20 Jul 2010 federico   » (Master)

Tue 2010/Jul/20

  • A Roubo bench for woodworking

    Since I got interested in woodworking, I have used various inadequate surfaces to work and hold the wood. A wooden saw-horse that our builders left behind, the edge of the balcony, the quasi-vertical edge of the bathtub. This is all extremely uncomfortable, and so for the past months I have been working on a real woodworker's bench.

    Roubo workbench

    This is the back view of the bench, with a few bar clamps and a chisel holder.

    Back of the workbench

    André Roubo was a French cabinetmaker from the 18th century, who wrote a massive treatise on all the then-known techniques for working wood. The woodworking community online has been abuzz with a translation of Roubo's book that is being prepared by the editors of Popular Woodworking magazine.

    In his book, Roubo describes a workbench and its accessories in detail. This bench is a variation of that one.

    My bench is built from a thick slab of cedar on pine legs. The thick slab makes the bench heavy and stable — it is a royal pain in the ass to use hand planes on a bench that slides around the room. The legs are joined to the surface with through-dovetails and tenons. I am not exactly sure why Roubo built dovetails and tenons like that, but it has something to do with wood movement — you want the face of the legs to remain flush with the front face of the top, so that you can have a continuous surface for clamping.

    The legs have short stretchers with double-wedged tenons, and long stretchers with tusk tenons. This kind of joinery is done without glue; that way if any joint comes loose, I can just hammer it back into position.

    This is how the bench top is joined to the legs.

    Through-dovetails and tenons

    The main function of a workbench is to hold a piece of wood steady when you are working on its faces, edges, or ends. The bench needs to let you hold things in the X/Y/Z axes so that you can work on them.

    Here you can see the leg vise. You can use it to hold a board to work horizontally on its edge or vertically on its end. The leg vise is built using a commercial steel screw. The bottom rail keeps the vise vertically parallel to the leg. The holes in the rail are so that you can fit a metal peg on the outside of the leg, which acts as a fulcrum for the vise.

    Leg vise

    To hold the wood down and work on its face, you use holdfasts. A blacksmith made these for me. They have a 3/4" shaft, which you then fit through holes on the surface of the bench. To secure a holdfast, you just bang on the top of the curve with a mallet. To loosen it, you bang on the back of the curve. The holdfast gets "stuck" inside the hole where it fits, and that is what keeps it steady. The main advantage of holdfasts over clamps is that while you can only use clamps close to the edge of the bench, you can use a holdfast in any place that there is a hole.

    Holdfasts Holdfast in secured position

    Finally, there is a square block of wood which you can move up and down to use as a stop for planing the faces of boards. The stop keeps the wood from moving forward as you plane it. There is also a crochet, or hook, which you use to hold the end of long boards while planing their edge; the other end gets clamped in the leg vise.

    Crochet and planing stop

    People have been talking a lot about workbenches. This is the material that I used as reference:

    Bob Rozaieski's epic videos on building a workbench without using a workbench, using only hand tools:

    Chris Schwarz builds (yet another) workbench:

    Too many parts to list, but see 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,

    Roy Underhill makes sliding dovetails look easy:

    Parts 1, 2

Syndicated 2010-07-20 11:40:00 from Federico Mena-Quintero - Activity Log

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