"My 2 x 72 Belt Grinder - 3HP
I designed it to be somewhat universal - Using a flat platten, having the big wheel out, little wheel out, etc...
The table is a dog-bone design built with ball bearings joined with a rod. The table can move any angle at any location, as well as moved to be used in the vertical position.
This unit has to live on my grinder bench and room is getting real tight, so I designed the unit to have a motor overhead (keeps grinding dust out of the motor) and uses a cross shaft to drive the pulley on the opposite side.
In response to a question about the tool rest:
No keys, just two ball bearing joined (welded) to a round rod - ie... dogbone. I believe I used 3/8" flatbar with holes drilled for the balls to engage. These need to be thick so as not to deflect; I reef-down on that capscrew fairly tight, as the hardened chrome balls can slip. I also put a fairly large chamber on each hole to help provide more surface area for grip.
I'll try and snap a couple detailed pics of the table. No keys, just two ball bearing joined (welded) to a round rod - ie... dogbone. I believe I used 3/8" flatbar with holes drilled for the balls to engage. These need to be thick so as not to deflect; I reef-down on that capscrew fairly tight, as the hardened chrome balls can slip. I also put a fairly large chamber on each hole to help provide more surface area for grip. But once tightened down, it really holds very well What's not evident from the design photos below is that the magenta colored piece that welds to the under side of the table actually has a ball welded into the hole and centered. Like I mentioned, I'll try to snap some detailed photos for ya a bit later. I snapped a couple screen shots of my table design - hope this helps some."
In response to a question about whether the driver and idler wheels are crowned, and asking about the speed:
"Both are crowned - As for speed, I think I designed it to run at the recommended speed for alum oxide belts (4200 sfpm???????) - can't remember.
I've been using it for about a year or so now and seems to work great.
I mainly use it for general purpose fab and works great - I build maybe one to two knifes a year, so having it at the proper speed is not much an issue for me."
"I see that I designed it for about 4800 sfpm, isn't that about the correct speed for AO? "
