July 9, 2023
Description
This is a work in progress. This is the first time I am trying this design, no long term use information exists. It may not be viable over the long term. Use at your own risk.
Two versions of a wire antenna corner pulley are provided. Both have about a 3", or 75mm, hub and were designed for use with 14awg THHN wire. These pulleys are not intended for typical load bearing applications, and are just for use with suspended antenna wire.
The two versions are fixed frame and split frame. Besides threading wire through the pulley, the axle of the fixed frame pulley can be removed & replaced to add an already strung wire. The split frame pulley allows the axle to remain in place while the frame swings open when the locking screw is removed. Both pulleys were designed to be attached to a cord for suspension.
Both pulleys are designed for assembly using M4 screws without nuts with the screw self tapping the far end component. Both pulleys' hub is designed to accept a 608 style bearing, using a center spacer for use of an M4 screw as the axle (20 - 24mm). The split frame lock screw should be 16-20mm. The lock screw may be considered optional as the suspension cord attachment will likely secure the frame parts in the correct orientation. Stainless steel hardware is recommended.
Printing should be done with a weatherproof, UV proof filament. A high wall and top/bottom layer count is recommended. I used 9 for my prints. No supports are needed.
After printing, smooth or shave any imperfections that might interfere with easy rotation.
Alternative frame versions include a 3mm recess on the axle screw entry to allow use of a 20mm cap head screw.
7/8/2023 - replaced split pulley files, a minor change reducing material used. Also added F360 & STEP files. Currently printing these in ASA.
A 4 inch version can be found here:
https://www.printables.com/model/523547-wire-antenna-corner-pulley-4-inch
License:
Creative Commons — Attribution — Noncommercial
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