Sharpening Mortise Chisels

[Stephen Jackson]

I have recently acquired a used mortise chisel (my first), which requires some honing to bring it to the point where I am comfortable in using it. While I have been able to master the skill in sharpening a regular bevel-edged chisel, the mortise chisel worries me a little in that with it being deeper than it is wide, how easy is it to keep the back flat on the sharpening stone, without it "tipping", and consequently rounding the rear surface? Are there any special techniques or tips to use when sharpening this kind of chisel? As you can guess, I haven't tried to sharpen it yet.

[Don C Peterson]

For most of my mortise chisels, I use the same technique that I use for the bench chisels and have not had any problems. For really narrow ones though, I tend to use a forward and back motion rather than a side to side motion on the stones. This keeps the chisel from wanting to roll.

[Robert Rozaieski]

When you flatten the back, don't stroke the chisel side to side, rather move it along the long axis of the blade keeping firm downward pressure on the bevel as close to the edge as possible, not on the shaft of the chisel. Keeping the pressure as close to the back of the blade as possible (lower center of gravity) and moving it along it's long axis rather than across the long axis should prevent the chisel from rolling.

[Derek Cohen]

I hone my mortice chisels with a honing guide because they all receive a 35 degree microbevel on a primary bevel which is ground at 20 degrees.

These will give you an idea of what it looks like ...

http://i13.photobucket.com/albums/a262/Derek50/Chisels/RayIlesmorticechisel1.jpg

Regards from Perth

Derek

[Steve Hamlin]

I find the length of the primary bezel makes it relatively easy to register, and gives good feedback.

I intentionally soften the transition from the primary bezel to back/face, as this area ends up as a pivot point when I'm prying out the waste.

One thing I have had to correct before is a bezel which was out of square - since it is a bearing surface during prying, I found the edge was was getting thrown into the mortice side (of, course, this could also just be my rotten technique :) )

Cheers
Steve