the previous one I had couldn't handle a 16" diameter wheel by 4" wide and I wanted to balance a cutter block for a pencil sharpener.

Here's half of it.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/hidden/rexel%20block2.jpg

And here's the whole block at 8" wide.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/hidden/rexel%20block1.jpg

You can see the balance holes in the rim.

They need to be well balanced as they run at 5,200 rpm.

.

peterg
11-09-2007, 08:07 PM
Oneway a Canadian co makes one for about $60 US. Oneway sells lathes and accessories for wood turners. All made in Canada and of excellent quality. Peter

lazlo
11-09-2007, 09:24 PM
John,

I'd certainly like to see your balancing jig.

Is it static (like the one Alistair was looking at) or roller-bearing based, like the Anderson Balancing Ways?

Thanks,

Robert

andy_b
11-09-2007, 11:52 PM
John,

I'd certainly like to see your balancing jig.

Is it static (like the one Alistair was looking at) or roller-bearing based, like the Anderson Balancing Ways?

Thanks,

Robert

the heck with the jig, i want to see the pencil he's sharpening!!!!!

andy b.

John Stevenson
11-10-2007, 06:38 AM
Andy,

This is a commercial German pencil sharpener, normally they have a sanding drum in place of the cutter drum I made.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/hidden/rexel%20block1.jpg

The pencils are hopper fed and drop down via the notched index wheel top centre. this spaces them out and the traveling belt takes them thru the machine, rolling them as they go thru.

The track they roll on tapers down and as they pass the drum / cutters that applies the feed and the curvature of the drum gives the angle of sharpening. So by the time they have rolled along the track it's put the taper on.
There is then an outfeed ramp that goes to packing.

Incedently they can also do hexagonal pencils with no problem as the hex is that small it treats it as a round pencil

These are very fast, they can do 24,000 per hour but usually run at about 14,000 to get quality.

The drum was made to sharpen some special wax based cosmetic pencils that melted if sharpened on the usual sanding drum but these had to be slowed down to about 7,000 per hour again because of quality issues.

.

Your Old Dog
11-10-2007, 10:28 AM
Andy,

This is a commercial German pencil sharpener, normally they have a sanding drum in place of the cutter drum I made.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/hidden/rexel%20block1.jpg

The pencils are hopper fed and drop down via the notched index wheel top centre. this spaces them out and the traveling belt takes them thru the machine, rolling them as they go thru.

The track they roll on tapers down and as they pass the drum / cutters that applies the feed and the curvature of the drum gives the angle of sharpening. So by the time they have rolled along the track it's put the taper on.
There is then an outfeed ramp that goes to packing.

Incedently they can also do hexagonal pencils with no problem as the hex is that small it treats it as a round pencil

These are very fast, they can do 24,000 per hour but usually run at about 14,000 to get quality.

The drum was made to sharpen some special wax based cosmetic pencils that melted if sharpened on the usual sanding drum but these had to be slowed down to about 7,000 per hour again because of quality issues.

.

Can we assume that these pencils don't have erasers on one end since the kids aren't sharp enough to figure out how to sharpen a pencil in the first place? :D I had to learn to sharpen my own pencils. Even with the advent of Affirmative Action programs we still had to sharpen our own pencil? :D

ammcoman2
11-10-2007, 10:53 AM
As PeterG mentioned the oneway system is reasonable in price and Lee Valley Tools sells it. http://www.leevalley.com/wood/page.aspx?c=2&p=49226&cat=1,43072

I have one and the kit balances two wheels. It includes a balancing jig, works very well and solved a problem for me. Highly recommended.

Geoff

A.K. Boomer
11-10-2007, 11:24 AM
Iv seen a unique way of balancing the ducted fan turbines for what powers my little electric plane, Adjustable magnets on both ends playing "tug of war" with a steel shaft in the middle that the plastic fan is on...

Reed
11-10-2007, 11:36 AM
I made this one for my Abrasive #1 1/2 surface grinder, it has 12" wheels. I also need a balancer for my motorcycle wheels. So, I made one that servered both purposes.

http://i237.photobucket.com/albums/ff3/rstreifthau/WheelBalAsmbSGW2-s.jpg

Notice the rods on the base, the upright slides to accomodate the width of the wheel, grinder or motorcycle.

http://i237.photobucket.com/albums/ff3/rstreifthau/WheelBalAsmbSGW3-s.jpg

and the motorcycle wheel

http://i237.photobucket.com/albums/ff3/rstreifthau/WheelBalMotorcyclewheel-s.jpg

- Reed
Raleigh, NC

John Stevenson
11-10-2007, 11:51 AM
Here's my jig.

Don't laugh as it was a work of nessesity and not a project :D
Took about 1/2 hour to cobble up.

Base on this was 20" x 9" in scrap 12mm plate. 4 uprights in 12mm studding / allthread tapped into the corners and supporting two pieces of 3/4" square bright steel.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/balance%20jig1.jpg

The ends of the squares were milled flat so the lock nuts had somewhere to bear.

In use , throw it on a bench and drop a level across the rails at each end and along each rail. adjust the nuts to get level in both planes and away you go.

I don't balance grinding wheels on it as none of mine are the adjustable type except for the Myford Cylindrical grinder and that hasn't seen light of day for about 4 years.

What I do use it for the most is ventilation fans, I often get these in totaled where they have either flown off or sucked a brick in.
They usually have 6 to 12 curved blades on a flat back with boss.
Problem is most of the fans are unmarked so it's a crap shoot in sourcing supplies.
I draw in out in CAD, just the back and one blade and on the back I put two or three slots in to define where each blade goes. The blade then has tabs to match. These are then laser cut, the blades bent round something about the same diameter as the damaged ones and tapped into the slots.

The slots are MiG welded from the back and stitch weld from the front.
When I balance these I do it the opposite way to normal. Normally you get the heavy bit to the bottom and drill to lighten. On fans I weld a bit extra to the top, lighter part and keep doing this until it stays at rest wherever you place it.

YOD, Yes they can sharpen with rubbers on.

[ EDIT] If you are stuck for room this can easily take to pieces and be flat packed.

.

Alistair Hosie
11-10-2007, 01:38 PM
looks well thought out to me John.I suppose the main thing is every time I change a wheel I get terrible vibration.I have new grinders that I would like to change to better wheels and I am always afraid to attempt it.One of my eight inch grinders a really nice makita comes with swivel weights but no matter how I alter them it still vibrates the best I can do is to reduce it then bolt the grinder down so as it doesn't move Alistair

pntrbl
11-11-2007, 01:27 AM
My grinder shares the same long bench with my lathe.

That grinder vibrates so bad you'd best not be running any finish cuts.

SP

Alistair Hosie
11-11-2007, 11:59 AM
S P it doesn't need to be like that. Once you and I master the art or science of balancing, we will get the true benefits we deserve from or grinding wheels and grinding machines.Alistair

lazlo
11-11-2007, 12:34 PM
I made this one for my Abrasive #1 1/2 surface grinder, it has 12" wheels. I also need a balancer for my motorcycle wheels. So, I made one that servered both purposes.

Reed, very nice! That's a copy of the Anderson Balancing Ways, which is an extremely flexible design.

Could you tell us a little about your bearing arrangement? Did you use precision bearings?

lazlo
11-11-2007, 12:34 PM
YOD, Yes they can sharpen with rubbers on.

John, you don't even want to know how that translates to American English... ;)

Nice job on the balancing jig!

Alistair Hosie
11-11-2007, 02:14 PM
please tell me what you think of this ??Alistair


http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=200169314027&ssPageName=STRK:MEWA:IT&ih=010

Reed
11-12-2007, 05:38 PM
Lazlo,

Correct and then more. I also had these pics to look at.

Gundgtrand?
http://i237.photobucket.com/albums/ff3/rstreifthau/WheellBalancerSun.jpg

Crown, this opened my eyes to the possibilities of the dual use. Grinder/motorcycle wheels.
http://i237.photobucket.com/albums/ff3/rstreifthau/WheelBalencerCrown1.jpg

AndersonBros.
http://i237.photobucket.com/albums/ff3/rstreifthau/WheelBalancerAndersonBros1.jpg

About the bearings, I compromised and used off the shelf sealed bearing (forget the size),
- popped the seals
- carefully removed the grease (solvent)
- carefully cut back the seal from the inner race
- dried the bearing and oiled with instrument oil (I had from a previous life)
- carefully reinstalled the seals

Machined so the bearings balls' CL is centered on the wheel's edge. I used soft jaws to ensure the best concentricity as possible on the final op.

When I use it, I slowly make several revolutions before its actual use.

no claims it matches the examples, but it certainly takes care of me. :-)

- Reed
Raleigh, NC

lazlo
11-12-2007, 07:25 PM
Lazlo,

Correct and then more. I also had these pics to look at.

Gundgtrand? Crown, AndersonBros.

...and Stuhr:

http://www.reliabletools.com/itemimages/NovemberV07/v17k.jpg

Nice job Reed -- that's on my looong Tuit list :)

Peter Sanders
11-12-2007, 10:52 PM
Hi


you could make a reasonable job using 4 bearings mounted so the mandrel can sit in the 'v' formed between them, no need to level the whole device then.

Not really, there would be too much friction :)