I needed a set of blocks to hold bicycle tubing in my vise. These blocks allow you to hold thin wall tubing securely without denting or marring them.
I chose to make 7 blocks. One longer block with three different tubing sizes and 6 blocks with one tubing size each. I chose sizes based on common bicycle tubing diameters.
I created blocks for holding these diameters of tubing:
1/2" or 12.7mm
5/8" or 15.9mm
3/4" or 19mm
7/8" or 22.2mm
1" or 25.4mm
1 1/8" or 28.6mm
1 1/4" or 31.8mm
1 3/8" or 34.9mm
1 1/2" or 38.1mm
Step 1: Materials
I chose to use a harder wood for durability. I used some maple scrap a friend had lying around. I started by planing/joining the wood in to a 3x3" plank. I then used a chop saw to cut the plank in to 6 3x3x3" cubes and one 3x4.5" rectangular piece.
Step 2: Drill the Holes
After I had 3x3x3" cubes and a 3x3x4.5" block I got ready to drill some holes. In order to keep the blocks as strong as possible it is best to drill the holes perpendicular to or through the grain. This will prevent the blocks from cracking when you clamp the tubing in them. I marked the center of each of the 6 cubes on the face grain. For the the rectangular chunk I marked the centerline and spaced three marks evenly across the piece. I used Forstner bits to drill clean, uniform holes.
After drilling holes I cut the blocks in half. I set the fence on the band saw to 1.5" (half the blocks width) from the blade and passed each block through. Cutting the blocks after you have drilled the holes has an added benefit. The kerf (or width of the blade) removes some material. This removed material makes it so the blacks will fit tight on the tubing. With a tube in the block the two wood sides of the block won't actually touch, the kerf should provide enough gap so the pressure is on the tubing, holding it firmly. Alternatively you could cut all your blocks in half first then clamp them together with some sort of spacer (like playing cards) before drilling them. If you don't have a ban saw and have to make your cuts with a wider kerfed blade it would probably be better to use the cut then drill method.
Step 4: Mark Your Blocks
To keep the blocks easy to identify I decide to label them. Because bicycle tubing is often referred to in many ways I decided to include fractional, decimal and metric measurements on my blocks. I used a laser cutter for clear, clean, permanent marks.
Now I gotta go file some tubing!