Re-manufacturing rubber pinch rollers?

[CJay]

Pinch rollers for analogue video and audio were really quite precisely made items, they had to be, there was no clock to re-sync and the 'data' was 'real time' so there's no way to correct tape transport aberrations which, as someone else pointed out, produces unpleasant side effects so I'm really interested in seeing the results of any attempt to re-cast them.

I reckon it's going to be really difficult to do but I hope to be pleasantly surprised as I've a couple of old tape decks I'd like to get going again.

One idea that does occur to me would be to remove the old rubber then cast the original metal core roller into some hard plastic and machine it down to true it, once that's done it might be possible to sleeve it with silicone rubber or perhaps even 'dip coat' it?

[AndyC_772]

I'd be quite interested to understand why it is that some rubber parts seem to stand the test of time OK, while others go hard and others become sticky.

One of my occasional pastimes is restoring audio DAT decks, and when the pinch roller starts to go, the bit error rate creeps up until the rf signal becomes impossible to lock on to and decode properly. The odd thing is that, even though most of the machines I work on are from the mid '90s, a roller from one machine can be in much better condition than another, even when the mechanisms are identical.

[mikeselectricstuff]

Rubber or silicone tubing maybe ?

[floobydust]

MG Chemicals Rubber Renue I used in the repair shop use on old pinch rollers and platen rollers. It's a 'must have' if you are working on old cassette decks, reel-reel, turntables, printers etc.
Techs told me to never use it on belts, but MG says it works there. I thought it can make the belts swell.

[CatalinaWOW]

May be different environments.  Remember Bob Pease's discovery that air ionizers ate all the rubber seals in his house?  So one deck that lived in a smoggy city, or a freshly painted house, or ... dies, while another got better, cleaner air.

[Astrodev]

From a recent discussion I had in a shoe shop it appeared that for some shoes with man made soles there could be significant deterioration of the soles if stored in their boxes, whether worn or not.

I have got a couple of pairs where the soles have gone tacky and one that has developed cracks even out of the box, but at the same time I have noticed that cassette deck and turntable belts do not last as long as I would expect and rubber bands have a very short life expectancy before going brittle.

All this supports the idea that the environment plays a big part in how long we can expect these components to last, I am glad I only use digital systems for recording these days, as I hate to think of the amount of hassle all the drive belts on a multitrack tape deck would cause having to be replaced regularly.

[wilfred]

From a recent discussion I had in a shoe shop it appeared that for some shoes with man made soles there could be significant deterioration of the soles if stored in their boxes, whether worn or not.

Yep. That happened to me. I thought I was really clever buying a decades worth of shoes I liked when they were cheap and discontinued.  After 5 years they just disintegrated on initial wearing. In the literal sense of the word.