simple belt grinder

[Matt Bower]

I'd like to put together a very simple 2x72 belt grinder using Beaumont Metal Works wheels. When I say "simple" I envision basically a drive wheel direct mounted to the shaft of the motor, an idler wheel, and a short platen. (Short enough to leave some space for slack belt work.) Very much like this belt sander by Rob Frink, but made of steel and probably oriented vertically, with a work rest: http://www.metalwebnews.com/howto/sander1/sander.html I can upgrade later if the spirit moves me.

 

I envision powering it with a 3/4HP 1750 RPM motor (because that's what I have).

 

My question is what two wheels to start with. What size drive wheel? 4" or 6"? And for the other, a 2"x2" idler, or the tracking/tensioning wheel? Or could I get away with a contact wheel? I e-mailed Beaumont these questions and they referred me to their website, which unfortunately doesn't answer my questions. (I had already looked at the website. That's how I knew that they make a 2x2 idler, a tracking/tensioning wheel, and 4" and 6" drive wheels!) Kind of disappointing.

Edited March 11, 2008 by Matt Bower

[cdent]

Hi Matt,

If you're setting it up 'grizzly' style, the top idler wheel might work best as one of Rob's tracking/tensioning wheels because it has a crown on it. You could use a contact wheel for the drive, but you might consider switching to a shaft and pulleys. If you use a belt and pulleys, you could get basic variable speed, but also if you move the motor away from the drive/contact wheel then it won't interfere with your hand or work piece.

 

The bore on those drive wheels may not fit your motor shaft, and the contact wheels as sold have bearings in them and are free wheeling. If you leave the grinder 'laying down', then I'd think you could set up two idler wheels on a platen the same way that the KMG does, just different drive and tracking back by the motor.

 

Best of luck with the build, Craig

[Ken Kelley]

Given a choice between two belt speeds go with the slower one...hence the 4" drive wheel would be a better choice for your design. If you want to go with a contact wheel I think Grizzly still sells a 10" model without bearings. Don't know the hole size right off hand. As Craig points out you don't want the motor to interfere with your work so that might be a problem to look at. Hard to grind just one side of a knife. I took another look at Rob's simple grinder and noticed that the tracking and belt tensioning is controlled by moving the motor around on the mount. Definitely a show stopper when it comes to changing belts quickly.

 

Before you commit yourself to this project go over to US Knife Maker's Supply and take at look at Tracy's no-weld grinder http://www.usaknifemaker.com/store/index.p...0f9992b80634620

 

I think you will be happier with your project if you spend a little more money now rather than later when you find out that your simple grinder is simply driving you crazy. Whatever you decide to do have fun with the project.

 

Ken

[Matt Bower]

Thanks for the thoughts, and the good advice. You may be right that it'd be worthwhile to spend a little more now. I've been down that road before.

 

But what's wrong with welding? I like welding!

[Ken Kelley]

What's wrong with welding?? Nuffin at all! I use my Milller Trailblazer 301g for everything except sewing on buttons. One of the options for Tracy's no-weld grinder is to weld it up after you get it dialed in. That should stiffen it up a bit, although I hear that the standard model is plenty sturdy. I built my KMG clone with bolts but I know guys who just welded theirs and did a wonderful job. Whatever toots your whistle.

 

K

[Mire Blades & Tools]

gas powered 3hp works good if you need it in the back woods with no electric and has the benifit of varible speed without the cost. i have one like your talking about but alas no camera.

[Matt Bower]

Well, today I received my drive and tracking/tension wheels from Rob. And as I was examining the tracking wheel I realized that the bore of the wheel didn't look concentric with the bearings; there seemed to be a good 1/16" offset. My initial read: the bearings sit in countersinks, and the countersinks aren't concentric with the bore. Which I thought was really weird, considering that Rob CNC machines these wheels: you'd think that after producing probably thousands of wheels like this one those sorts of problems would be pretty well ironed out.

 

So I shot off an e-mail to Rob about the "misalignment" between the bore and the countersinks, and he immediately wrote back and very politely explained that what I was seeing between the bearings was a spacer, not a bore machined directly into the wheel, and that I could move the spacer around with a pencil or whatever to line it up with the centers of the bearings. So I grabbed a pencil and, sure enough, I can.

 

It's been a long time since I felt this stupid.

Edited March 24, 2008 by Matt Bower

[Ken Kelley]

Matt,

 

Don't feel so bad because you've got company in the boat. I thought the same thing about one of Rob's 8" contact wheels I recently bought. Looked in the bore and saw that the bearing wasn't lined up and about had a kitten or two. I soon figured things out so I didn't immediately sqwack.

 

K

[Matt Bower]

I soon figured things out so I didn't immediately sqwack.

 

K

 

I wish I'd been that smart.

[Sam Salvati]

http://www.britishblades.com/forums/showthread.php?t=54305

 

 

CANNOT get much simpler.

[Matt Bower]

Thanks for that, Sam. It's just about what I' envisioning, and having that one to look at makes some things clearer in my mind.

 

I do think I can make mine even simpler, though.