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The Drawknife

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  • The Drawknife

    The drawknife is among the most useful and versatile tools in boatbuilding and general woodwork, but is also frightening, because it can behave like a power tool and get the beginner into a lot of trouble very quickly. Overcoming that trouble, however, is merely a matter of sharpening the tool and learning to read the grain of the wood.



    As my stones live their life out on the bench where they belong for daily use, they are filthy from saw and metal dust and need cleaning. A simple stiff parts-cleaning brush and a pan of kerosene does the trick. I’ll relube them generously with cutting oil as I use them.



    Then I simply mount my stones on a board extended from the Workmate so the drawknife’s handles have clearance, and clamp everything down firmly. The blade back is flattened first, using coarse and fine stones….the single most important phase of sharpening….do it thoroughly. Handle clearance is critical because sharpening is best done with both hands holding the blade….not holding the handles….and close to the stone for better feel.

    This drawknife is an ancient family piece from Granddad made by Braun in Schweig, Switzerland…the blade has about half its original depth, one tang has a silver braze repair and these are the third set of handles I am aware of. I suspect my Great-grandfather brought it with him when he immigrated. It’s the only one I own…or need, as it still works just dandy.



    The blade bevel is 20 degrees…we’ll hone that next and add another 5 degrees or so of secondary bevel.



    The primary bevel is honed on the coarse stone and secondary bevel on the fine stones. With a bevel this large, and with proper hand position as shown, it is simple to “feel” the bevel so as to not add rocker to the primary bevel.



    Then I strop both edges on the 8 inch buffing wheel with Knifemaker’s Green Rouge….you should use a leather strap anchored to the floor if you haven’t done a lot of freehand buffing, as catching an edge and throwing this piece downwards is an excellent route to arterial bleeding.

    Continued…

  • #2


    Now we do the second critical part…reading the work piece. Pushing a felt tip pen against the board firmly will cause ink to seep along the grain line where it is not obvious. On this plank of Red Alder I have marked the grain…you can see the grain runout that occurs even in a properly milled board around the knots….



    ….and where there was a knot nearby even though it isn’t evident in the board. I’ve also marked the only direction the drawknife will successfully cut.



    Moving to the shaving horse, it becomes obvious that the drawknife will cut cleanly with excellent control slicing in the direction of the grain….



    ….and will dig deep and gouge (below) when slicing in the wrong direction:



    But if this were a rough planking bevel on a strake you just spent an hour getting out, can we clean the gouge and recover? Sure….



    …we just switch to the direction dictated by the grain, regaining our precise control and can rough-cut clean, accurate bevels that only need a touch with a finely-set smoothing plane to make perfect.

    Handles up or handles down? Push or pull?

    All of the above. The angle of the blade’s attack doesn’t change when the tool is upside down, but cutting with the bevel down gives better control in taking thin shavings….and cutting with the bevel up is several fold as fast as using a plane to hog wood rapidly.

    If you look at a larger view below, the blade in my pics is slicing on a very slight bias…my left hand is an inch or so ahead of my right hand while pushing...and as the blade dulls, I'll increase that bias unconsciously as I work:



    It’s a mistake to think these tools are only suitable for tapering riven cedar shingles….a little practice pushing as well as pulling and you can rapidly trim with precision a piece too big to move into the shop….

    …once you master reading the grain of the wood.


    When we build, let us think that we build forever. Let it not be for present delight nor for present use alone. Let it be such work as our descendants will thank us for; and let us think...that a time is to come when those (heirlooms) will be held sacred because our hands have touched them, and that men will say, as they look upon the labor and wrought substance of them, ‘See! This our father did for us.’ “ --John Ruskin.

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