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Cleaning HP 41Cs



#3

Hello,

I would appreciate some recommendations for cleaning products
to use on a couple of HP 41 C's I am trying to bring back
to life.
One of them is VERY grungy, with a lot of graphite-like
stuff all over it. One of the battery terminals is also
rather green, and I guess I'll try the pencil eraser method
on it. Their cases are also fairly dirty, though the foam
seems in good shape. Can one wash those?
In looking over the forum archive, I've run across
people recommending/using:
SNAP plastic cleaner
diluted Simple Green

I have personally used ethanol and Q tips in the past, which
worked well (denatured alcohol), but I am trying to do a
proper restoration effort, so I am going about this slowly.

Any guidance will be much appreciated.

Happy New Year,

Ion Abraham
Albuquerque, New Mexico


#4

Plastic:

If it's _really_ dirty, start with a damp cloth. A little mild detergent may also help (note: a *little*).

Be very careful cleaning the LCD display. You don't want to scratch or crack it. A cotton bud (Q-tip) may be a good tool to clean it. It can also get around the keys, but be careful not to have it so wet that any liquid gets in beside the keys.

Battery contacts:

Start with an old toothbrush - dry.

After you've used these to get rid of all of what will come off easily, then go for the more aggressive treatment.

Try not to let any stuff from the battery contacts to fall inside the case. (But hey, you may need to clean in there too)


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