Pentax Digital Spotmeter battery door stuck

[bomzi]

My trustly Pentax Digital Spotmeter has a jammed battery door.
I've taken out the two little screws but the compartment is not opening.

Does anyone have any suggestions on how to get this opened? I need to change the battery.

[pendennis]

The two small screws don't need to be removed.

The battery compartment cap is removed by using a nickel-sized coin, unscrewing it from the base. The batteries you need are 6v silver or alkaline cells. They look like 1/3 sized AA's. While you have the battery out, clean the contacts with a pencil eraser, both the positive and negative contacts.

[bomzi]

Well, the battery door is jammed. I've tried coins and screwdrivers to no avail.
So I tried to remove the entire compartment by removing the screws but that's not working either.

Might try and drill two small holes and use a golf shoe spike wrench to open it.

[Bob Salomon]

Well, the battery door is jammed. I've tried coins and screwdrivers to no avail.
So I tried to remove the entire compartment by removing the screws but that's not working either.

Might try and drill two small holes and use a golf shoe spike wrench to open it.
Let some white vinegar soak into the doors seems for a while. Or use lemon juice.

[pendennis]

Well, the battery door is jammed. I've tried coins and screwdrivers to no avail.
So I tried to remove the entire compartment by removing the screws but that's not working either.

Might try and drill two small holes and use a golf shoe spike wrench to open it.

That solution may very well destroy the screw cap. A spike wrench generates way too much torque.

Bob's suggestion is spot on. Use a cotton swab, and dab white vinegar around the cap, and allow it to penetrate. Try this several times, allowing about 30 minutes between applications. The vinegar will penetrate the threads, but it does take a while.

[Drew Wiley]

Well, you certainly don't want any vinegar seeping into the actual battery compartment. I'd swab it on with a Q-tip with the meter upright, and hope capillary action draws some in. There is a thicker product called Aluminum Jelly available from hardware stores. Test it on some unimportant corroded aluminum first,
so you know what to expect. Hopefully you won't find a corroded battery inside the meter as the source of your problem. That might require formal servicing if the contacts are conspicuously messed up too.