Restoring (resivering) sextant mirrors.

[Jungboy]

I have a Plath Navistar Professional I have owned since 1978. It has been stored for many years and the mirrors have become mottled and unclear. I have encountered difficulty buying replacement mirrors or having them reconditioned. Does anyone know of an outlet that can sell me new mirrors or recondition them? Perhaps someone knows a process to do it myself. Thank You in advance.

[SeanPatrick]

Welcome aboard!



Bill Morris has a blog post detailing how to do it yourself. But he also wrote:

Originally Posted by Bill Morris

However, for rectangular mirrors at least, it is much simpler to cut new mirrors from 4 mm modern float glass mirror stock. Float glass seems to be flat enough for the purpose, as exposed in the post "How flat are sextant mirrors?" I suspect that much mirror glass from scientific suppliers is just common float glass such as can be had at very little cost by speaking nicely to your local glazier.

[Epikur]

Sextant mirrors are surface mirrors, that is the actual mirror is on the surface of the glas not its back surface.

[Jim Cate]

Not sure, but IIRC there is a section in Bowdich about re-silvering. Not on board right now so can't check it for you.

Jim

[Wotname]

Welcome aboard CF Jungboy.

It would help if we knew where you are however here is one place in the USA and another in the UK.

https://www.robertwhite.com

https://bcookeandson.co.uk/services/...-refurbishment

[Wotname]

And if you are in Europe - https://shop.cassens-plath.de/en/blo...service-repair

[SeanPatrick]

Originally Posted by Epikur

Sextant mirrors are surface mirrors, that is the actual mirror is on the surface of the glas not its back surface.

Some are first surface mirrors, most are not.

[HankOnthewater]

I have the same problem as Jungboy, but have a different sextant (Saura). Once I asked a glazier. He was not interested and could not offer further advice.
Anyone knows a place in Oz for this kind of repair/replace?

Thank you SeanPatrick for post #2, as always, your contributions are very helpful.

[Wotname]

Originally Posted by HankOnthewater

I have the same problem as Jungboy, but have a different sextant (Saura). Once I asked a glazier. He was not interested and could not offer further advice.
Anyone knows a place in Oz for this kind of repair/replace?

Thank you SeanPatrick for post #2, as always, your contributions are very helpful.

While I doubt there are any 'sextant repairers*' in Australia anymore, if you remove the mirrors, it might be possible for either of these guys to restore the mirrors.

https://www.decomirrors.com/re_silvered.html
http://mirrorresilvering.com.au

*A sextant is very basic instrument and mechanical instrument fitter worth their salt would probably be happy to use their skills to do any repairs necessary. These guys hide out in vintage car instrument / general aviation instruments / clock / gunsmith repair places. Sometimes you have to hunt them down .

[SeanPatrick]

Originally Posted by HankOnthewater

Anyone knows a place in Oz for this kind of repair/replace?

Bill Morris (the guy I mentioned up-thread) lives in New Zealand. I'm quite sure that he could help you find a reputable local who could do the job, if not help you directly.

Originally Posted by HankOnthewater

Thank you SeanPatrick for post #2, as always, your contributions are very helpful.

Always glad to help! Cheers!