Building a Yagi with a 3D Printer, Continued

After my first tries at putting together a Yagi on a round boom in the field, I found out how awkward it is. The directors rotate every which way, and clamping them with bolts doesn’t help at all. The mount would hold better if I drilled holes in the boom for the mounting bolts. But that makes the build harder (you need to print a jig to drill accurately) and weakens the boom.

So I went with a square tube for the boom and redesigned the director mounts. At first it was a simple version, like in the photo below, but after a few weeks of use I gave up on it. It turned out I had left too little allowance for the plastic shrinking. I also wanted one universal holder for the whole antenna.

So I modeled the next version of the holder, the eighth one, I think. Now it takes a split driven element, and the tubes can be screwed to the cable. This version is for 10 mm tubes and a 15x15 mm boom.

The same holder also works as is for mounting the directors and reflectors on the boom. If needed, an M3 nut goes into the slot, and a bolt clamps the holder to the boom. For a portable setup, friction alone is enough to hold the elements in place without the clamping bolts.

One holder takes 9 meters of 1.75 mm filament, and the finished part weighs 23 grams.