On the question of what to clean with what, I'm basically in agreement with the other posts above: use head cleaner (or really pure alcohol) on all the
metal parts that the tape slides over. The most important is the tape heads: record, play (if you have a separate play head) and erase. It pays to keep the various guides that tape runs over, and the capstan, clean too.
For rubber and plastic parts -- most importantly the pinch roller -- I personally use Tascam's rubber cleaner. I've heard the Windex recommendation from various sources, and it's probably a good one, so far as I can tell. I generally don't clean the pinch roller nearly as often as the heads and metal parts, though. On the reel-to-reel decks that I have, the pinch roller makes contact with the back of the tape, and the capstan's on the oxide side. With cassette decks (and some reel decks) it's the other way around, which I suppose is a factor. But I worry a bit that "overcleaning" the rubber may do some harm.
A Tascam rep did once claim that
only Tascan rubber cleaner should be used on rubber, and that even distilled water could harm the pinch roller. Personally, I'd take that with a grain of salt, though (no -- I don't mean a grain of salt in the distilled water!).
NYMorningstar said:
Alcohol is the most common solvent,
I'm pretty sure water is the most common solvent. It's sometimes referred to as "the universal solvent," although that may be overstating things slightly.
and the most universally safe on tape recorder or duplicator parts. It certainly doesn't desolve the pinchroller. Maybe you're thinking of acid, or taking it? ...
Alcohol's great on metal parts, so far as I know. However, quite a few people do report problems with pinch rollers that turn into something like gummy bears (or worse). I don't know that it's alcohol that does this, but I'd be pretty careful one way or the other. Actually, the rap on alcohol -- or head cleaning fluid -- and rubber is that it makes the rubber hard and slick, which I suppose
is the opposite problem.