I just got a bunch of M42's

[kshapero]

The battery compartment cover is probably corroded shut from a leaky battery.
Remove the four tiny screws and the entire bottom cover can be taken off.
Be careful cleaning up the corrosion; any amount of mercury can't be good for you.
I have it on very good authority that you should *NEVER* use vinegar.

Rather than look for an adapter, I suggest you try using those Takumar
lenses with that Spotmatic II. It's a wonderful camera.
And if you'd like to get it working like new, send it to Eric Hendrickson
pentaxrepairs@aol.com

Chris

Ok I took off the bottom plate, but I still can't open the battery cover. Any ideas?

 

[ZeissFan]

If you get an M42 to K-mount adapter, make sure it allows for infinity focus. Some of the cheaper ones won't allow the M42 lens to focus to infinity.

 

[kshapero]

Can you use vinegar or wd 40 to loosen?

 

[wolves3012]

Ok I took off the bottom plate, but I still can't open the battery cover. Any ideas?

Soak it in penetrating oil for a week, at least. Then also apply some heat from a hairdryer and try again. Try to apply the heat around the battery cover more than on the cover itself if possible. Patience, rather than brute force, is the key. If it still won't shift. soak it again and wait. Regarding the mercury hazard, try and do it in a well-ventilated area and don't breathe any fumes from heating it.

By the way, I used to have a Spotmatic, they're excellent cameras. Only niggle is the stop-down metering, where the view goes very dim suddenly! Something you may not have to suffer if you can't fix the meter up...

 

[peterm1]

I would try WD-40 or something of that sort. But if perchance you find it impossible to get the cover off, remember that (a) the Spotmatic works perfectly well without a meter and (2) in the alternative you can pick up a new Spotmatic body dirt cheap on eBay.

 

[tedwhite]

Or a new bottom plate. My suggestion: Just send it to Eric Hendrickson. He's the retired head of the Pentax repair division.

As others have said, Pentax lenses are simply superb.

Ted

 

[ZeissFan]

If you're going to use WD40 or some type of penetrating oil, spray it into a small plastic cup and NEVER directly onto the camera. Then use a cotton swab to get it into the crevices. But don't overdo it.

 

[kshapero]

Well I soaked the bottom plate with stuck battery cover over night in vinegar. battery cover came off smooth as silk. No real corrision I could see but a definite dead battery.