broom stick handle thread: 3/4” and 5 threads per inch
Apparently there are two standards common in the USA, both based on a 3/4” dowel (0.75 inch or 19mm). One standard (shown here) has a pitch of 5 threads per inch; the other has 4 threads per inch. However, there is a LOT of variation due to the manufacturing of wood, plastic, milled aluminum, and cast aluminum tools on the market.
ref https://www.thingiverse.com/thing:84774
I have two different broom stick handles (I think both came from home depot) and they are both 5 threads per inch. The diameter differs a bit, though, but these threads are usually pretty loose anyway, and 3D printers aren’t great at making precisely-sized holes, so not sure that’s real.
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