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how to make a secondary mirror

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#1 Duartealex

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Posted 22 May 2012 - 05:40 PM

Hi all,
I have blocks already cut side, now I have to know how they stay flat, these two blocks are more plans that did consegui.Eu flatness test plan with precision 1/4 lambda I won.
Could someone explain to me quite sure how I should do to make my plans side mirrors?

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thanks

#2 Mark Harry

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Posted 23 May 2012 - 07:07 AM

You need to mount them on a block, with a surrounding glass, like these pics. I used beeswax. They are small.
Beeswax isn't very stable, so once you start, it's a good idea to finish them within a day or so.

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#3 Mark Harry

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Posted 23 May 2012 - 07:11 AM

The one above, was a 1" MA, done singlely.
The ones below were done as a 3-spot block. The test was done next morning, but you can see how the individual pieces moved slightly overnight. It helps to have a good reference flat to test with. Make sure you mount them and the blocking on a secure and firm backer, such as an aluminum disc. Mine are 1" thick.
M.

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#4 Duartealex

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Posted 11 June 2012 - 01:24 PM

I wonder what moves should I use them to make plans. And what color should I use light to highlight the more franjas.Lembrando I have two plans with precision 1/4 lambda.
Is there any link that explains how to do everything right?

Thanks
Alex Duarte






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