HP Forum Archive 16

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Spilled coffee on HP12C Message #1 Posted by K the A on 15 May 2006, 4:34 p.m. Ok, so I'm trying to remove the back from a 20-year old HP12C which got partially drenched in cold latte. I have the back off, but am unsure how to proceed from here. Want to dry the thing out completely as it is behaving badly. Any help would be appreciated!

Re: Spilled coffee on HP12C Message #2 Posted by Cameron Paine on 15 May 2006, 6:19 p.m., in response to message #1 by K the A Luiz Vieira and possibly Eric Smith are the Voyager opening "experts" who visit here often. I've never opened mine but I'm aware of the stumbling blocks: screws under rubber feet; EMI foil wrapper and heat stakes (rivets) holding the keyboard together. Until the experts weigh in, here's an article from the archives that talks about opening the 15C. It's a Voyager too although I believe it has two R2D2 chips whereas the 12C has only one. Cameron

Re: Spilled coffee on HP12C Message #3 Posted by K of A on 15 May 2006, 6:38 p.m., in response to message #2 by Cameron Paine Thanks for your help Cameron. I looked at the description on the 15C and realize I am not up to the task. I'll just let it dry overnight and (gasp) use another calculator in the meantime. Hoping that takes care of it. If not, maybe it's time for a NEW hp12C. Thanks again.

Re: Spilled coffee on HP12C Message #4 Posted by Cameron Paine on 15 May 2006, 6:45 p.m., in response to message #3 by K of A I'm sure we can get your coffee-soaked vintage 12C working although it will mean using a different one until we hear from the voice(s) of experience. There is often talk here of washing (as in immersion) calculators in various solutions of isopropyl alcohol and water. Why not check back here over the next few days and see what the vast amount of collective knowledge and experience can suggest. Don't write off your old faithful just yet. Cameron

Re: Spilled coffee on HP12C Message #5 Posted by Randy on 15 May 2006, 6:46 p.m., in response to message #3 by K of A First thing - GET THE BATTERIES OUT OF IT! Now that I have your attention, with the back off, dunk it in clean, warm, distilled water, swish around, push all the buttons while submerged. Do this several times - two or three water changes should suffice, depends on how much coffee got in. Shake very well to get all the excess water out and put in front of a small fan to dry for at least a day. It will be clean and good as new.

Re: Spilled coffee on HP12C Message #6 Posted by K of A on 15 May 2006, 6:59 p.m., in response to message #5 by Randy Okay, I'm going to try this, although it feels really unnatural to be dunking an electronic device in water! No alcohol? We have a water cooler (Culligan), will that water suffice, heated slightly in a microwave? I have a large bowl, and can do all this at work. I also have a fan in my office. So I think I can manage thus far. Just WATER? THANKS SO MUCH FOR ALL THE HELP - I would like to save this relic.!

Re: Spilled coffee on HP12C Message #7 Posted by Randy on 15 May 2006, 8:23 p.m., in response to message #6 by K of A Every electronic device you own has been washed in water or harsh solvents sometime during the manufacturing process. Water is the safest solvent available, it will not affect rubber and elastomeric components the way alcohol and other nasties can. Can alcohol dissolve sugar? Water can... Yeah, believe or not, just dunking it in a bowl of clean water is quite safe so long as it doesn't remain wet and of course the batteries are long ago out of it. Give it a bath, dry it out. It will live again.

Re: Spilled coffee on HP12C Message #8 Posted by Thomas Okken on 15 May 2006, 7:56 p.m., in response to message #5 by Randy Quote: dunk it in clean, warm, distilled water, swish around, push all the buttons while submerged. Sorry to butt in -- but I have seen this type of advice before, and I'm always wondering about water getting into the LCD. I have experienced the problem of dust getting in there, and not knowing how to get it out; so, when you say "dunk it in water", do you mean to submerge the calculator *all the way*, or should one keep the display part dry? (Here's hoping I never have to go through this exercise with any of my hard-to-replace vintage calculators, but I know that simply being careful is no guarantee that things will never go wrong. I can't help but remember that Commodore 64 that I once spilled a soda on. The keyboard was never the same afterwards.) Thanks, - Thomas

Re: Spilled coffee on HP12C Message #9 Posted by Randy on 15 May 2006, 8:33 p.m., in response to message #8 by Thomas Okken If the liquid crystal can't get out - how can the water get in? The dust is between the LCD and a protective window. Canned air works well for that. Sometimes a coated piece of paper (backing from a sticky label) can be inserted to dislodge stubborn bits of dust. In extreme cases (early Pioneers are the worst) I resort to the calculator washing machine AKA Ultrasonic cleaner. RE: Commodore 64. My daughter has a habit of spilling soda into her PC keyboard. When essential keys fail, we disassemble and wash in the bathtub. Dry overnight, reassemble. Current kbd is 3+ years old, been washed at least 3 times. Great family fun. PS: Beware of software weenies carrying screwdrivers :)

Re: Spilled coffee on HP12C Message #10 Posted by David Smith on 16 May 2006, 10:21 a.m., in response to message #3 by K of A DONT let it dry. Rinse it very well with several changes of distilled water. Use an ultrasoic cleaner if possible. Shake as much water out each time as possible. Then let dry (a hot car with the machine out of the sun or an open oven on LOW works well).

Re: Spilled coffee on HP12C Message #11 Posted by K the A on 16 May 2006, 11:29 a.m., in response to message #10 by David Smith David: Why do you say DON'T LET IT DRY???? I have followed the earlier advice and immersed it several times in warm distilled water, and it has been drying in front of a fan since last night.

Re: Spilled coffee on HP12C Message #12 Posted by Arnaud Amiel on 16 May 2006, 11:42 a.m., in response to message #11 by K the A I believe what must not dry is the coffee, though it might have been too late for you. Of course, your calculator should be thoroughly dry before you put the batteries back in. Arnaud

Re: Spilled coffee on HP12C Message #13 Posted by K the A on 16 May 2006, 11:53 a.m., in response to message #12 by Arnaud Amiel I'll post later tonight or tomorrow a.m. and let all of you know the outcome. I appreciate your time! ; )

Re: Spilled coffee on HP12C Message #14 Posted by Kiyoshi Akima on 16 May 2006, 12:47 p.m., in response to message #13 by K the A It's probably too late, and I'm not sure how applicable it is since this happened to a Woodstock (HP-25) back in the 80s. A friend lent his 25 to another friend, who promptly dumped coffee (or was it a soft drink?) on it. His girlfriend took into the nearest restroom, swished the thing around in the sink, and it worked fine. When it was returned to the original owner and the tale told, his first response was: "Well, I would have turned it off first before sticking it in the water."

Re: Spilled coffee on HP12C Message #15 Posted by K the A on 17 May 2006, 12:19 a.m., in response to message #13 by K the A It worked!!!! My HP12C is humming again...thanks to all of you who answered my plea, and especially RANDY since I followed your advice to a "T". I did the water immersion in distilled water and shook it out, and let it dry in front of a fan about 24 hours. You can't possibly know what a relief it is -- I use that dang calculator at least 25 times a day. THANK YOU!!!!! It's great to know there are kind souls like you all out there in cyberspace.

Re: Spilled coffee on HP12C Message #16 Posted by David Smith on 16 May 2006, 11:25 p.m., in response to message #11 by K the A You dont want coffee, soda, cat wizz, baby puke, or any other composite substance to dry in the machine if you can avoid it... it just makes it that much harder to remove... and may hasten corrosion, etc as it drys and concentrates whatever evil it contains.

Re: Spilled coffee on HP12C Message #17 Posted by K the A on 17 May 2006, 4:26 p.m., in response to message #1 by K the A Oops - I spoke too soon when I posted that things were humming again with the HP12C. Worked great for about 5 minutes this morning, then got stuck on a cleared screen "0.00" and won't budge. Could not even turn it off without removing the batteries. After the immersion bath, it dried for 24 hours in front of a fan. Does it still have coffee in there? Should I repeat the whole process again? Is it beyond hope? Does anyone have a decent HP12C they want to unload? Sorry to be a pest. I am forced to use Excel to do calculations today, and can't tell you what a drag this is.

Re: Spilled coffee on HP12C Message #18 Posted by Randy on 17 May 2006, 4:48 p.m., in response to message #17 by K the A Despair not. There was probably some water lurking inside a key. Get the batteries out of it and reopen, press all the keys and see if there is any sign of water. All little more drying time should do it.

Re: Spilled coffee on HP12C Message #19 Posted by K the A on 18 May 2006, 12:20 p.m., in response to message #18 by Randy Once again, thanks for your help Randy! I let it dry out overnight again next to a fan, and it appears to be working fine. I'm so relieved. THANK YOU

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