HP 28 with battery corrosion

[MattiMark]

A friend of mine has gotten battery acid in his HP-28 (forgot the batteries in the calc for just too long) . And it´s just dead when using new batteries. Is there a way to rescues the calc? How can it be opened?

Regards,
Matti

[Paul Dale]

If the corrosion isn't too bad, try spraying deoxyit on the contacts.

Opening a 28 is painful -- welded heat stacks need drilling and replacing.


Pauli

[Geoff Quickfall]

Agree with Paul!

Try deoxit and some mechanical cleaning with a stiff artist brush that fits into the battery compartment.

Work the brush into the compartment first, shake any debris out, repeat many times. Then introduce a drop deoxit onto a brush and paint the springs with it.

OR

try this :-)

Read the whole posting: Shucking the clam shell