I copied something off the reflector here a few years back using piano wire, AKA music wire, which should be available from most hardware stores. Thinking it was Adrian, N6ZA, who sent me pic’s of what he had made. I purchased at a local Ace Hardware. I used a piece of carbon fiber for the boom. Weighs next to nothing and worked pretty well. Sourced it through Dragon Plate (dragonplate.com) ( but pricey $$) Haven’t used it for a long time now as I don’t do much VHF/UHF work unless it’s the ARRL gig. I think this was the design used: THE KD5IVP 2 Meter 3 Element Backpacker Yagi Antenna Project!
Some peeps use an arrow shaft for the boom. The carbon fiber I used is really small diameter but the wires slide into it nicely for storage. Strapped to back of pack. Fun project.
73, Todd KH2TJ