EcrosTechWiki | Woodworking / Sharpening Woodworking Tools

Sharpening Wood Chisels

TO DO. Generally easy. Primary bevel on bench grinder to 25°, hollow, then flatten on fine side of diamond water stone. Secondary bevel at 30° on extra-fine side of diamond water stone. Hone with green compound on suede leather. Strop with bare leather. Only problem is that the honing jig I got from Rockler only fits my English chisel, the others are too thick at the shoulders.

My Skew Chisel, which I made from an old file

Sharpening Lathe Tools

I only have a couple of lathe tools, but everyone tells me that I need to keep them sharp.

Sharpening my Home-Made Skew Chisel

Brian Havens devotes this video to a discussion of how to grind a skew chisel. He talks about the included angle of the point, the angle that the cutting edge makes to the axis of the tool and the shape of the cutting edge, i.e. how curved it should be. He not only describes the advantages and disadvantages of each choice, he demonstrates them on the lathe while he's talking! He has a multitude of lathe tools so he can grind up all the useful combinations he likes. After viewing his video, the single choice that seems sensible to me is a 40° included angle (so each face is ground at 20°), a 70° angle of the edge to the tool axis and a straight edge (for ease of sharpening). Allan Batty also "work[s] with a grinding angle of about forty degrees".

TO DO. Not much more difficult than wood chisels. Bench grinder to a 20° bevel half-angle, hollow, on each side, holding at 20° from vertical. Flatten on fine side of diamond water stone using a custom made jig. Continue with extra-fine side at same bevel angle. Hone with green compound on suede leather. Strop with bare leather.

Sharpening the Crown Skewchigouge

Figuring out how to do this was so difficult that I have an entire page devoted to the subject.

Sharpening Turning Tools in General

I don't intend to make a big thing out of turning, so I've no plans to acquire other tools. Except, maybe, a parting tool, which I will figure out how to make for myself. It shouldn't be difficult to sharpen. However, while figuring out how to sharpen my skewchigouge I became aware of how difficult it is to codify the sharpening of things like spindle and bowl gouges. There are jigs for doing this at a bench grinder, but how to set up the jig for any given result isn't well understood. I've created a page on which I can discuss the Oneway Wolverine Vari-Grind jig with Ted Ross of Ted's Turnings. Interestingly, Oneway Manufacturing's claim for this jig is "... you can dramatically reduce the difficulty of producing these grinds", but they don't say that the jig makes anything actually easy! Here's a link to the page.

David Carter in this video shows the sharpening of a variety of lathe tools on a variable-speed bench grinder with 8-inch diameter wheels of 80 and 180 grit. The tools are a curved-edge skew (0:53), an 1/8" parting tool (2:13), a ¾" roughing gouge (2:43), a ½" spindle gouge (4:14), and a 5/8" bowl gouge (6:33). He says that the tools are ready-to-use off the grinder. As far as I can tell, he's using the coarser grit. He uses the Vari-Grind jig for the spindle and bowl gouges, but doesn't attempt to explain what this does and doesn't do for you.

Notes and Resources Related to Sharpening Woodworking Tools

3M Lapping Film Yellow (Woodcraft Item # 157225). "12 micron (#1200 grit) quickly removes steel ..."

3M Lapping Film Gray (Woodcraft Item # 157214). "... 5 micron (#2500 grit) refines and produces a keen edge."

3M Lapping Film Green (Woodcraft Item # 157227). "... use the 1 micron (#8000) prior to the 0.3 micron." The color is actually a very pale yellow / green.

3M Lapping Film White (Woodcraft Item # 157212). "0.3 micron (#18000 grit) leaves a mirror finish."

Green Honing Compound. "Most 'green' compound is comprised of chromium oxide at pretty small grit size (at least less than 1 micron, with many averaging ~0.5 micron)." I've not found more definitive information.