(also posted to Yahoo tormekusers group, apologies to those who read both...)
Hello! New Tormek user (and I mean new as of about an hour ago) and I
have a question about flattening the back of a chisel prior to sharpening.
I got the machine setup, filled her up with water, etc. and started to
flatten. I tried to be careful to lay the back down near the edge of
the stone then tilt it in to flat, so as to not catch the edge. As it
went, I started to see why I had trouble with these chisels - I'd
apparently rounded the back of the edge pretty well in my first
attempts to sharpen them on sandpaper. So, anyway, I'm grinding away,
checking my progress every so often, and seeing a nice shine coming
through, but not near the edge, which is obviously not coming in
contact with the stone.
Looking through the handbook, I notice it recommends grading the stone
to 1000 afte flattening the back, and lapping it at that grit. Which
made me think, "Was I supposed to grade it to 220 first? and how much
more quickly would that make this flattening job go?"
So, should I grade the side of the stone for flattening? If so, will I
eventually need to true the side, too?
Also, what would a typical amount of time to flatten a chisel back be?
It felt like I could go forever.
I did MOSTLY flatten the back of a 1/4 chisel from the same set, then
ran it through the sharpening and honing procedure, and got a pretty
good edge. The back was still a bit rounded, so I had to chase the
burr a little aggressively, but I ended up with a shave-able edge. Not
a Wilkinson comfortable shave, but it cut hair.
Maybe I should buy new chisels and start over....
I have always used the inside of the stone for fast cutting and the outside for fine. From the factory, the inside is coarse and the outside has been cut, similar to the surface achieved by the stone grader. You can use the stone grader (smooth side) on the outside to maintain this fine surface.
Unless you do a great deal of flattening, you should not need to worry about reshaping the flat surfaces.
Good tip. Thanks!