Rangefinder Repair

Nikon D300, Micro Nikkor AF-D 105mm F.2.8

I had two fixer-upper projects sitting on the back-burner for a while that I’m happy to say I made progress on this weekend.

My Dad gave me a 1952 Canon IV-S rangefinder a while back which was in decent operating state except for having a hole burned into its shutter curtain.  This is a common affliction in Leicas and other classic rangefinders with cloth shutters, as the lens can easily act as a magnifying glass when sunlight shines directly into it.

Feeling a bit intimidated by the very old-school IV-S, I had purchased a 1963 Petri 7S off eBay at a bargain price (under $20) in order to ease my way into rangefinder shooting.  But despite the description reading “camera operates fine” I discovered the film advance lever was stuck.

I tackled the Petri first, having found a clue online to check the springs underneath the bottom plate.  However, the screws holding the plate on were stuck and wouldn’t budge at all.

I purchased a can of Kano Kroil “The Oil That Creeps” which is supposed to be better than the average penetrating oil, and it did the trick nicely.  After leaving a drop sitting on the upside-down screws for a minute I wiped them off and the screws came right out.

When I first received the 7S the shutter fired for me once, but then when I tried the lever it barely moved. It was somehow obstructed and I couldn’t advance or cock the shutter again.

With the bottom plate removed the problem was obvious:  the gear on the bottom of the advance “axle” had a peg which was hitting a small plate in the corner preventing it from rotating clockwise.

For a minute or so I puzzled through why the plate was stuck in the wrong place.  But then I literally hit on the right solution when I pushed the long arm located to its right towards the plate.

It was a temporary “stuckness” and the arm and plate moved a few millimeters to the left, freeing the advance gear and lever to… well, advance!  Perhaps I will need to grease some parts later, but I have cycled the shutter and advance many times since.

Emboldened by this feat of skill (er… ok, good luck) I proceeded to the Canon.  Looking in through the lens mount into its shutter crate it seemed pretty obvious to me where the light leak was coming from.

The left shutter (in place after an exposure) looked practically brand new.  But the right shutter (in place when cocked) had an obvious hole in addition to a previous patch attempt with black fabric paint by my Dad.

He had encouraged me to try patching it again when he gave me the camera, but I read on the above referenced Leica forum that Star Brite Liquid Electrical Tape was the way to go.

I gave the can a good shaking, opened it up, and then applied some over the hole and a few other places for good measure using a fine artist paint brush.  The shutter sat exposed on my desk overnight to ensure it was fully dried, and when I tried it just now it seemed to be working smoothly.

Well, I guess I have two more rangefinders to play with and test out.  I will report back on that later.