[Amps] Non-vacuum capacitor

[Chris Wilson]

> Hello all,

> My wife has a woman working for her at her art gallery that is also
> an experienced 'glass artisan', or whatever the name is, and I asked
> her about working with the glass vac variables.
> She thinks the biggest issue may be not knowing the specific glass
> composition you would be working with.  The problem is the
> coefficient of thermal expansion, between the original glass and any
> glass tube (for re-evacuation) you try to melt to the capacitor.

> She has the high BTU output torch and skill working with glass,
> which are two things I don't have.  If I can find a vacuum cap that
> has lost it's vacuum, she is willing to give it a try.  And, we have an sneaking oven, as well.

> Does anyone have any mfgr documentation that may indicate anything
> abt the glass used (e.g. '... Using the highest quality Boron-Manganese glass...')

> 73 de Steve, NR4M




29/04/2013 16:10

The glass capsules will be pre blown and assembled and sealed up cold,
heating the glass envelope of an assembled cap to the point of
localised entry is going to knacker the seals, I am pretty sure!


Race shock absorbers (dampers) have a nitrile membrane a quarter of an
inch thick or so, through which they can be recharged with nitrogen.
They "self heal" as the hypodermic charging needle is removed. I can
see no reason why a similar sort of port couldn't be used in the
manufacture of vac variables, but holding vacuum instead of pressure.
I wonder if new ones are serviceable and can be re-evacuated at their
manufacturers, or if they just bin them if they leak?

-- 
       Best Regards,
                   Chris Wilson.