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Less On Money

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Posted by Anthony Kight on August 19, 2000 17:40:40 UTC

If I might change the subject from money and the need for it for a moment, I could use some advice on an idea I have been toying with.

I would like to grind a 12"F6 for a Neutonian however my understanding is I will need a mirror blank about 2" thick. Due to the cost of such a blank I have been considering bonding several layers of .5" plate glass to a .75" peice of plate. I am a dental lab tech and know of many light cured bonding agents that are used to bond porcelain veneers to natural dentition. The composition of the porcelain is mostly quartz with fieldspar and other natural glasses. My theory is that if I can bond one layer at a time it would be possible to make a blank out of fairly inexpensive glass. I calculated the depth of cut on the first piece of glass to be about .1249"deep so I rounded this number up to .3" deep after figuring. This would mean that the first piece would need to be .75" thick to avoid grinding through to the bonding agent.My concern is this: as the mirror changes temprature, will it remain stable? Will the super thin layers of bonding agent between each layer of glass also work as an insulating agent forcing the glass layers to expand and contract differently between each layer of glass. Has anyone tried this?? Any advice or input would be appreciated. Clear Skies.

I wish it was clear skies here in Idaho half of my state must be on fire right now beautiful sun sets but poor visability of the stars.

Thank you in advance, Tony.

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