View Full Version : My 2X72 Belt Grinder

Dave Bonde
02-17-2017, 10:02 PM
I received a lot of good information here at SMC as well as other sources online while researching belt grinders so I thought I would share a couple of pictures of my completed sander.

Lee Schierer
02-17-2017, 10:25 PM
Nice, hopefully some guards are going to be added.

Dave Bonde
02-17-2017, 10:36 PM

Lee Schierer
02-17-2017, 11:59 PM
It would probably be a really good idea. There are lots of places to get fingers, clothes, etc caught which would cause some pretty severe damage.

Dave Zellers
02-18-2017, 12:04 AM
Wow. It's two different machines.

I'd ask how much to make one for me but since I had to ask, I already know I can't afford it. :p

Man will that be useful.

Dave Bonde
02-18-2017, 1:11 AM
I have just over $300 in it Dave. I salvaged the motor out of an old treadmill and had the bottom base plate, tool arms (1.5X1.5 aluminum bar) and knobs so that saved me some money. The stand it is on was just a stand I set it on to take the pictures it will probably be on a rolling stand in my shop.

Robert Parent
02-19-2017, 10:05 AM
Very nice!


Bill Adamsen
02-19-2017, 12:03 PM
Beautiful execution. Love the use of the shock absorber.

Bruce Page
02-19-2017, 2:02 PM
Nicely done!

Brian Brightwell
03-13-2017, 4:40 PM
Cool, are those tread mill motors DC? what hp and rpm.
I am going to get one of these soon.

Dave Bonde
03-14-2017, 12:05 PM
Yes DC, the one I used is 2.75 hp and rpm is variable from 0 to 6000 (I think) I never run it wide open.

brad jansen
03-14-2017, 10:17 PM
Excellent work! Great finished product and kudos for keeping a good budget on it.

Bet you can't make just one.

James Combs
03-27-2017, 4:34 PM
Dave, what did you use for the motor speed control?

Dave Bonde
04-05-2017, 11:04 PM
I used the parts out of the treadmill, bought a potentiometer and made the box. I had to rewire the board to make it control the motor.

Patrick Walls
04-17-2017, 8:53 PM
Dave, what did you use for the motor speed control?

Sorry to butt in but if you go to Ebay and type black box controller for treadmill motor one will come up. I think they are around $100.00 or $150.00 for a complete controller. KB electronics also makes a DC motor speed controller and depending on where you locate it they start around 180.00 or so. The thing with a treadmill motor is you have to keep the fly wheel on it or you will loose a lot of torque.

Mark Baldwin III
04-25-2017, 9:22 PM
Very nice. And the flat platen attachment is quite nice as well. One lesson I learned on mine is that the aluminum tooling arm will gall with the aluminum "box". I added a thin layer of plastic to each side. I set mine up to a fairly close fit, if you have a looser fit, it may not be a problem.
Once you have a 2x72, you will wonder how you ever lived without one.

Doug Walls
05-15-2017, 1:20 PM
Nicely built belt grinder.:)

I hope to build one this summer, I'm sure it won't be as nice as yours with all that aluminum & the DC motor with controller.
Probably just regular steel & a simple step-pulley for speed adjustment.


george wilson
05-16-2017, 10:28 AM
I bought a 1 1/4 H.P. motor and speed controller from Surplus Sales for a pretty decent price. It works just fine. My belt grinder is a Wilton "Square Wheel",which is what most of you are emulating. My drive wheel is 10" in diameter. To my annoyance, that wheel ran with a wobble. I mounted it in the metal lathe and trued it up. Now it runs perfectly. I gave Wilton a piece of my mind,saying that I expected a $2000.00 grinder made in USA to run better than something made in china. Later I found out that the grinder was MADE IN TAIWAN!!! I don't think that Wilton makes ANYTHING in this country any more. They are just riding the name for the high prices they can get from it. Maybe they still make their expensive vises here,I don't know. I had a 12" disc,6" belt sander that was such a bother to track,I GAVE it away. The tracking mechanism was a HUGE PAIN!!! I had gotten it used,but in great shape otherwise. I bought a Delta "sanding Center",and it has a dust collector port which collects NO DUST when hooked up to the large,industrial 20 HP dust collector we have. I hate that silly miter gauge slot that runs right at 90 to the disc. I fitted a snug piece of wood into the slot. What a BOTHER!! Just there to sand circular discs.

When finishing an already ground knife it gives you a lot of confidence for those last few grinding passes over a very thin hollow grind,to be able to slow that belt way down. That way you know if you touch the blade to the belt a little wrong,you won't cut a big dollop out of it.

I wanted a curved platen under the belt to simulate a large diameter wheel,as used in the 18th and 19th.C's. To do that,I turned a block of steel about 2" x 4" and 3/4" thick until the curve on the surface had a very large radius. Welded on a simple bracket on the back with a screw in it to grasp the platen. The belt runs right over this block perfectly well. I can now achieve wide hollow ground areas on the knife,which are like those you see on antiques round with a 3' diameter wheel. They used huge wheels up to 6' in diameter to grind forged musket barrels. I have even seen octagonal rifle barrels ground on a huge wheel and just left that way. You can still see that the "flats" on the barrel are a bit hollow. They might have expected the gunsmith to draw file the ground hollow flats away,but this gunsmith used the barrel as purchased.

Carroll Courtney
06-09-2017, 1:09 PM
That is awesome which will be one of my first projects once I get couple of my machines going.Maybe another thread could be started by members who have made their own belt grinder.With some pics,maybe plans if used and list of the resources where parts were collected.George maybe you could get it started when time permits of yours.Heck I seen one on CL's other day and I'm sure its top of the line which price at 1300 used.I always watch "Forged in Fire" where they really use belt grinders.Applying lot of pressure on the belts-----Carroll