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Author Topic: Spotmatic battery cover - how to unfreeze?  (Read 2655 times)
Scott
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« on: August 26, 2006, 11:01:01 AM »

Hi, all -

Well, just got back from the beach, and my new (to me) $10 Spotmatic is here.  Camera seems alright, 'cept the battery cover is frozen in place.  I'm guessing this is indicative of some compartmental corrosion.  Any ideas on how to open the thing?  The slot for unscrewing is shallow enough that it seems like it'd be easy to chew up.  I'm guessing some vinegar or water or something drizzled onto the edge of the cover might help.

Anyone have experience with this?

Thanks,
Scott
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Glenn Thoreson
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« Reply #1 on: August 26, 2006, 12:03:47 PM »

I think your idea with the vinegar is a good place to start. You may want to form a little dam around it with some putty or something, soit will hold a liittle pool. Rapping on it once in a while as it soaks would help, too. On the other hand, it might just be really tight. If you do scar it, I see them listed all the time on the auction thingy. The down side is, it would cost as much as the camera did.
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Scott
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« Reply #2 on: August 26, 2006, 12:41:20 PM »

Success!  I mounted the body in one of my woodworking vises upside-down, pooled up some vinegar with a pipette (surface tension kept it in place nicely), and waited about twenty minutes.  The compartment actually has almost no corrosion, and had an Energizer 387S silver oxide battery in it, so I know what I'm shopping for now.

Woo hoo!  Thanks, Glenn.  The $7 bellows also arrived (as did the $5 reversing ring).  Get started on macro shooting this week!

Scott
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Raid Amin
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« Reply #3 on: August 26, 2006, 12:41:38 PM »

I paid $50 for my Spotmatic with a 55mm lens,and now it looks so expensive compared to your camera!

Raid
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Scott
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« Reply #4 on: August 26, 2006, 12:55:56 PM »

Actually, Raid, I think we got the same camera - Honeywell Spotmatic with the 55/1.8, right?  Mine has a nice dent in the prism, which has no effect on anything, but I think that and the stuck battery cover scared everyone off.  Yours is in much nicer physical shape from the pictures you posted.

We'll see how they stack up after I locate a new battery here tomorrow.  Is yours getting a CLA, or was that a different camera?

Scott

Quote from: Raid Amin;49527
I paid $50 for my Spotmatic with a 55mm lens,and now it looks so expensive compared to your camera!

Raid
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ImageMaker
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« Reply #5 on: August 26, 2006, 01:40:59 PM »

Scott, you don't have to spend the money for silver oxide for that camera; my Spotmatic works fine with the 10/$1 LR44 alkalines I get at the local dollar store.  Assuming that 387S is the same size (and they do also have a smaller size alkaline button cell at the same price), a dollar's worth of those cells should keep you shooting for 10-15 years...
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Scott
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« Reply #6 on: August 26, 2006, 02:55:11 PM »

Well, the LR44 didn't work.  Too tall.  Back to the drawing board.  Might be heading to Radio Shack tomorrow to see if they have a match...

Quote from: ImageMaker;49536
Scott, you don't have to spend the money for silver oxide for that camera; my Spotmatic works fine with the 10/$1 LR44 alkalines I get at the local dollar store.  Assuming that 387S is the same size (and they do also have a smaller size alkaline button cell at the same price), a dollar's worth of those cells should keep you shooting for 10-15 years...
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Kevin Roach
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« Reply #7 on: August 26, 2006, 04:19:25 PM »

I got a slip-on accessory shoe for my spotmatic. Covers up that ding in the prism. I wonder what is with these cameras, always falling on their heads.
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Dean Williams
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« Reply #8 on: August 26, 2006, 06:40:33 PM »

Scott, go to a drug store (or Radio Shack) and get a pack of #312 hearing aid batteries.  Then find a small O-ring that will fit around the circumference, to keep the battery from sliding around inside the compartment.  You can get O-rings from an auto parts store, like NAPA.  The batteries come in a pack of eight for a few bucks.

Just for reference, since Scott has his battery cover problem solved;
If you have a stuck cover, and need to soak it in something like vinegar, you can remove the bottom plate from the Pentax Spotmatic types by just removing a few screws.  The only thing loose in there is the rewind button, (on some of the model variations).  No springs or things like that will fly out.
Then you can soak the thing in vinegar without worrying about getting it into the camera works.  

The entire battery compartment comes out this way, and if needed you can then clean the battery contact inside the camera too.
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Dean W
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« Reply #9 on: August 26, 2006, 06:51:55 PM »

On one Spotmatic I used to own, the previous owner had drilled two small holes at the end of the knotch where a coin would be used to turn the cover.

It then would be possilbe to use a double prong tool to open the cover.

It  worked great, the previous owner must have really had a cover that was stuck.  Just an idea for someone who has problems in the future.  I never tried drilling holes so don't know how dangerous it would be for the camera.  Possibly he/she took the bottom plate off the camera to do it.

Leo
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L Christoffer
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« Reply #10 on: August 26, 2006, 08:04:45 PM »

You could try the method that a local pawn shop tried a few years ago. After informing them that the nice Spotmatic they had for sale had a stuck battery cover, they offered to help get it off. Well, I looked around the little shop while they tried their hand at the stubborn cover. A few minutes later, I looked over and saw them using a huge screwdriver to twist, turn, and pry it off the camera. Luckily, in a testament to Pentax durability, the camera body itself survived, but the cover was destroyed. Needless to say, the pawn shop closed down about a year later, and all contents were sold at auction.
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LarryD
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« Reply #11 on: August 27, 2006, 04:58:55 AM »

Those 2 small holes may also have been because he was using Wein cells or Hearing aid batteries. it allows in air because what is inside the compartment is not enough for some cameras.

Larry
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Scott
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« Reply #12 on: August 27, 2006, 05:24:11 AM »

Thanks for the input, Dean.  Good to know for future use.

Ok, battery snafu: Here're some pictures of the camera:





Inside the battery compartment is a little conical gasket-type thing that lifts the battery up from the bottom of the well slightly.  Looks original.  Keeps me from using the LR44/A76 batteries that Donald was suggesting.  The 387S is a perfect fit with its little plastic ring; anyone know if the 312 is the same size as the 387 without the ring?  If it's any taller, it won't fit.  If I need to go chase down a 387, that's fine.  If the 312s'll work, that'd be easier, but I'll soon be spending as much on batteries as on the camera.

Help!

Ok, general question - anyone know how to identify model on this camera?  Is it a Spomatic, a II, SP, etc?  I'm new to Pentax...

Thanks for all the help, guys.
Scott

Quote from: Dean Williams;49592
Scott, go to a drug store (or Radio Shack) and get a pack of #312 hearing aid batteries.  Then find a small O-ring that will fit around the circumference, to keep the battery from sliding around inside the compartment.  You can get O-rings from an auto parts store, like NAPA.  The batteries come in a pack of eight for a few bucks.

Just for reference, since Scott has his battery cover problem solved;
If you have a stuck cover, and need to soak it in something like vinegar, you can remove the bottom plate from the Pentax Spotmatic types by just removing a few screws.  The only thing loose in there is the rewind button, (on some of the model variations).  No springs or things like that will fly out.
Then you can soak the thing in vinegar without worrying about getting it into the camera works.  

The entire battery compartment comes out this way, and if needed you can then clean the battery contact inside the camera too.
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connealy
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« Reply #13 on: August 27, 2006, 08:13:04 AM »

Quote from: Scott;49632
...Ok, general question - anyone know how to identify model on this camera?  Is it a Spomatic, a II, SP, etc?  I'm new to Pentax...
I believe "Spotmatic" is the correct model identification.

The Pentax USA web site has downloadable manuals in PDF format for virtually every Pentax product inlcuding all the Spotmatics.  If you download the one labelled only as "Spotmatic", you will see that it is the same model as yours, marketed in the U.S. by Honeywell.

I don't think the battery voltage is critical.  I presently have a tiny hearing aid battery in mine with an o-ring to make it fit.
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ImageMaker
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« Reply #14 on: August 27, 2006, 08:14:54 AM »

Quote from: Scott;49632
Inside the battery compartment is a little conical gasket-type thing that lifts the battery up from the bottom of the well slightly.  Looks original.  Keeps me from using the LR44/A76 batteries that Donald was suggesting.  The 387S is a perfect fit with its little plastic ring; anyone know if the 312 is the same size as the 387 without the ring?  If it's any taller, it won't fit.  If I need to go chase down a 387, that's fine.  If the 312s'll work, that'd be easier, but I'll soon be spending as much on batteries as on the camera.

Help!

Ok, general question - anyone know how to identify model on this camera?  Is it a Spomatic, a II, SP, etc?  I'm new to Pentax...


That's the bad news with Pentax -- they were amazingly good about not obsoleting old lenses (until the K mount, and even then they made an adapter to use M42 lenses on the K cameras), but they changed the battery compartment every model run or so.

I'd start by taking off the bottom plate and making really sure that insert isn't just stuck in.  Failing that, any cell that fits will work; the Spotmatic family and early K models (all the ones that used stop-down metering, anyway) used a bridge meter circuit that centers the needle by matching resistance of the meter cell network against that selected by the film/shutter speed dial, and the centering is completely independent of voltage -- use a higher voltage cell, you get more travel from center, but the center will still happen at the correct light level.  That means any mercury, zinc-air, alkaline, silver, or for that matter 1.5 V lithium cell will work fine; all that's necessary is that the voltage not be high enough to drive too much current and damage the meter cells or galvanometer (and anything between about 1.0 and 2.0 V should be okay in that regard).

If the insert is in fact part of the battery compartment, it should come off with the bottom plate, and if you really want to be able to use the (much easier to find) LR44/S76 equivalent cells, you could try to find a replacement bottom plate with the correct compartment, though it's probably easier to just take the camera to Radio Shack and fish for a cell that fits the compartment you have.

For identification, most Spotmatics I've seen have the model designation on the top plate beside the rewind crank.  Mine has SP and the serial number there.  I can see *something* engraved or stamped there on your camera (front view), but can't read it in the photo.  If there's only a number, no letters, then you'd have an original Spotmatic.  There were also, AFAIK, SP, SP2, SP1000, SP500 (the latter two identical except for lack of a mark for the still-present 1/1000 shutter speed), and then the wide-open meter models, F and a couple others (EF and EM?), which require special lenses to do their wide-open metering trick and *might* have a different meter circuit that is voltage dependent -- I'm not certain, never handled one.  Might well be other versions I don't recall offhand.
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