Rock hard rubber softener?

[Curt A]

Here is a testimonial from a user of "Rubber Soft" on eBay:
“Items Softened-These are gaskets that go on the back of Exhibition and No. 2 Victor Reproducers. Most of them are 100+ years older and hard as a rock. Buying a new one is about $15 so if I can soften and recondition the originals it makes a rebuild less expensive. I had a few lying around so I tested how long to leave them in the solution for. 6-8 hours seems to be about right as any longer makes them too soft and they fall apart.”

Has anyone used this stuff? I bought something similar from Germany for softening the rubber gaskets on my BMW convertible top and it worked great...
https://www.ebay.com/itm/16-oz-Rubber-S ... 0005.m1851

[tim w]

Once I was talking to a couple car mechanics. They said brake fluid would swell up rubber. I had a first style ultona sound box that I couldn’t pry apart. I smeared some on the exposed gasket. After awhile it did seem to get softer. I don’t know what it does to the structural integrity. But it might be a cheaper alternative to experiment with before you take the plunge into something more expensive & harder to get.

[jukejunkie]

A friend of mine is a typewriter collector and has a product for softening the hard rubber on the platens. It works well but stunk to high heaven for a week or two. He is on this forum and might post the name of it.

In the olden days' we used to use carbon tetrachloride on motor idler wheels but am sure that is no longer available.

Kurt M

[CarlosV]

I tried the mix of wintergreen oil and alchool, with different results. The positive outcome: after soaking overnight a rock-hard exhibition rubber back, it turned flexible and recovered its original grey color. The negative: I did the same with a decrepit rubber connector of a Pathé soundbox, and it ended up mushy. The nice part is that it smells good.