Thinning my F. Dick ProDynamic

(Raunchy pun omitted here)

The blade was way too thick behind the bevel and it showed with the bevel itself a mile wide, so I decided to cure that with my belt sander. Knocked off most of the shoulder first with a 220 grit belt at teh lowest possible angle, then ground down the bladefaces a bit, then rounded over the transition between bladeface and thinned part. Then went over it all again with a 400 grit belt and a cotton cloth buffing wheel with rough buffing compound. Not bad for a $150 sander. I finished with a new bevel (21° each side) on a cheaper waterstone and stropped a bit on my little balsa board loaded with medium buffing compound. Shaving sharpness achieved!

I have two of them (one still unaltered), so you can compare what the bevels of the knives looked like before and after in one pic:






high res: http://i237.photobucket.com/albums/ff200/mhpr53/HPIM0147_zps3a0so6rq.jpg

Right afterwards I used the knife to cut up some cauliflower and some thick stalks of leeks (which can stick and wedge terribly) and I was pretty impressed with the performance. Thinning makes a HUGE difference

Nice work. I thin a lot of F Dick and Forschner scimitars by belt. I start lower and finish higher. Did you use the platen or slack belt?

I used the plate for knocking the shoulder off and putting the same finish on the bladeface and the slack part for blending the transition between the two zones. It was pretty difficult because the slack part is only very short, not much longer than the blade is tall. I use this machine here:

http://ecx.images-amazon.com/images/I/41aDq9pxpYL.jpg

I may shorten the plate a bit for my next attempts so I have a longer slack part. The worst part is that almost no commercially available belt grinder has a plate and slack part that are fully accessible from both sides and from all angles - either the bolster or the handle will bump into some part of the motor housing or the tensioning mechanism when doing one side of the knife ...

I may also commission a little glass rectangle exactly the width of the belt I can glue on top of the plate, it is too broad and a bit uneven as it is. Still, one can't complain too much for around $150. Especially as it also runs my buffing wheel.


One problem I have that I find it hard to get a smooth convex cross section over enough of the height of the blade - only the lower maybe 2/3 of an inch are convex, from knocking the shoulder off and then blending the transition. How do you go about it?

I think you did well with what you have. I am not familiar with the Scheppach. Longer belt sanders will give you more slack options. I removed the platen on a smaller unit a few years ago and it was a reasonable fix. My most recent unit (106 cm) will be replaced this summer with a longer more powerful unit.