Stuck HP-65 Battery Cover

[Craig Bladow]

What is the best, non-destructive, method to remove the HP-65 battery cover? One latch will open but I don’t want to break the second latch, which is not budging.

[rprosperi]

(12-04-2017 11:29 PM)Craig Bladow Wrote:  What is the best, non-destructive, method to remove the HP-65 battery cover? One latch will open but I don’t want to break the second latch, which is not budging.

Assuming an original design HP battery, the only thing that would prevent that from sliding would be battery leak sludge. Is it possible the batteries leaked and the gunk has dried? If using a 3rd-party battery, I guess it's possible it shifted inside - if so, don't try this, it won't help.

If you think it might be the dried gunk, you could try dripping some vinegar between the cracks (acts as solvent to the dried acid - be carfeful not to use so much that it runs into the machine interior), and tilt the machine to get the vinegar to run over the latch path; let it sit a few minutes, and then firmly press it towards the center, it should move.

Be prepared for a mess - e.g. open it over some spread out newspaper or paper towels as there is surely a fair amount of gunk. And try to keep the wet gunk off your hands, it is acid after all.

[Craig Bladow]

As there was no sign of battery leakage, I applied a little more force with a spudger and got the latch to release. No battery leakage but an aftermarket battery that was preventing the cover from opening.

[Roman L]

This is an old post but I had the same problem and the solution was to loosen the top screws after removing the caps on the underside of the calculator. This allows to pry apart the shells by a few millimeters. This is sufficient to move the sliders to open position.