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Thereplicant07
Tinkerer
Username: Thereplicant07
Post Number: 1
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, March 19, 2011 - 01:33 pm: | 
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Hello, everyone.
I recently purchased a Minolta Hi-Matic 7s from eBay. The shutter was stuck and the focusing off. I fixed the shutter (someone had been in the shutter itself and springs & cogs weren't how they should be!)and ran a roll of film through it, setting shutter speed and aperture based on camera's EV rating. All pics were perfectly exposed so the meter was fine. Focusing was off, however, so I had to adjust the lens and rangefinder to infinity. In doing that one of the little screws for adjusting the rangefinder fell into the camera and I had to take off the whole front assembly to get to the screw.
Long story cut short, I got the screw, adjusted the rangefinder and all is well.........but now my meter isn't working right. The bar moves when I move the sensor over a strong light but it won't go over 9EV, even when pointing the camera towards the sun on a sunny day. Indoors the bar never gets above 6EV even when an inch away from a 100w bulb.
I've looked at the 2 red wires going from the meter to the sensor in the lens and they look ok. The blue wire from the battery to the meter is also in good shape too. I have tried 2 brand new MRB625 Weincell batteries so eliminated that. Since the bar is moving when the light changes I'm guessing it's nothing to do with a broken wire anywhere. My logic being a broken wire would mean the bar not moving at all when pointing at bright light.
Does anyone have any ideas what the problem could be? I've looked through the archives but most people are talking about corroded wires and meters that aren't working at all. Mine is.....just not very well!
I hope someone can help. Thanks in advance. |
Neuberger
Tinkerer
Username: Neuberger
Post Number: 44
Registered: 01-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 20, 2011 - 03:38 am: |
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Quite some time ago I was faced with what I consider a similar if not the same problem in two old Hi-Matics. In one case the needle swing was incomplete because it was blocked by a small screw had entered the meter housing and had been attracted by the magnet. After careful removal of that screw everything was fine again.
In the second meter the serrated black semi-circle plastic piece, usually glued to the back of the housing and part of the needle trap mechnism, had unstuck from the metal and made the whole thing freaky.
Dismantling the meter is possible, but not easy and reassembly can give you some pain in the ... you know where. Once misbent the retracting coil springs can NEVER be put right again, so do be careful inside the meter. |
Thereplicant07
Tinkerer
Username: Thereplicant07
Post Number: 2
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 20, 2011 - 07:36 am: |
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Thank you, Neuberger. This is the first camera I've ever opened up and while I managed to put a few cogs and springs back into the shutter system (after a little studying) I may be biting off more than I can chew opening up the meter. But then what have I to lose? If all else fails I'll just have to use a handheld meter, which is the situation I'm in now anyway.
I think I'll try and take some pics as I go along to aid me in the reassembly. Thank you, again, for the advice. |
Thereplicant07
Tinkerer
Username: Thereplicant07
Post Number: 3
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 27, 2011 - 09:45 am: |
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As an update I've checked out the meter. Nothing is stopping the meter's arm from moving and I see no obstructions. The semi-circle piece with the grooves in, which steadies the exposure meter when pressing down the shutter, is securely in place.
I'm at a loss as to why it's suddenly stopped.
I have purchased another Minolta Hi-Matic 7s from Ebay for £1. The shutter mechanism is broken and aperture blades stuck, as well as a broken self-timer. Supposedly the meter on it is working correctly so I was thinking of transferring the meter over to the Hi-Matic 7s I have now.
Does anyone know if this is a hard job to do? Anything I have to watch out for?
Thanks again. |
Paolo_bonello
Tinkerer
Username: Paolo_bonello
Post Number: 5
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 27, 2011 - 10:29 pm: |
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I'm in a similar situation. My meter is dead on a pristine looking black 7s. The wires conduct from the battery box but I do not know if the cell on the front of the lens is working to its full potential. I have acquired another much cheaper 7s to pillage for the meter and beam splitter glass which was blemished by an agressive cleaning job done by someone prior to me owning the camera. Am looking for instructions on dissassembly and reassembly of these systems. I can get a little movement from the needle if I hold the camera with the lens pointing directly downward into an intense light source. I'm guessing that simply alleviates some of the counterbalance weight on the needle so it is much easier to move and hence I can get a slight meter reading. |
Thereplicant07
Tinkerer
Username: Thereplicant07
Post Number: 6
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, March 28, 2011 - 10:50 am: |
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I'm getting a little more needle movement than you, Paulo, and don't have to tip the camera downwards or any other direction.
My needle just won't go over about 11ev, even when pointing directly at the sun. Indoor lighting doesn't move the needle above 5.7ev at all unless it's an inch away from a light bulb where I get between 7 and 9ev.
Using a precision screwdriver on the counterweight arm I can move the needle all the way past 17ev freely. The sensor in the front of the lens isn't blocked and the small shutter moves across as it should when I turn the meter from the 'off' position on the iso dial.
My other 7s has a meter that's working fine. Just don't know if it's really hard to replace. There's plenty online about adjusting rangefinders, removing the lens board and even delving into the shutter mechanism, but nothing about the meters.
Hmmmm.... |
Milosdevino
Tinkerer
Username: Milosdevino
Post Number: 18
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, March 29, 2011 - 03:18 am: |
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The only other things I can think of are:
1)One of the soldered joints in the wires became weakened somehow and is causing a resistance.
2)The small shutter in front of the light sensor has become mis aligned and is blocking more light than it should.
If none of that works,I would consider swapping the working lens assembly onto the other camera with the working meter. At least you know that each of these seperate assemblies works. It might be easier than trying to remove and replace the meter.
Good luck, let us know how you get on. |
Thereplicant07
Tinkerer
Username: Thereplicant07
Post Number: 7
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 30, 2011 - 07:10 am: |
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Update: The metal cover that slides over the sensor when you select the iso setting was loose. It was working about 50% of the time but occasionally didn't move when I selected a different iso. I've now, with the help of two drops of superglue, fixed it and it runs as it should.
My ev needle does now move a little more freely and an inch away from a 40 watt bulb it goes up to around 12ev. Compared to my other Hi-Matic 7s, with the working meter, it's about 1-2ev lower in all lighting conditions. My guess was, as I found you thought too, is there's resistance somewhere from bad wire or weak solder.
I've ordered some 10/0.1 equipment wire and will replace and resolder throughout the camera to see if that solves the issue. Hopefully it will because the other Hi-Matic 7s, with the working meter, had a stuck shutter, and stuck aperture blades. Someone had been in the shutter mechanism itself and not put things back the way they should. Get this: you know the small plastic washer in the bottom plate that goes round the thread for the tripod fixing? That was inside the shutter mechanism. And the little metal piece that sits on the self-timer arm was rattling round inside the bottom plate!
Anyway, with lots of cleaning oil off the shutter blades and putting cogs and springs back where they should the shutter is working (though a little more oil needs to be wiped clean but it's coming from all over). The aperture blades were stuck at f1.8 because it gets kinda stiff there and the long spring that pulls back the aperture blades wasn't strong enough. I took the spring off on end, hooked the spring back on about half way down it and hooked the end back over on the opposing hook. I doubled up the spring, if you know what I mean. Well, the aperture blades now open and close as they should too. Only thing left is that the arm that moves the aperture blades is bent so it's not catching on the notches on the top plate. So when selecting the aperture I'm not getting distinguished click, click, click sounds and it's pretty loose. If I can bend the arm back a little I should have 2 working Hi-Matic 7s's. |
Thereplicant07
Tinkerer
Username: Thereplicant07
Post Number: 8
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, April 03, 2011 - 11:47 am: |
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Final summary:
I replaced the wire from the meter to the sensor and still the meter either doesn't work or is 2-3 stops off my gossen lunasix and other h-matic 7s with working meter. I just took the lens assembly from the first 7s and put it on to the body of the second 7s because the 2nd 7s had a stiff focus ring, no self-timer but body was in better condition and the meter worked.
So now I have a full working Hi-Matic 7s in very good condition and one that works but no meter, no self-timer and focusing is pretty stiff.
Thank you to everyone that tried to help. I appreciated it greatly and learnt a lot. |
