Why 9-10 inch disc grinders don't have work rests in knife videos?

[LARRYZ10]

Can anyone tell me why the truly skilled knifemakers like S.R. Johnson and others don't have work rests or tables on their disc grinders. Do they get in the way for flat grinding or are they considered dangerous. I shape bolsters and profile scales after assembly but before final shaping of knife handles and I use the table to get a tru level ( on a 5 inch disc ) . I could never keep things perpendicular without a level rest. I must be missing something obvious. I am trying to find an excuse for a 9 inch disc ginder with a 1 hp motor. Also, Is a VFD really that important on a disc like it is on a belt grinder. Thanks for your opinions. Larry

 

[MadBug]

Larry,
Yes, and yes. These grinders are for knife blades, and you end up mostly using the middle of the disc where a work rest would be. Variable speed I believe is a must have. I use mine to reduce hand sanding time, so I'm usually using 400 grit, or haigher, and running at about 20% to 40% speed.

 

[Stacy E. Apelt - Bladesmith]

VS and Reverse are real plus on a 9" disc grinder. I find 3/4HP will work fine.

 

[sunshadow]

If I am flat grinding on a disc I use the lower 1/3 of the disc so the paper is moving away from me. Remember, the backside of the disc is going up and the top is coming at you

-Page

 

[argel55]

I move it from top to bottom to change scratch pattern to make sure I am getting them all out.

 

[richard j]

larry, i have 3 vids i took of a member learning how to grind a blade on my disc sander. keeping the blade in the proper positioin when grinding is important. the blade must be kept pointed to the center of the disc. going too far up or down from the center can mess up the grind by changing the angle.

send me an email and i'll send you the vids. rje196021@gmail.com gmail works best since they have a 20 mb upload limit and i have pictures to go along with the vids.