Re: Chromium coating was ATM questions

[Nick Martin <bonnyton@ednet.co.uk>]

At 01:24 PM 6/21/99 -0400, you wrote:
>
>Hi Dragon,
>
>
>>
>>Here I am again, intending to make my first scope ( 8 " ) all by myself.
>>Now I'm still collecting the knowledge to do that. I have  some
>>questions.
>>Here, in southern Europe I don't know any service, workshop etc. which
>>is able to do aluminizing . But there is a chance to coat mirror with
>>Chromium, here in my town . As far as i know ( from ATM list ) ,
>>Chromium are' nt mentioned for that purpose.
>
>I would not think chrome plating would work. The layer of metal placed on a
>mirror
>is very thin.  I am not sure a plating process could be controlled that well
>nor with
>the uniformity of coating. 
<snip>
>David H. Bevel

If Dragon was referring to vacuum deposited chromium films. I have a
chromium coated optical window, I had done about 30 years ago intended for
use as a solar filter. The coating was not done evenly enough to be a really
good solar filter although it was dense enough (and not too dense) and free
from pinholes and gave a reasonable solar image. The coating is tough and
durable. It is still reflective after 30 years. Its only drawback maybe that
it is not as reflective as aluminium. It is worth a try though it is not
that much less reflective and it is a heck of lot more durable than silver.
 
Nick

Nick Martin, Bonnyton House, By Ayr, Ayrshire KA6 7EW ,Scotland, UK.
 Latitude 55 24'56" Longtitude 4 26' 00".
"Eppur si muove" Galileo Galilei