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PKay
15-03-2018, 01:04 PM
Hi All

My 12" lightbridge mirror has had a makeover done by Dr Wayne from Saintech Ion Beam System.
It looks great, very shiny and new!!

I have a question.
The mirror sits on three triangular plates. Each plate has three discs of thin plastic about 15mm in diameter.

The discs look like they may have originally been glued to the mirror.
It's hard to tell.
I am thinking of using new discs out of double sided tape??

Any ideas?

Saturnine
16-03-2018, 12:10 AM
Peter
The Lightbridge obviously a 9 point floating mirror cell, the triangular plates should rock slightly, the reasoning being that as you place the mirror in the cell and on to the 9 discs, the plates will find an equalibrium to distribute the weight of the mirror evenly on to the 9 pads. Thus not introducing any stress to the mirror which could deform it's figure. The mirror only needs to be deformed by a few 10ths of wave to compromise its performance. No need to use any double sided tape though I have heard of mirrors being attached to the cells by velcro. An no stress mounting system so that the mirror is not deformed by the mounting system and is held firmly in place as the scope is moved around the sky.

PKay
16-03-2018, 08:13 AM
Thanks for the advice Jeff.
Upon close inspection, I think the plastic discs were not stuck onto the mirror.

Saturnine
16-03-2018, 10:57 AM
Pretty sure they wouldn't have been, otherwise they would have come away from the triangles when you removed the mirror prior to sending for recoating.