The Talking Machine Forum — For All Antique Phonographs & Recordings

Yes the mica diaphragms which are commonly available
at the present time all seem to be about .007 inches thick.

They also have the telltale grey color. They do however
have a very nice ringing sound when set down gently
on a flat surface.

Contrast that with the original .002 inch thick clear
mica recorder diaphragms commonly used on Edison recorders.

I have a rebuilt automatic recorder which has one of the
modern-day .007 inch thick grey micas in it. It talks
up fairly loud and clear, but it might work even better
with a thinner one or maybe glass.

Chuck

Regarding the stratena glue, the last search I did for it I actually found the listing (don't ask how because I'm not sure) but it had a note from ebay that it is no longer available. That pretty much settled that for me, so I ended up buying stick shellac for my recorder (I finally got the supplies to fix it )

Too bad about the stratena not being available.
According to Peter, it's not that hard to make a
batch of it. It has gelatin as the main ingredient.
Peter was using vodka as a source of alcohol when making
it, and he described to me one time how he'd pour a little
vodka in the glue batch, then drink some of it, pour a bit
more in, drink some more and pretty soon he was feeling no
pain!

He also mentioned the addition of a slight bit of boric
acid. So this all leads me to believe that if Peter is
really not making this great stratena glue any more
that it would not be too hard to figure out how to
make it. He said he was using Jello brand gelatin.
Not the flavored or colored kind. Just the plain stuff.

Chuck