12-15-2015, 03:49 PM
(This post was last modified: 12-15-2015, 04:03 PM by stargazer.
Edit Reason: more info
)
I'm not experienced cleaning a sextant, but I have cleaned front surfaced (delicate) telescope mirrors, one worth $$$. I used distilled water, one drop of Dawn detergent in a gal of distilled. I first poured it over the mirror to wash away grit.
I then use more water and let soak a bit, then GENTLY wipe with the type of loose cotton you buy in a roll between papers in a drug store. Thoroughly rinse with distilled water. This is the generally accepted method.
I don't own a good sextant so I don't know what type of mirror. You want to avoid adding microscopic scratches to the surface. Normal water definitely will leave spots, minerals perhaps.
Since my telescope is worth more than my car I'm fussy about it. You decide about your instrument.
Here are some guys on youtube cleaning a smaller mirror out in the field, using the technique I use.
https://www.youtube.com/watch?v=py3CaZ0Y2JM
Edit: Just checked my cheap plastic Davis sextant and (naturally) it has rear surfaced mirrors, so the glass front is much harder than the reflective surface which is protected by the glass. Wouldn't need to be so fussy with it. For my "quality instrument" I might just rinse with rubbing alcohol and wipe with lens cleaning pads or microfiber.
I then use more water and let soak a bit, then GENTLY wipe with the type of loose cotton you buy in a roll between papers in a drug store. Thoroughly rinse with distilled water. This is the generally accepted method.
I don't own a good sextant so I don't know what type of mirror. You want to avoid adding microscopic scratches to the surface. Normal water definitely will leave spots, minerals perhaps.
Since my telescope is worth more than my car I'm fussy about it. You decide about your instrument.
Here are some guys on youtube cleaning a smaller mirror out in the field, using the technique I use.
https://www.youtube.com/watch?v=py3CaZ0Y2JM
Edit: Just checked my cheap plastic Davis sextant and (naturally) it has rear surfaced mirrors, so the glass front is much harder than the reflective surface which is protected by the glass. Wouldn't need to be so fussy with it. For my "quality instrument" I might just rinse with rubbing alcohol and wipe with lens cleaning pads or microfiber.