Leica IIIf - Repairing Light Leak from Top Plate Seam

[mgilbuena]

I have a Leica IIIf and experience light leaks that run through the sprockets when the body is exposed to bright light.

I reached out to Youxin Ye in 2013 regarding probable causes, and he replied:

IIIf light leak mostly come from the seams between the shell and top plate. You need to use paint stick to seal the seams.

The leak is not from the curtain and light shield. All post war screw mount bodies have this problem from time to time. As long as you seal all the seams, it will be good.

Today, I began preparing for a photography event and I realized I never addressed repairing this camera. I located a disassembly walkthrough at this site: http://tunnel13.com/blog/leica-iiia-cla-and-repair/ and I believe I can disassemble and reassemble the camera.

My question: Youxin refers to using a paint stick. Is this the same as liquid electrical tape, or is there a specific paint that is best for ensuring light-tight top plate seams? I assume the painting needs to be done with the top plate off, then put back into place as the paint is drying?

I haven't reached back out to Youxin, as the conversation was nearly 4 years ago.

 

[02Pilot]

I suspect what he's referring to is a waxy solid substance rather than liquid electrical tape. A substantial layer rubbed along the interface between the top plate and the chassis it should conform to the gap without adhering or migrating.

 

[mgilbuena]

For those of you who may be looking at this thread in the future, I've discovered what Youxin was referring to. He's very responsive!!

http://www.ebay.com/itm/37164963436...49&var=640636351039&ssPageName=STRK:MEBIDX:IT

"ART PRIMO - HOBO MARKER - SOLIDIFIED PAINT STICK MARKER"

 

[charjohncarter]

I haven't had this problem and I've had my IIIf for 52 years. So many thanks for the heads up and the paint stick information. Does he mean you do not have remove the top plate?

 

[Steve M.]

Looks more like pin holes in the shutter to me.

If you want to rule out the body, tape up the top and bottom plates where they meet the camera and run another roll through it.

 

[mgilbuena]

The light leaks began shortly after curtain replacement by Youxin Ye.

After opening the body, I immediately spotted the culprit: The felt strip (42-700.01-665 in the diagram below) that runs along the cover plate was pulled back, therefore not covering the gap between the cover plate and the slow speed dial.

The light pattern on the negatives (including the sprockets) indicates entry through the slow speed dial and onto the the film wound around the take-up spool.

I used page 51 from the Leica IIIf repair manual to go through the light-sealing for this model:

 

[Dwig]

For those of you who may be looking at this thread in the future, I've discovered what Youxin was referring to. He's very responsive!!

http://www.ebay.com/itm/37164963436...49&var=640636351039&ssPageName=STRK:MEBIDX:IT

"ART PRIMO - HOBO MARKER - SOLIDIFIED PAINT STICK MARKER"

In the appropriate colors, these are excellent for restoring engraved markings on lenses and bodies. They last nearly forever. I have a white one that I've used off and on over the last 30+ years.

 

[rick oleson]

I'll bet they look really cool in that shade of pink.

🙂 =

 

[mgilbuena]

In the appropriate colors, these are excellent for restoring engraved markings on lenses and bodies. They last nearly forever. I have a white one that I've used off and on over the last 30+ years.

Thanks for the suggestion! I touched up a Summitar and the IIIf top plate with fantastic results.