Variable condenser part wanted
jstrohm at TEXAS.NET
Sun Jul 22 15:44:33 EDT 2001
Fred Holnagel <w7prv at JUNO.COM> writes...
>one of the ceramic bars on the stator section is broken...
> I could make one of Lucite but not sure of the
>dialectric properties. Any help would be appreciated!
If you have a porcelain or ceramics shop nearby, you might see if you can
get a few ounces of porcelain and some kiln time.
Making a suitable replacement from porcelain clay is trivial; making an
exact duplicate is not too hard. Unfired porcelain ("green" ceramic) can
be machined just like soft metal if you drill, tap, weharever before it
gets too hard. And usually the shrinkage diuring firing is minimal enough
that it doesn't matter -- make the holes a wee bit oversize, and "egg" them
slightly to give yourself some leeway for shrinkage.
You can also use teflon stock, which is kind of expensive and hard to come
by, but has EXCELLENT machinability and dielectric properties, and stands
up very well to heat.
If you have an acetylene torch, you can also fuse glass into the right
shape and punch homes in it. It cuts and forms like taffy when it's hot
enough to flow. Not exactly a do-it-yourself material, but a good option
if you happen to have the torch.
I've had pretty good luck with using krazy glue to mend ceramic capacitor
insulators, but I've always had all the pieces.
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