Wood Puzzles

A while back Roy Underhill had a program on The WoodWright's Shop that detailed making some wooden puzzles. These are two of those puzzles, one from walnut and one from purpleheart. I have found a website that show making some generic burr puzzles, and am planing to make a small sled for use with a dado blade to make some of these puzzles, perhaps as gifts.

3-Bar Puzzle

This first puzzle consists of 3 square bars, approximately 1-3/4" on a side, that intersect at right angles. The material here is 8/4 walnut, left over from the legs of the walnut hall table. The interesting aspect of constructing this puzzle is that the cut away portions are multiples of 1/9th of the side dimension of the bars. Consequently, this is determined directly on the pieces being cut, and not by trying to accurately measure 7/36ths of an inch (1/9 x 7/4). This piece is finished with a light shellac coat.

Burr or Knot Puzzle

This knot puzzle is just 3 planes intersecting at right angles and is the simplest of the burr class of puzzles. The material is purpleheart, a tropical hardwood that is very dense with a tight, straight grain. The important part of constructing this puzzle was that the interior rectangles had to fit the exterior dimensions of the mating pieces. The areas to be removed were marked carefully, using the pieces themselves as a guide, the bulk of the material hogged out with a forstner bit on the drill press, and the remainder cut with a chisel, just like a through mortise. The two 'C' shaped pieces were opened with a dovetail saw. Paring with a chisel achieve the final fit. The Purpleheart has a fairly coarse, open grain, rather like oak, an tends to break easily along the grain, which posed a few problems. The Purpleheart is also a heavy, dense wood, also making the chiselling work a challenge. You can see a repaired break on the top of the right hand 'C' piece in the disassembled picture.