beamcompas

Beam Compass

Tool For Making Repetitive Measurements, or For Marking Circles

OK, so it is not high-tech, and it has been done before, but here is my way of making a beam compass for metal & carpentry work.

Pictures on the right pretty much tell the story. I had several 14 inch lengths of 1/4 inch OD stainless steel rod available, along with square sections of 5/8 inch steel tube. After drilling a few holes and adding some bolts & nuts, this is the result.

This is the finished device. Scroll down to see how I built it.

Holes in the traveler are 1/4 inch on one side and filed out to fit a 7/16 nut on the other side. This allows the nut to pull up against the traverse rod to lock the pointers in place. Wing nuts pull the pointer bolts up to fix the traveler at specific positions.

Slots for C-rings were lathe-cut in each end of the traverse rod.

A pair of jam-nuts (two conventional nuts jammed tightly together) make up the rod clamp, with the wing-nut providing clamping pressure.

The head was cut off the bolts used for pointers. They were then chucked in a drill and ground to a point on an abrasive wheel.

The result is a 14 inch wide beam compass for either woodworking or metal work. The most time consuming part was hand-filing the 7/16 nut shaped hexagonal hole in one side of the travelers.

You could adjust the length of the traverse rod (the beam) to make this almost any length you might want. It could also be scaled up or down by using different dimension metal components.