Thread: Charnley Forest hone lapping question

Sorry one more question...do I have to use oil on it with the chisel?

Poor DMT

I'm sure you could lap it with sandpaper at the back of the DMT. Personally I prefer sandpaper on a flat surface.

The chisel trick could work but I don't think you need to.

For a smooth finish you can lap it to 600 grit for a superbly smooth finish lap it to 1k or finer.

I disagree on that quite thoroughly. The chisel burnish is what will give you the smooth edge you want on a straight razor. This stone is novaculite, just like an Arkansas, and that step is an important one for smoothness of your razor edge. If you only want to use it for woodworking tools then it isn't really necessary.

The chisel will not scratch the stone as long as you keep the bevel aligned. I have a specific chisel set aside just for this that I put a convex bevel on to make it easier not to scratch the stone by getting out of alignment. I use oil exclusively on stones that are this hard - oil will let the stone do more cutting, where water will do more burnishing or polishing than cutting. The coticule lapping will be unnecessary - if you want to do it, do it before the chisel burnishing.

As far as lapping goes, the best (fastest) way to do it on a stone of this hardness is to use loose grit SiC for lapping on granite, glass or a cast iron lapping plate, but if you don't do a lot of lapping just go with the abrasive sheet.

Originally Posted by eKretz

I disagree on that quite thoroughly. The chisel burnish is what will give you the smooth edge you want on a straight razor. This stone is novaculite, just like an Arkansas, and that step is an important one for smoothness of your razor edge. If you only want to use it for woodworking tools then it isn't really necessary.

The chisel will not scratch the stone as long as you keep the bevel aligned. I have a specific chisel set aside just for this that I put a convex bevel on to make it easier not to scratch the stone by getting out of alignment. I use oil exclusively on stones that are this hard - oil will let the stone do more cutting, where water will do more burnishing or polishing than cutting. The coticule lapping will be unnecessary - if you want to do it, do it before the chisel burnishing.

As far as lapping goes, the best (fastest) way to do it on a stone of this hardness is to use loose grit SiC for lapping on granite, glass or a cast iron lapping plate, but if you don't do a lot of lapping just go with the abrasive sheet.

Just wondering is this method (the chisel lapping) works on all hard stones (chineese, jap. nats, coticules etc...)?

Yes it will work on all hard stones, but on Jnats for instance, the use of a nagura stone makes using a chisel redundant. Most Jnats will self-slurry if you try to chisel-burnish them anyway. It can be a useful technique but is best for very hard stones that do not shed much grit. It works well for the Cnat or PHIG from the feedback I got from a guy who I recommended to try it, probably wouldn't be much use on a coticule.

Thanks mate !

Let us know how it goes!