The Talking Machine Forum — For All Antique Phonographs & Recordings

What are most members using to seal the diaphragm into the floating reproducers??

Blizz

I roll beeswax into a long strand like a spaghetti noodle, then insert around the edge of the diaphragm and press into place.

+1, except that I heat it so it will flow in for a better seal. Not sure if that is really necessary though.

Jim

Thanks for the replys..

blizz

Just wanted to add that I use that same method
mentioned by HMV.

But, as Jim said, a little heat seals it.

Specifically, when rebuilding recorders, I use
a little set of home made tools to get the
beeswax noodle pressed in, and then melted just
a tiny bit, to seal airtight to the mica.

I made a little set of tools out of thin
flashing aluminum sheet, and some from thin
galvanized sheet steel. They look like
a flat wooden toothpick, having a wider rounded end, and a narrower, more pointed end. Both
ends are rounded by gently working with tiny
files and emory paper until round and smooth.

These tools can be bent to suit whatever you're
needing to do to the wax to seal it.

I always have an alcohol lamp burning close by,
so I can heat the end of these tools before
working the wax with them.

One recorder I did some time back performed
only so-so after being assembled and sealed.

I could not figure out why, until I remembered
to go back and work all around the wax with the
heated tool, to melt the wax so it flows out
on to the mica just a tiny bit. I did that
step to that recorder, then tried it again, and
the difference was astounding.

If you get too much beeswax melted out onto the
diaphragm, it can be removed by gently scraping
it off using the other end of the heated tool
and having it bent into a shape that works
for that. Gravity is also your friend, so
tipping the whole works up so the wax wants
to flow down toward the edge helps.

It takes me at least 45 minutes to go completely around a recorder diaphragm while
doing that step.

Chuck