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Re: Sextant mirror foil mirror replacement
From: Peter Monta
Date: 2025 Jan 22, 09:11 -0800
From: Peter Monta
Date: 2025 Jan 22, 09:11 -0800
Hi Craig,
The foil would most likely not be flat enough, even though it's affixed to a flat support. I'd suggest using a small, thin (maybe 1 mm?), good-quality first-surface mirror epoxied on to the existing one. You may have to make the new mirror very slightly larger to address any vignetting caused by the mirror's being further away from the center of rotation. Keeping the mirror perpendicular to the sextant plane might be challenging.
Another option is to live with it. Provided there's some mirror still left, all you're really losing is a bit of light, and especially during daylight, that won't hurt much.
Cheers,
Peter