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   Neil G4DBN (g4dbn@mastodon.radio)'s status on Wednesday, 19-Jun-2024 11:47:10 JST Neil G4DBN

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   This is roughly how the arms are used, but with the dish inclined at 18.9 degrees to the vertical rather than pointing at the zenith. Dish is 230 x 250 mm, made from 3/4 inch aluminium plate. The heaxagonal pockets are milled out to save weight but retain stiffness. The dish surface is accurate to about 20 micrometres, with 4 micrometre ridges from the spiral machining using an 8mm ball-ended carbide mill at 11500 rpm and 2800 mm/min on my SYIL X5 CNC mill #hamradio

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     Neil G4DBN (g4dbn@mastodon.radio)'s status on Wednesday, 19-Jun-2024 11:47:12 JST Neil G4DBN

     First attempt at a carbon-fibre-filled PLA support arm (one of a pair) for the milled-from-plate offset parabolic 122/134/248 GHz mmWave antenna dish. The left end attaches either side of a block bolted to the threaded holes behind the dish. The face is inclined at 18.9 degrees so points at the horizon with the bottom edge horizontal. The four mounting holes at the right end bolt to the enclosure containing the radar chip, focus rail, control electronics and feedhorn. Bit of Voronoi for bling.