On Feb 11, 18:49, Vintage Computer Festival wrote:
> Can anyone suggest a safe way to remove grime that is so old and so
thick
> that the only way to remove it is to rub it off with your bare
fingers?
>
> I slathered this board in contact cleaner and it didn't do anything.
The
> grime just remained. If I rub it with my bare fingers then it will
> eventually start to rub off and leave little remainders like pencil
eraser
> droppings.
Don't use contact cleaner. Proper contact cleaner contains oil. It's
not nearly as bad as WD40, but you don't really want the board covered
in a flm of oil.
If it's just one board, try washing it in warm water with some
washing-up liquid (dishwashing detergent). If the grime is that
stubborn, assist the process with a dishwashing brush. Rinse well, dry
carefully (shake off or blow off as much water as possible, use some
IPA to help remove the water). If you're in an area with very hard
water, the final rinse before the IPA might best be done with distilled
or deionised water. Don't dry the boards flat, the object is to let as
much water (and any minerals dissolved in it) as possible to drain off.
Make sure the board is thoroughly dry, which may take a day or two,
especially if there are switches or sockets on it, before you try to
use it.
If that's too much like hard work, or you have a lot of boards to
clean, consider using the dishwasher. That's what's used commercially
(at least, for small-scale stuff). However, DON'T let it do the drying
cycle (too hot for some things) and don't use the dishwasher if the
board contains anything that might suffer: transformers, relays (unless
hermetically sealed), paper labels that must be preserved, anything
with extremely fine wires (core mats), etc. I've been told some very
old ICs (grey type) don't like being immersed in hot water. I've never
had a problem with that, but YMMV. Some old types of compressed paper
boards (Paxolin) may not like the dishwasher either. Same rules apply
about drying.
--
Pete Peter Turnbull
Network Manager
University of York
Received on Wed Feb 12 2003 - 00:31:00 GMT