CRT Gaskets for Motorola 7 inch sets?
 

Hello, there seem to be lots of these sets around needing a replacement for
the rubber gasket that holds the front of the 7JP4 in place.

I think I remember reading a post here about this some time ago, and the question at the time was whether there's enough interest to warrant getting some new ones manufactured, hopefully with some new kind of material that won't 'melt' like the originals did. Silicon Sealer?

Any new information about this?

Hopefully this note isn't deja vu all over again for youse guys because I wasn't paying close enough attention.

Cliff

one of our members, Phil nelson, has a great restoration article on these 7 inch sets and making a gasket:

http://antiqueradio.org/motvt73.htm

Well, I consider my solution kind of a caveman fix, but it is functional and easy to do.

I recall the other discussion. I think it may have been in the Antique Radios TV forum, but that site's not responding today, so I can't search for it.

If someone has an intact original gasket -- yes, there are a few out there -- I think it would not be that hard to make a mold and cast a replica made of a flexible material. Smooth-On makes flexible products, for instance.

http://www.smooth-on.com/lifecasting.htm

I have done a little mold making & casting, and it's not rocket science. If you can make a flexible human arm replica, the gasket certainly wouldn't be impossible.

A couple of people have talked about contracting with a commercial company to make replicas. Nothing has come of that, as far as I know. I suspect that the cost might be prohibitive, and I'm not sure the final product would necessarily be better than something you could create in a home workshop. Once you had a mold, you could make repros at home for, maybe, $20 a pop in materials cost.

One consideration is that you wouldn't want to damage the funky original in the process of making your mold. I would simply cover it with saran wrap before making the mold, to make sure the mold material can't stick to it. So what if the final product has a few wrinkle marks in it? The gasket is hidden when installed. It just has to be functional, not beautiful.

In case anyone's curious, here are photos of an original in nice condition.

http://www.geocities.com/reevesradios/vt71.html

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Here's a pointer to the CRT gasket discussion in the "other forum."

http://antiqueradios.com/forums/view...ola+crt+gasket

Phil Nelson

Motorola 7JP4 gasket
 

Thanks for all the pointers. Less than half of the one I have is bad, so I wonder if I were to cast two halves could I join them together?
Never done any of the mold or cast stuff before.
~amateur...

20 years ago, MOST of them were still good. Now, only a very very few are good. So action is required POST-HASTE, if anyone wants to try a repro by casting from an original!

Charles

How about doing some careful measurements on your original, then making a new model out of modeling clay, which you can then use to make a mold? Once you have a decent mold, you can cast many repros from it.

Phil