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HP Forum Archive 20

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Cell leakage in my 48S
Message #1 Posted by Palmer O. Hanson, Jr. on 14 May 2011, 11:41 a.m.

I left the cells in my 48S longer than I should have. One of the cells leaked. The leakage got into the foam that provides the spring for the cell contacts. The leakage dissolved (if that is the correct word) the adhesive that attached the cell contacts to the foam. I have cleaned the compartment and have demonstrated that the calculator still works by simply holding the contact against the foam while inserting the cells.

I think that some of the leakage is still in the foam. How can I remove the leakage safely? What adhesive should I use to attach the contact to the foam? If I replace the foam where do I find foam that does not deteriorate in a few years?

Separate subject: If you wonder why H-P doesn't always implement your latest good idea I suggest that you read the article "Creation Myth" in the May 16 issue of The New Yorker.

Re: Cell leakage in my 48S
Message #2 Posted by geoff quickfall on 14 May 2011, 3:23 p.m.,
in response to message #1 by Palmer O. Hanson, Jr.

I find the old thick mouse pads have the correct width. So:

1  remove the old foam and glue.  
2  Slice out a new chunk of foam using the original as a template.
3  attach foam to metal tab to foam with double sided tape
4  attach foam to calc with same.

Cheers, Geoff

p.s. replace batteries every 5 years ;-) (just kidding)

Edited: 14 May 2011, 3:23 p.m.

Re: Cell leakage in my 48S
Message #3 Posted by Katie Wasserman on 14 May 2011, 4:11 p.m.,
in response to message #2 by geoff quickfall

Almost any high-density foam work in this calculator and likely last many years. I've had some small peices of Dow Ethafoam that have lasted for 40+ years with no obvious breakdown. It's not hard to find, but is relatively expensive. Here's some.

To avoid the battery leaking issue, I would suggest using Energizer lithium cells. I've never seen one leak and I've had hundreds of them in my calculators (and just about everything else the needs AA or AAA cells) for many years.

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