The heart of this project is of course the wheel, which is a Grizzly 10" replacement wheel from their 2 x 72" belt grinder. It's very reasonable at $76 US, but has a small problem. It's meant to be secured directly to the prime mover. In other words it doesn't come with bearings and there are no machined provision for bearings. This puppy was meant to be locked on to the shaft of the motor that turns it.
I discussed this with my machinist friend and the prospects of machining places for a sealed bearings was going to be a little on the expensive side. Something about chucking it from the outside. Well, machine shops are not cheap and a lathe I do not have.
The trick will be to press a shaft in and build up some suitable bearings for the wheel spin freely on. Once again, Alaskabearhawk shows how he did it. Some 3/4" shaft and some pillow blocks inspired me build something that plugs into the BG-272, with only a few hours of tinkering.
A trip to the Metal Supermarket was fruitful. The sell 0.75" D.O.M. (Drawn Over Mandrel) tubing with 0.125" wall which should make a suitable shaft. A piece of 3/4" 4130 aircraft tubing would also work, but I couldn't locate that as easily as D.O.M. tubing.
Two 3/4" pillow blocks will keep everything rolling along. If you are curious, these bearings are inexpensive, like under $10 each, have a Zerk grease fitting and can handle a radial load of 2000 lbs. and an axial load of 1100 lbs. In other words, way overkill for this application, but over engineering is good right?
This is the 10" contact wheel from Grizzly. Part number G9242
A steel plate (4" x 5" x 1/4") and two 3/4" pillow blocks. I rounded the corners on the plate and took any sharp edges off.
This is the 3/4" D.O.M. tube. I shined this a wee bit with sandpaper. I pressed one end of this tubing into the hole in the wheel. It is interference fit, so takes a bit of force. I used a hydraulic shop press for this step.
Good old 1-1/2" H.S.S. square. The heavy wall (3/16") will give some solid support for the wheel. I bought 18" at Metal Supermarkets when I bought the D.O.M tube. Turns out that 18" is perfect for my machine. You'll have to size up to fit your grinder.
I used a tubing cutter to get this started nice and true.
The locking collar has to go on before the next spacer and bearing go on.
Note: I used carriage bolts in case that nice smooth look was required. Use whatever you like for bolts.
Bill of Materials
It would be great to hear from you if you make your own contact wheel.