On Sunday 10 August 2008, Tim wrote: >On Sat, 2008-08-09 at 21:20 -0400, Matthew Saltzman wrote: >> *Denatured* alcohol! > >Yes. For those unfamiliar with the term, the usual cleaning alcohols >that you can buy are deliberately *poisoned* to stop people drinking >them (go figure!). I had to convince the local pharmacist to give me >some untainted alcohol at one stage. Later on, I had an even hard time >convincing customs and excise to let me buy pure alcohol. They only >relented after telling them about how poisonous and dangerous the >alternatives were. > >That tainting is bad news for cleaning video and audio heads. They can >be used, if you're desperate, and you wipe things clean and dry, instead >of just letting them evaporate. They contain a variety of things that >you don't want left behind on the heads, and that's very easy to do. >You're much better off finding something more appropriate. > >Be especially careful cleaning anything plastic or rubber, solvents can >destroy them. Remember that on the audio heads, at least, the head >block unit might have the magnetic part of the head embedded in a >plastic material. > >Do NOT use turps. > >> And a Q-tip. > >No, unless you're familiar with cleaning video heads, I wouldn't >recommend them. You stand a good chance of snagging fibres on the head. >Especially the tiny little things in domestic machines. > >The old rule of thumb was to use a chamois, but it's hard to find one >that's not oil soaked, and the artificial ones mightn't be suitable, >either. > >Like Gene, I work in this industry. But I don't think I'd be keen on >using paint thinner, though. I think they still use glues within the >head drum to hold the tiny parts of the head in place. The monster >sized heads from old two-inch quad VTRs, and even the one-inch machines >are very different from the tiny things in Beta and VHS. It works fine Tim, and at circa $8 a quart, or $17 a gallon at your local ACE Hdwe, is a heck of a lot cheaper than paying $5 at the shack for a 2 oz bottle that probably has some methyl chloride or MEK in it too, neither of which is good for humans or required to do the job. FWIW, the painting business also requires quite pure, contaminate free solvents, purer then the stuff you buy by the 55 gallon drum to mix with nitromethane for your 1/4 mile monster. This is not ethanol, but methanol. ethanol is drinkable and will work but you have to buy it at the liquor store, usually wearing a Phillips 190 proof label. Methanol is poisonous and works equally well but without the liquor taxes. The ACE Hdwe version comes in a handy container that can be carried to the job. Its also far less damaging over the long term to the pinch rollers than Freon TF ever was, when I switched, pinch roller life quadrupled. Freon TF seems to cause them to swell unevenly in the presence of any lubricant leakage at all, whereas the alky seems to wash it away better, prolonging the life of the elastomerics euphemistically called rubber. -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Drinking makes such fools of people, and people are such fools to begin with, that it's compounding a felony. -- Robert Benchley -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
