The Burr

[Claus]

I’m engaged in the on-going process of learning how to sharpen my hand tools. I’ve gotten pretty good at various plane blades and I’m moving on to drawknives, inshave, and eventually to my travisher.

Most instructions tell me to work the edge until I feel the burr, or wire edge, on the backside. I get there consistently on my plane blades but I’m not raising a burr on the drawknives. And they’re not cutting as well as I think they should.

So even though the drawknife “feels” pretty sharp, if I don’t raise a burr does that mean not sharpened enough? If I don’t raise a burr after considerable effort should I go to a lower grit until I do?

Advice and comments appreciated.

 

[pop-pop]

Rather than a burr, I found that a small back bevel improves the feel of a drawknife. YMMV

 

[Mike Davis]

Technically, yes. To achieve sharpness the metal should be pushed off the bevel. This is how you know there is no flat or rough spots between the two planes. If you are honing with too fine a grit that takes extreme patience. Using a coarser grit to establish the initial edge is more efficient but takes care to avoid rounding or breaking that burr.

A back bevel can help in controlling the draw knife by breaking the curl and easing out of the cut more easily. Super sharp edge is even easier to control for me. Different people have different opinions about how much bevel is beneficial.

I think you should try a coarse stone and see if you can bring up the burr.

A draw knife is similar to the edge of an ax. A convex edge is stronger and will be easier to guide in and out of the cut.

 

[Claus]

Thanks Mike. Exactly what I was looking for. I’ll try some more grits. It’s that “extreme patience” thing that always seems to be my downfall. Super sharp is what I’m after- think “Curtis Buchanan carving a chair seat”. I have several clunkers to practice on and I really need to figure this out before I bring home any more orphans.

From my experience with hand planes it seems the best thing is to build familiarity with the tool. Use it, strop it, resharpen when necessary, repeat. That cycle over and over really seems to be the most productive for me.