The voyage of two Canadian boatwrights as they build their first craft.
Tuesday, March 23, 2010
How to put a clamp on things
Clamps are an essential part of any boatwright's arsenal. They find countless uses around the shop and are downright indispensable when laying laps. However, it always seems like one needs just a few more than he/she has. The boatwright is then faced with a question: "How shall I obtain more?". There are two options: buy some or build some. Unfortunately, the former is usually quite a costly affair, as clamps run anywhere from $7-$25 apiece. When you need to place one every foot on a 14' boat, it puts quite a dent in the project funding. Because of this, many people (including us) turn to the latter approach. Some design very elaborate bandsawn clamps, but, in our experience, it is much easier (and faster) to use a simpler approach. Using the method outlined below, it is possible to turn out clamps for under $2.50 each.
Firstly, it is important to determine what depth of reach is required. As we will be using 6" lap material, our clamps must have a deep throat. A 12" piece of 2x2 fits the bill perfectly. For pads, we used 1/4" material for the front part of the clamps, and 3/4" for the backs (ensure that the difference between widths is at least the same width as the joint to be clamped--otherwise the clamps will skew, reducing holding power). For hardware, we recommend 4-6" carriage bolts and 3-wing poly handles (available from Lee Valley). The plastic handles provide much more leverage than a wing nut, not to mention a lot more comfort. The photographs below should make it easy to copy our method
All of the parts for one clamp cut out (mise en place, as the French would call it). The 5/16" hardware ensures sturdiness.
After drilling a hole in each of the clamp halves, thread the bolt through...
Et voila, un clamp!
Hope that this tutorial helps to clear up any confusion surrounding the creation of clamps (and keeps a few hundred $ out of the hands of those Jorgenson guys :)