Re aluminizing/Silvering

[Dom1961]

How often to do this and where can i do it? can i do it myself?

[michael.h.f.wilkinson]

If you want to silver a mirror this can theoretically be a DIY job, but I would personally not go that way. Aluminium is usually vacuum deposited, so unless you have a spare vacuum chamber, I doubt you could do it yourself. How often it is needed depends on many things, but many mirrors last 25 years before requiring attention. Stored under bad condition this figure drops rapidly

[damnut]

Seconded !! Along with a coating of aluminiunm there is usuall one of silicone / quartz  to protect the aluminium which in its pure form rusts before your eyes!

Link to Orion optics :-- http://www.orionoptics.co.uk/OPTICS/mirrorrecoating.html

Galvoptics :-- http://www.galvoptics.fsnet.co.uk/telescope7.htm

[Astrobits]

Seconded !! Along with a coating of aluminiunm there is usuall one of silicone / quartz  to protect the aluminium which in its pure form rusts before your eyes!

 

Link to Orion optics :-- http://www.orionoptics.co.uk/OPTICS/mirrorrecoating.html

 

Galvoptics :-- http://www.galvoptics.fsnet.co.uk/telescope7.htm

I hope no-one tries to use Silicone to overcoat their mirror. The usual overcoat is Silicon Dioxide ( aka quartz/sand in it's larger lumps ). It is not evaporated directly but Silicon Monoxide is evaporated onto the mirror and that reacts with the oxygen in the air to form the Silicon Dioxide in situ on the mirror surface. This takes a day or two and the mirror surface is more delicate during this period.

The simple addition of an 'e' to Silicon refers to a completely different substance. Silicon is an element while Silicone is a long chain molecule (which includes Silicon atoms) and it can cure by interaction with water vapour from the air to form a rubbery material.

Nigel

[michael.h.f.wilkinson]

Silica is another word for silicon dioxide. It is often confused with silicone.

[damnut]

I removed Si02 silicon dioxide from the post and left the residual 'e', as can be misleading and left silicone. Any click through to both Orion / galvoptic would gave the correct nomenclature. I think 99.999999% of folk would know not to coat a mirror with any form of silicone sealer, or mixed inorganic - organic polymeers aka  polymerized siloxanes

Mind you there is always one!

[Astrobits]

I removed Si02 silicon dioxide from the post and left the residual 'e', as can be misleading and left silicone. Any click through to both Orion / galvoptic would gave the correct nomenclature. I think 99.999999% of folk would know not to coat a mirror with any form of silicone sealer, or mixed inorganic - organic polymeers aka  polymerized siloxanes

 

Mind you there is always one!

Precisely.

And don't forget that not everyone will search for a U.K. re-aluminising service, especially if they live elsewhere in the world.

Nigel