Adjusting the RF in a Karat 36

[titrisol]

I followed the C.Sherlock videos to get this camera back to life.

However when I put the top together I needed to readjust the RF.
The RF unit was taken out to clean and lubricate the film transport/winding mechanism and is held by 3 screws (marked in yellow)

Under the top of Karat 36v3 RF unit out

I looked at the unit and it was focused at infinity by default, and has a small pin/tab at the bottom that moves one of the sided for close focusing, and a spring returns it to infinity. Mine was sluggish to return and I cleaned the rail with a qtip moist in electrical contact cleaner (green Agfa goo).

Under the top of Karat 36v3 RF unit

Bottom of RF unit

When focusing a lever moves and pushes the pin, so after assembling I left the screws loose, and moved the RF unit horizontally (L-R) I got infinity right. Confirmed with 2m(6ft) and 5m(15ft) looking at a bookcase.

[melek]

Thanks for posting this. I just brought my Karat 36 up from the basement with the intent of working on it, including the rangefinder.

I've found some of the Agfa rangefinder units to be average, and adjusting them to be a finicky process that might hold - or might not.

[titrisol]

I didn't touch the unit itself, it was self contained
I looked through it and it was well focused to infinity, so that was a win
Then I tried to figure out how it worked and how it coupled, and from there it was clear that this adjustment wasn't too bad.
Alex gave me some pointers on how to clean the mechanism, and suggested to lubricate it with graphite
I was thinking on using a drop of blue threadlock in those holding screws but the amount of force exerted by the RF coupling is minimal

If this was out of whack I think you can adjust infinity by the screw on top of the one marked with the yellow +
Vertical adjustment would be a bear though

IN the next Karat I opened I marked the location of the RF unit with a sharpie to make reassembly easier. (ghetto way)

[P C Headland]

Chris's videos are excellent. They gave me the confidence to fix several cameras recently.