HEY I have got several HP-32S that I bought around 1990,
and those stinkers almost IMMEDIATELY began to accumulate household dust in their display.
Now one guy just said "dont use an air compressor it always contains oil and moisture" and I want to disagree with that.
If you happen to have chosen an oil-less air compressor you can get some really nice dry air out of it. I chose oil-less for my garage-shop and have no regrets that the air is always clean & dry. Some of the metal-shop guys chastise me because the air-tools dont get lubricated. Thats what a hand-oil-can is for. Just put some drops right into the inlet of the tool. And about dryness, humidified air loses its moisture under pressure, thats why a puddle of water accumulates in a compressed air tank. Thats why any knowledgeable owner of an air compressor installs an easy-access ball-valve at the bottom and operates it often. Its even a safety issue to reduce the likelihood of a tank rust-through. Meanwhile when the air comes out the gun it is DE-pressurized, it is very dry because its been thru, effectively, a pressurized dehumidification process. The remaining risk is specs of debris in the hose, but the odds are in your favor there wont be much of that.
Therefore at my shop, the air compressor is the FIRST
THING I would reach for, not the last.
LASTLY, does anybody else have further info about how to clean out a 32S ?? I am not real enthused about the compressed air because it does not solve the real problem. I think you need to get in there and clean it out for real and maybe seal it, IF thats possible, I never tried but wondering if anybody else did (for reasons of house dust).
Although we are supposed to bow down and worship the might HP Calculator Gods, I think they are buffoons in regards to dust getting in the display. I was disappointed even around '92 when the dust in the display was appearing, I mean, '92 was hardly a medieval era, and it was a substandard design to have something so ridiculous as
the display get dirty from the inside.
Modern equipment tests for new designs include
(a) test for electro-static-discharge immunity with a spark gun
(b) test for radio-frequency susceptibility or transmissions
(c) test for durability. This is often done by putting the unit in a tumble-dryer with a variety of objects and some house dust and grit. It has to get tumbled awhile and still be useful in the end.
Looks to me like HP didn't do any of that for their supposedly superior modernized "LCD" calculators or I wouldn't be asking about the dust in the display.
I'd wager that the red LED HP-34C is more likely to pass the dust-in-the-display test. (NO you cant test mine!)