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dlsinak
11-06-2010, 07:07 PM
I was poking around on youtube and found these two videos on a shop made belt grinder.

http://www.youtube.com/watch?v=lRUCHNZMwuQ&feature=related

http://www.youtube.com/watch?v=9OcbUTK5i5g&feature=related

It looks to be not so difficult to build. Where to get the contact wheels and the such?

It looks like the smaller wheels are rubber coated and one looks to be machined from aluminum or steel.

I figure if I could find a source for the wheels, I could make an excellent addition to the the home shop.

Anyone built one of these?

Pherdie
11-06-2010, 08:30 PM
Use the board search function. You'll find quite a bit of related information...

KMG used to offer the full unit or individual components.

Fred

darryl
11-06-2010, 08:31 PM
No, have not built one, but I did experiment with rubber coating. Seemed to work pretty well. I turned an aluminum tube to true it up, then used some very coarse sandpaper to rough it up good. Coated it with Plasti-Dip, which seems like some kind of vinyl/rubber compound. After it cured I ground the outside with the toolpost grinder, then coated it again to make it thicker. After the final grind it has an accurate OD and some reasonable gripping power. I have not tried Goop, although I expect it to work as well, and probably provide more grip than the Plasti-Dip. Other choices I am considering are epoxy silicone rubber and two part urethane, with choice of durometer. I think the epoxy silicone will let go and probably fly off with high rpm, but the urethane will probably stay put. I don't think it will offer any advantage over Goop, though.

I have two applications- one is a hand held 6 inch wide belt sander, and the other is a foot wide stationary belt sander. I can scavenge belts from our 36 inch thickness sander, which have become damaged at the edges. With luck I can get two 12 inch belts from those, and supposedly I can order belts made to the one foot width. Those are a bit long for a hand held unit, so I'm hoping to find some 24 or 36 inch long belts to use, at the six inch wide size.

Up until yesterday, I would have started with the 12 inch wide machine, since I have some belts for it and do have a need for the machine in my home shop. During some of my sanding the other day at work, I was wishing that the machine I was using had a wider belt and a different platen. Now I have that idea in mind, and I may start with that. In any event, I'll be making my own rollers, so we'll see how that turns out.

Your Old Dog
11-06-2010, 08:58 PM
I built one. My 3" drive and idler wheels are made from UHMW with bearings pressed into the ends. They work fine. My large 8" grinding wheel is made from an 8" caster purchased at Tractor Service Supply. Since then I've purchased a 8" steel caster wheel from Harbor Freight. I plan to epoxy 1/4" thick leather to the face of it but have not done it yet. My original 8" wheel is still plastic faced but it does present a slight bump from the belt seam each time it comes around.

If I were you I'd just go ahead and make it with either glued up plywood 3" wheels or UHMW if you can locate it.

I think if you don't have a lathe you'll wish you had one to make one of these. The wheels really should be trued up for nice running machine.

You are right in that a Belt 'Grinder is a tremendous advantage to a small shop as it really gnaws down metal :D

.http://inlinethumb61.webshots.com/34236/2514918900102651310S500x500Q85.jpg (http://entertainment.webshots.com/photo/2514918900102651310lcVoTT)

This particular setup allows me to use either 48 or 72" belts as the tracking wheel can be raised up the height of the tallest piece you see.

brian Rupnow
11-06-2010, 09:28 PM
I built mine years ago for smoothing the edges on flame cut plate brackets for building hotrods. Its one of my most used tool still today. I turned the two main pulleys from 4" dia. steel with bearings pressed in, but that is dramatic overkill. You do not need a rubber coating, just some means of adjusting the center to center distance of the two pulleys to put tension on the belt. UHMW would be a good choice and probably glued up wooden stock would work as well. A couple of good tips though.--#1-provide a method of tilting the axis on the non driven pulley to "train" the sanding belt--they all differ slightly, and every time you put a new belt on they will try to run off the pulley to one side or the other. #2--If at all possible, mount the drive pulley directly to the output shaft of the motor, or on a shaft in pillow block bearings with a direct Lovejoy type coupling. Using a V-belt drive sucks up a tremendous amount of the motors power. I have a two horsepower motor on mine, and although it works wonderfully, all the lights in Barrie go dim for 15 seconds when I turn the darn thing on.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/BIGBELTSANDER003-1.jpg

Ken_Shea
11-06-2010, 09:32 PM
If you have a CAD program I have modeled the KMG.
You do not need a CAD model but it helps pull things together with regards to what goes where.

The components that are not modeled are not because not sure on the exact type.

Can send it in most of the common formats if any one is interested, PM me.



http://i187.photobucket.com/albums/x175/Ken_Shea/ASSEMBLY.jpg