Removing decayed foam in MX300 radios?

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Astro Spectra
Posts: 669
Joined: Sat Sep 22, 2001 4:00 pm

Removing decayed foam in MX300 radios?

Post by Astro Spectra »

Has anyone found a good solvent to remove the gungy and rotten foam often found in MX300 units, usually holding the elements in place?

In restoring one of these 30 year old veterans I'd like to clean up the sticky mess in what is otherwise an utterly pristine interior without endangering any of the other components.
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Tom in D.C.
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Joined: Tue Sep 04, 2001 4:00 pm
What radios do you own?: Progreso soup can with CRT

Re: Removing decayed foam in MX300 radios?

Post by Tom in D.C. »

My two starting points for removing "stuff" like you have
are denatured alcohol or, if that doesn't work, turpentine.
It's all a process of elimination if those two don't work, moving
on to nail polish remover, which is an acetone compound, then
409, Goo Gone, etc. I've even used lighter fluid at times.

And lots of Q-tips to keep the stuff from getting where you
don't want it to get.

The really frustrating part of cleaning up inside an MX radio is
when the foam junk deteriorates on the label of the crystal so
you can't read the data on the label. Ugh.
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
motorola_otaku
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Re: Removing decayed foam in MX300 radios?

Post by motorola_otaku »

I've noticed that STX radios suffer from the same rotten foam problem. Got any suggestions for what to replace the foam with? I've got a couple that are good performers, but are starting to suffer from microphonics.
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Astro Spectra
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Re: Removing decayed foam in MX300 radios?

Post by Astro Spectra »

Thanks Tom, Isopropyl alcohol (IPA) seemed to do the trick when used on a tooth brush.

For replacement foam, I found some suitablly squashy stuff at work but I don't know where it came form.

Cheers, John
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