Thursday, May 30, 2013

Kaizen

When my kids were growing up, I often told them to work hard to do their very best and then be at peace with the result. Many of us struggle with that.  I know I do, especially in something like woodworking where my skills are developing and my standards always increasing.  If you are/were really good at  your profession, you get accustomed to performing at a very high level and when you go into the shop it's clear you aren't there yet.  You have to remind yourself that part of the fun of woodworking is that it's so challenging.  There is a reason that woodworking apprenticeships lasted seven years.

There's a second step though.  I've always liked the Japanese concept of kaizen, often called "continuous improvement" in large organizations here in the U.S..  It can be just another fad, another buzzword, or it can be a way of approaching excellence.  You can be at peace with the results of your woodworking efforts and still look at them critically to see how you can do better next time.  The idea is to make regular incremental improvements.  That's kaizen.  It helps me to take satisfaction from my work to think of any shortcomings as clues to how to improve. (It also helps to have a wife like mine who likes what I make and doesn't know/doesn't care about the flaws.)

My evaluation of the half-blind dovetailed drawers I've just finished making is an example.  It's hard to judge your own work objectively, but I'd say they are very good, not excellent.  It seems somewhat strange to me, but I think the main issue is marking out.  I use a mechanical pencil with 5 mm. lead and saw/pare to the waste edge of the line, but it just seems to introduce a little bit of error.  I just bought a better mechanical pencil designed for drafting to try, but I know many of the best woodworkers say that you just can't achieve a high level of accuracy with a pencil.  I've tried various marking knives but my problem is that I just can't see the lines I make even though I have good vision.  Marking out the pins from the tail board is a good example.  You have to hold the tail board absolutely solid with one hand while marking the pins with a knife in the other hand.  I never can see the result.  I know Lee Valley says to mark out the line with a pencil as a second step but when I do that the knife line is obliterated, so it's no help.  I need a way to make more distinct knife lines.  Marking knives often have handles that don't facilitate bearing down and I think that's part of the problem.

Paul Sellers uses an inexpensive Stanley knife that looks almost like a pocket knife with a small blade similar to this.  I've tried a small pocket knife and can produce a line I can see.  The issue with both is the bevel on both sides of the blade, but I suppose you get used to it and can compensate.  As I look at Paul using it, I think the big issue is the stout handle.  You can  really apply enough pressure to get a distinct line.   After I finish my current project, I am going to try this to see if I can produce distinct lines I can see clearly.  I have also thought of rehandling an Xacto knife.

As I expected, I also got a feel for what piston fit means in woodworking.  I went a little overboard and while the drawers work smoothly, it took a lot of fussing.  I notice that the best working drawer is the loosest one, so next time I am going to back off the fit a little.  It's just a matter of getting a feel for how tight to make them.

Installing the drawer bottoms with slips turned out to be a very good idea.  I can see why it was done traditionally in hand tool woodworking.  I'll definitely be doing it in the future.

4 comments:

  1. Andy, for marking out have you tried with a sharp non-mechanical pencil? I find it rides the sides of groove my knife marked out and becomes much easier to see without obscuring the knife lines. I've done it with a bunch of different knives without much trouble

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  2. After reading your blog, I thought about a citrus zester and the small thin curl it pulls from the skin of a lemon or lime. I imagined a cutting tool with a hook style point, that one would pull toward themselves (like a marking knife) on the surface of the wood. It would create a very thin groove which would be easy to see, but not too wide. I guess the cutting tip could be fabricated to cut a half “V” (flat on one side). I would think if it were designed correctly, a thin curl of wood would be generated similar to a zester (or curls of wood from a hand plane). Maybe not. Wood is not a citrus skin, is it? Just thinking.

    Dean

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  3. I saw/read this somewhere on the web where someone used blue tape as an aid. Unfortunately, I do not remember the site so I cannot give credit. The way I remember is that you place the tape on the end of the board you plan to cut pins in. Mark as usual with the knife. Peel away the tape from the waste sections and you should have a distinct visual line. For a single bevel knife with more heft, look at what Ron Hock offers (http://www.hocktools.com/Knives.htm)
    Hope this helps.
    -david j

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  4. I've also been concerned about the bevels on knives, so I got one that only has bevels on one side. Chris Schwartz calls them spear point knives, like this one:

    http://www.amazon.com/iGaging-Premium-Marking-Striking-Hardened/dp/B00B56B35Y

    I still have trouble with accuracy, but I think that has more to do with me than the knife.

    I've seen videos with people using a non-mechanical pencil to fill in the line, and then erasing lightly, so that only the graphite buried in the cut stays behind - resulting in a very thin line, that can still be seen. I've had minimal luck with keeping the graphite in the cut.

    Russ

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