Platen Adjustment Jig

[Bill Kirkley]

I needed to square the platen to the table on my belt grinder. I came up with the jig shown below as a way to first square the platen to the table, and second to adjust the platen to a predetermined proud distance from the wheels.

 

I have checked around and there does not seem to be a consensus as to how proud the platen should be. I chose 1/32 inch.

 

I made the jig by machining a 1/32 recess in a flat bar for the platen to sit in. In retrospect an easier way would have been to epoxy a piece of sheet metal 1/32 inch thick (21 gauge) to each end of a flat bar.

 

 

First clamp the jig to the platen with the platen bolts loose. Next you slide the platen until it contacts one of the wheels, and tighten the platen bolts.

 

 

Finally adjust the second wheel so it contacts the jig.

 

Edited March 19, 2016 by Bill Kirkley

[Andrew Hardesty]

Pretty cool. Sometimes it's more fun to mill a pocket than to epoxy a shim. How'd you radius the end or your support arms?

[Joshua States]

Andrew, If I'm not mistaken, that is the Wuertz Machine Works TW-90 belt grinder, and the bars come that way.

http://www.traviswuertz.com/?product=tw-90-knife-grinder

 

That's a nice idea Bill. I did something similar with my KMG. I also remove the platen and use the slack belt from time to time so I took a method for fast platen reinstallation from MS Steve Culver. I glued two small pieces of angle iron (JB Weld) in place to act as stops for the platen mounting bars. (Steve actually tapped and bolted his in place)

 

The upper bolt is moved away from the stop for clarity.

 

If I remove the platen for slack belt work, I can just slide it back it up against the stops and be right where I want.

Edited March 23, 2016 by Joshua States

[Andrew Hardesty]

Ahh. Ok, thanks.

[Bill Kirkley]

Thanks guys. Steve has a great site. There are a lot of cool ideas there. I took a bladesmith class from him at the New England School of Metal Works. Steve is an excellent teacher.

The grinder is a TW-90. There were a number of different grinders at the school, and most agreed that the TW-90 is tops. After using it I have to agree.