Chemically removing oxydation?



#5

Hi,

I own an HP-45 with battery terminals which keep oxydizing, even after I have scraped off most of the "mold" (it is green on one terminal and blue on the other). The calculator works fine with the power cord.

Please advise on the use of chemicals to remove the oxydation. My own chemistry knowledge is somewhat rusty (seems appropriate in this case), I think maybe an acid would work, but that will pose other problems with the calculator.

Sincerely,
RJvM


#6

Quote:
I own an HP-45 with battery terminals which keep oxydizing, even after I have scraped off most of the "mold" (it is green on one terminal and blue on the other).

You did good by starting with mechanically removing off as much corrosion as practical. Dump and vacuum or blow it out.

This is from rechargeable (NiCad or NiMH) batteries? Use regular household vinegar. Some dilute it several times. For small parts (like a classic battery case with cells removed) I soak in an inch or so of vinegar in a 10oz glass. I then mostly fill the glass with hot water and use that solution on a cotton swab to clean out the battery compartment and terminals and stuff I don't/can't soak. You will probably see some foaming as the vinegar neutralizes the battery leakage.

Vinegar also works for alkaline cells, but a baking soda solution is the key for the older style.

It doesn't hurt to try the soda solution and if you don't see the foaming effect, and the deposits don't seem to dissolve, use vinegar instead.

Final step is best to do a total wash with distilled water, but frankly, wiping off the solution will 99.9% of the time be fine.

sdb

#7

Try Deoxit from Caig industries.. Their new line of Deoxit Gold is both a cleaner and a protector against future oxidation.. you won't get that with a vinegar solution.


#8

Quote:
Try Deoxit from Caig industries.. Their new line of Deoxit Gold is both a cleaner and a protector against future oxidation.. you won't get that with a vinegar solution.

Deoxit is for true oxidation (combination with oxygen) and dirt. It is less effective against deposits from leaking batteries, IMHO.

It would be good to apply Deoxit after cleaning and neutralizing the deposits as described.

sdb


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