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Re: Need Advice About Constructing Vacuum Coating System

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Posted by Rick Crockett on December 21, 2000 03:59:46 UTC

Hi Stephen:

Hearing your plans reminded me of the Demise of Arnold the Pig. Overing hearing something about " when pigs fly" he jump off the roof of the barn. The unfortunate event was rulled a "Suey Cide".

The shape and dimensions of that water bottle are all wrong for high vacuum. Vacuum bell jars must be stressed relieved and by cutting it you will introduce thousands of fracture lines. You try this, you are as dead as the pig. The Implosion will send shards through one or two walls and you will look like you were killed with a shotgun at close range. Unless you get lucky and the glass pops before much kenetic energy is stored. I have portholes that are made of tempered pyrex (prestressed instead of relieved) these are used as view ports in metal bell Jars and are 1" in cross section for a mere 6" dia..

Sputtering can take place in the (slang)High fives to minus six torr. With out Diffusion pump, coating will be full of pin holes. You are a long way away from doing this yourself. At least this time you asked before killing yourself.

Get to a library and start reading. Then see about working for a lab doing this.

Good Luck,
-Rick

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