Words and photos by Peter Geddes.
Most woodworkers will be familiar with the need to find support for the free end of a long board or panel that is held in the front vice. Often a stool, a box or the bin is used but is frequently not quite the right height. The adjustable ‘bench slave’ meets this need and will also support the free end of a drawer held in the end (tail) vice when being planed for final fitting.
My inspiration for the bench slave shown came from Scott Landis’s Workbench Book (Taunton Press). I used the sketch shown in the book but made a few changes. The type of wood used is not critical, although hardwood is preferable. I had a few suitable pieces of scented maple (Flindersia laevicarpa) left over from my new workbench! This tropical hardwood is similar to Queensland maple but harder, and very stable. It has a characteristic and not unpleasant scent, particularly noticeable when freshly worked.
The diagram and photos show the bench slave is straightforward to make. Careful work will ensure the mechanism works nicely if the slots are set out properly.
The base is made of two pieces measuring 300 x 75 x 45mm. The half lap joint is offset on one of the pieces so that the base is clear of your feet when being used. An offset of a third is sufficient and does not affect stability.
The leg is 750 x 45 x 35mm. If I were making it again, I would adjust the height so that it fitted neatly under the bench when not in use. When milling the leg piece make it longer than needed as the support block is the same size. The leg is tenoned with a 5mm shoulder and housed in a mortise in the base. Take care to align the mortise correctly with the base (the longest side of the mortise is parallel to the base part that has its half lap offset). The leg should be completed before the mortise and tenon is glued.
The slots in the leg are made by first drilling 10mm holes that are 15mm in from the edge, each 75mm apart and with the lowest 150mm up from the base. The dowel on the yoke drops into position most easily if the slot opening is fan shaped rather than parallel sided. In order to set the slots out, a temporary block (X) is clamped to the opposite side of the leg with its lower end referenced opposite the bottom of one of the holes. Using trial and error, two points (A and B) can be found on the block. These act as centre points for a compass to scribe the appropriate arcs. You’ll see in fig.1 how the lower arc A has the greater radius. The block can be clamped opposite each hole in turn to mark out the slot. Once done, the arcs can be cut out on the bandsaw and finished neatly with a file.
The support block is made from the surplus of the 45 x 35mm piece milled for the leg. The 10mm hole in the block is positioned midway along the block and 15mm in from the edge; in this position the block tucks in nicely against the leg whenever it is moved. The hole should be slightly enlarged with a round file so that the dowel moves freely in it.
The yoke consists of two wood plates each 110 x 25 x 5mm, and two short lengths of 10mm dowel. Drill accurate 10mm holes in the plates and round the ends on a disk sander. In order to ensure the yoke is square and out of wind it is best to clamp it in position over the leg while gluing it together. Avoid glue running down into the hole in the block. The dowel in the hole must be free to move. A piece of paper inserted between the yoke plate and the leg on both sides while gluing up will provide clearance.
The whole project is sanded with 320 grit paper followed by 400. Finally, three coats of Danish oil were applied. If you have worked accurately you will now have a handy support stand with an adjustment mechanism similar to the one I have that never fails to interest the people that visit my workshop.
Peter Geddes is a semi-retired veterinary surgeon and woodworker who lives in Brisbane also teaches woodwork.This story first appeared in issue 66 of Australian Wood Review magazine.