buttons that don't register well

If you're having problems with the hardware of a DM41X or DM42, post about them here.
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Walter
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Location: On a mission close to DRS, Germany

Re: buttons that don't register well

Post by Walter »

gruensucher wrote:
Tue Dec 19, 2017 10:19 pm
Woher soll ich wissen, was du hier meinst, wenn ich nur lesen kann, was du schreibst? :? :roll: Irgendwie widerspricht das dem, was du um 20:29 Uhr geschrieben hast. Oh, die Welt ist voller Rätsel! ;)
Hmmm, ich lese und lese, wo gebe ich Dir Rätsel auf?
Ganz einfach: Um 20:29 empfiehlst du "Bremsen- & Teilereiniger" und rätst von Aceton ab. Um 21:49 schreibst du wörtlich "Ich benutze kein Aceton, vorzugsweise als Teilereiniger." Ist meine Verwirrung nachvollziehber?
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
mcc
Posts: 277
Joined: Fri Jun 23, 2017 5:10 am

Re: buttons that don't register well

Post by mcc »

Hi,

(sorry I am no native speaker, and technical stuff is even more difficult to me to express...)

something, which came into my mind reading of "cleaning electronics":
Even if things may work great in the moment, they may become even worse
later (half a year or even longer).
Reason: The solvents may contain "addtional substances" which help for
the intended usage of that solvent but are bad for the current one.

Aceton: Highly aggresive solvent. Eats nearly everything called "plastic".
Good solvent for grease.
Nail polisher: Often this is Aceton mixed with oils, so that the nails do not
loose to much of it. After the Aceton evaporises, the oils remain. And they
do that everywhere...also in the calculator.
Any technical solvent, which is made for "coarse mechanics" should only be applied
to "coarse mechanics"...again the reason are "addtional substances".

To clean "delicate electronics" and "fine mechanics" I would prever pure substances
from the pharmacies. Propan-2-ol, 2-Propanol, Isopropanol, "Isopropylalkohol" (german word),
is great for removeing oily and greasy stuff. It cannot remove oxyds, though.

Even methylated spirit contains other substances than Methanol, which remain in the calculator like
tannin (it is added to the alcohol to denature the alcohol -- it is tasting very bitter...).
And tannin is a (weak) acid.

Cheers! :)
Meino
DM 42 - SN: 00373, Firmware release v.:3.22. / DMCP 3.24. as compiled by SwissMicros
AlexFekken
Posts: 10
Joined: Wed Jul 26, 2017 7:58 am

Re: buttons that don't register well

Post by AlexFekken »

Walter wrote:
Tue Dec 19, 2017 11:08 pm
gruensucher wrote:
Tue Dec 19, 2017 10:19 pm
Hmmm, ich lese und lese, wo gebe ich Dir Rätsel auf?
Ganz einfach: Um 20:29 empfiehlst du "Bremsen- & Teilereiniger" und rätst von Aceton ab. Um 21:49 schreibst du wörtlich "Ich benutze kein Aceton, vorzugsweise als Teilereiniger." Ist meine Verwirrung nachvollziehber?
Maybe the solution to your riddle is a missing comma after preferably (vorzugsweise)...?
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Walter
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Re: buttons that don't register well

Post by Walter »

AlexFekken wrote:
Wed Dec 20, 2017 5:33 am
Walter wrote:
Tue Dec 19, 2017 11:08 pm
Ganz einfach: Um 20:29 empfiehlst du "Bremsen- & Teilereiniger" und rätst von Aceton ab. Um 21:49 schreibst du wörtlich "Ich benutze kein Aceton, vorzugsweise als Teilereiniger." Ist meine Verwirrung nachvollziehber?
Maybe the solution to your riddle is a missing comma after preferably (vorzugsweise)...?
One riddle more instead of a solution... :?

I'd really appreciate if posters would read what they posted themselves. Thoroughly. Always. Reliably.
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
keithdalby
Posts: 564
Joined: Mon Apr 24, 2017 8:38 pm

Re: buttons that don't register well

Post by keithdalby »

Walter wrote:
Wed Dec 20, 2017 6:22 am
I'd really appreciate if posters would read what they posted themselves. Thoroughly. Always. Reliably.
Accidents happen though, and I make mistakes frequently enough that I dare not take your side on this.
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Walter
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Re: buttons that don't register well

Post by Walter »

keithdalby wrote:
Wed Dec 20, 2017 7:18 am
Walter wrote:
Wed Dec 20, 2017 6:22 am
I'd really appreciate if posters would read what they posted themselves. Thoroughly. Always. Reliably.
Accidents happen though, and I make mistakes frequently enough that I dare not take your side on this.
No problem with accidents, mistakes, errors, faults, flaws, etc. I make them as well. But each person is responsible for its posts as well as for the mistakes etc. in it. And it's seldom too late to use the EDIT button this forum generously offers, isn't it? Please!
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
jfb9301
Posts: 21
Joined: Mon Dec 11, 2017 12:33 am

Re: buttons that don't register well

Post by jfb9301 »

Quoted from above:

"Isopropylalkohol" (German word)

German is so close to the the English. You are looking for "Isopropyl Alcohol". Oddly I noted if you use Chrome as your browser it does not recognize Isopropyl as spelled correctly, but if you google search the word, google search does.

As to what to use to clean electronics. I worked in electronics repair for over 20 years. I agree with basically what has been said.

1. Do not use acetone, it eats away at things you don't want eaten.
2. Nail-polish remover is generally acetone with other ingredients, so really don't use that.
3. Do use a non-Methanol based alcohol. When you buy it, you will often note that it is 80% alcohol and 20% distilled water, I would use that in a pinch, but I don't like that much water. if you can find 99% or 100% Isopropyl Alcohol, grab that and use it.
4. Cleaning compounds like carb-cleaner and brake cleaner, nope not that. Oil and other stuff.
5. (Electric) Motor-cleaner. May have impurities, but if you have a really dirty contact it will work, still I would generally advise against this one.
6. (Electric) Contact-cleaner. If alcohol does not get the job done and you still have trouble, this is the best thing you could use. Low to no impurities. This stuff will clean even the most stubborn oxidization and other stuff you cannot see, but is interfering with good contact. I do caution if you use this or the motor cleaner, us in a WELL VENTILATED space, the fumes are strong and possibly toxic. A suggestion to look for on this would be KC Contact Cleaner.
zooropa1844
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Re: buttons that don't register well

Post by zooropa1844 »

I have just opened my calculator and cleaned the contacts and domes of two of the keys. I used what I had at hand 96% alcohol for injuries. It worked nicely. Now they work in the right way without any extra force needed.

I keep having problems with the Enter key. Only works right on its left side. On the right side, keystrokes are recognised but no hactic feedback or click sound at all. I haven't tried anything related to this key since I haven't read any solution to this type of problem.

Kind regards,

Javier
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revwillie
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Re: buttons that don't register well

Post by revwillie »

zooropa1844 wrote:
Wed Dec 20, 2017 7:12 pm


I keep having problems with the Enter key. Only works right on its left side. On the right side, keystrokes are recognised but no hactic feedback or click sound at all. I haven't tried anything related to this key since I haven't read any solution to this type of problem.
there's a screw right behind the enter key. try backing that screw out 1/4 turn. repeat until it works better.
DM42 SN: 00076
DM15, HP 28c, HP 12c, HP 10b, HP 20b, HP 30b, HP 17bII, HP 42s, HP 35s, WP 34s, NP-25, TI-83+, teenix multicalc
zooropa1844
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Re: buttons that don't register well

Post by zooropa1844 »

Sorry, but where that screw is exactly. Under the first plastic layer of the keyboard, you have the domes and the contacts on one side of the PCB. Do I have to remove the foil and clear the dome to see the screw?

Thank you, in advance, for your support!

kind regards,

Javier
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