Posts: 673
Threads: 20
Joined: Oct 2008
Get an old tooth brush and start with some distilled water (hell, its a Ti, you can use tap water for all I care!)
Open the case to get a better view of the rest of the board, or not!
Scrubb it and then rinse. Then, you might try some jewelery cleaner and scrub again in the battery pack area. You may just want to use Q-tips and clean the battery contact area. This is to prepare for a battery solder attachment.
Can you solder?
Buy a cheap 4.5 V phone battery pack from Radio Shack (You do have the charger, don't you?). Solder in onto the two battery terminals (Check http://www.ti59.com/ for details or information). The Ti-58 is basically a Ti-59 without a card reader and half the memory.
All of this can be for naught as the 58 could have further corrosion inside that may have ruined the traces between chips or even bad chips due to over Voltage or abuse in the past. Looks can be decieving.
Posts: 415
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Joined: Jan 2005
First: the "crystal stuff" is toxic and you should not touch it - besides that, it is not environment-friendly (aka toxic waste)
But as already suggested: the "white crystal stuff" is solvable by water; the hotter the water, the better it is solvable (hot water from the tap does the job). The "colored crystal stuff" is possibly not easily solvable, some physical force has to be used. The metal is very likely corroded and should be treated carfully, as it is weakened, springs and contacts might break when treated with too much force.
Posts: 75
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Joined: Jan 1970
While waiting for a reply here I googled and got a pinball/jukebox site that says to use 50/50 white vinegar/pure water for alkalines. Another site says alcohol/acetone for the nicads. The white stuff shouldn't be a problem but the blue crystal corrosion that is growing around the battery contacts, some traces and solder connections may be fatal. Thanks Ron and Frank, I'll use your suggestions, too.
There is not even a slight build up of greasy dirt around the keys so I think the calc had little use. A shame if the lack of use killed the calc. There was a RPN module available, maybe so HP users could use the TI.