• Sunday, April 30th, 2017

plane iron camber

Revisiting this matter, there need be no confusion as long as you keep in mind that the amount of camber that belongs in a plane blade is a function of how the plane will be used, and particularly, the kind of shavings the plane will take. Without getting hung up on numerical absolutes, here are three reliable guidelines that I use, which I hope readers will find helpful.

I wrote about camber in 2009 but I think some of it bears restating, and there are a few things I would like to add.

For a smoothing plane blade: Make a very small camber to allow the plane to produce very thin shavings, perhaps .001″, that are thickest in the middle and feather out to nothing at barely less than the full width of the blade. This produces only imperceptible scallops on the wood surface. The finer the shavings you intend to take, the shallower the camber should be.

For a jack plane blade: Use more camber to take thicker shavings without producing stepped-edge “gutters.” Vary the camber according to how aggressively you want to remove wood with the plane. The camber also makes it easier to direct the cut to take down the high spots on the surface of the board.

For a jointer plane blade: Make a very small camber to make the plane capable of correcting an out-of-square edge by laterally shifting the plane without tilting it. Position the deeper part of the camber over the high side of the edge to bring it down, and thus incrementally work toward a square edge. The camber also creates a miniscule concavity across the width of the edge of the board, which ensures there is never any convexity there, which would produce an inferior joint.

So, there’s the essentials. Coming up, I’ll revisit the bevel-down/bevel-up issue (that I brought up in 2009) in a quantifiable but intuitive way, look at the effects of skewing the plane, present a thought on chipbreakers, and maybe another thing or two that popped into my head while I was in the shop but forgot to mention so far. Then, we’ll take a look at the Tormek SE-77 jig, which I’m liking a lot.

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4 Responses

  1. Hi Rob-

    I just did 3 things that have really bumped up my planing.

    First, I decided to concentrate on using my LN 62. I find that concentrating on using this plane, getting my body mechanics in tune with it, notches me up.

    Second, I put a nice, gently camber on my A-2 blades, using the Eclipse jig. It has made me more careful about the sharpening process and finger pressure. Secondary bevel of 30 degrees.

    Third, I put a 45 degree secondary bevel on one of my 62 blades (I have a lifetime supply — long story). This allows me to plane Sapele (my favorite furniture and box wood) without tearout. I’m sure it’s a combination of the angle, careful sharpening and cambering.

    It’s not that I dislike the LN #4 or any of my other general purpose planes, it’s just so much easier to task blades and sharpen them accordingly on a bevel up. The 62 is a wonderful bevel up.

    Just my 2 cents.

    Thanks for your efforts,

  2. 2

    Steve, You mean the 62 1/2, the low-angle jack, right? (Why does Veritas come up with these 1/2 numbers for planes?) Yea, I like it a lot too, for the same reasons you state. I’ll have more to say about camber that relates to such planes in the next post.

  3. Hi Rob-

    No, LN = Lie Nielsen. The LN 62 is a low angle B/U plane. I like the traditional planes made by Lie Nielsen. Too many doodads on Veritas.

    — Steve.

  4. 4

    Oops! Got it now. I have the Veritas 62 ½. Anyway, I agree, BU planes do have convenience and versatility in their favor.