Sears KS-2/Ricoh XR-7 repair
This is a very specific question regarding a light-leak in a Sears KS-2/Ricoh XR-7, and I presently have a working solution - I just want to make it better.
A light seal is needed on the sides of the back. There was also a seal in the top and bottom channels, but it does look more like a light-trap. Does anyone know if this is a sufficient baffle without any seal? This "channel" is on the camera, and the lip on the back goes into it.
At the moment I have wool yarn in the top and bottom channels, and it works fine; but it does make the back a bit tough to latch shut. The original seals were foam, and had degraded. I know I can get new (and better) foam online, but wonder if it is necessary for the channels. I made a felt seal for the ends of the back and they are fine too, without providing any resistance to closing the back.
To reiterate, it is now light-tight, but the felt in the channels create resistance when latching the back.
This is my maternal Grandfather's Sears KS-2. The shutter had jammed, it had a light leak, and the plastic "cap" on the rewind crank had broken. It was "repaired" by a camera chain here in Cleveland, Ohio. After three tries they didn't get it right.
I became quite angry and decided I could also not repair it in three tries.
I was wrong. I fixed it the first time.
As it turns out, the old foam light seals had degraded (thus the leak) and it takes only a small bit of the sticky material to get on the shutter and make it jam.
Since the problems had persisted, I'm not sure if the shop replaced the shutter as they claimed. Their swapping of the back did not improve the light leak; the replacement back also had barely any foam seal left.
I cleaned everything I could without dissembling the camera, and used felt and yarn to recreate the light seals. It has been fine in the 2.5 years since I did this myself.
They also replaced the broken plastic "cap" on the rewind crank with the wrong one. It looks similar, but holds the shaft 1/8 of an inch too high. This often causes rewind problems; you think it's rewound because it stops engaging the film cartridge, open the back, and expose some film. I have that fixed now as well.
Due to my frustration at the time, I spent a lot of time online. I now have a repair manual (that does not address whether the seals in the channels are necessary), and a box of cameras with compatible parts. I will use one someday to learn how to completely disassemble and clean it before attempting a thorough rebuild on my Grandfather's camera. It works fine now, but some day I should clean it well.
Check on E-bay for a light seal kit. I bought some for several Petax K1000's, Minolta SRT's, and Yashica's. I'm sure that even if a specific kit is not listed you could use one meant for another camera or buy the material and cut it down.
The channels do need the foam or yarn to seal. Either jon goodman(hangs out here) or even a piece of foam from the craft store. They're about 8X11" and less than $2.
Heavily sedated for your protection.
I've used the craft store foam for years and it does a great job, but the stuff isn't the same springiness as real light seal foam. It's much stiffer and less compactable so it will likely be worse than yarn as far as making the back harder to close. I recently bought some real stuff from Micro Tools and it's quite nice but also pretty pricey. It's perfect for restoring priceless classics or sentimental old favorites.
In life you only get one great dog, one great car, and one great woman. Pet the dog. Drive the car. Make love to the woman. Don't mix them up.
Truzi, my advice to you is to use yarn but yarn of a narrower gauge. While I am at it, I never snap shut backs on SLRs because doing this over and over again grinds the latch so that there eventually becomes a bit of 'play' that can cause light leaks. Do this, instead: Pull out the rewind crank fully and while you are holding this open, with your other hand (thumb on back and index finger on front of body) firmly press the back to the body. Only then do you release the rewind crank. This way there is no grinding of that rather delicate (and too fragile, in my estimation) latch. - David Lyga
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
I'd not thought of using thinner yarn. As it was, I had to twist it to get a thickness that would fit.
The reason I'd originally asked the question is that the top and bottom channels _look_ like traps, and the leak was only on the end of the camera (where the take-up spool is). The only reason I noticed it was leaking was I shot a few rolls without putting the case back on after loading; the leather case covers the joints between the body and the back.
@David Lyga - My grandfather used to close the back they way you mention, even when the camera was new. He was very patient and methodical with any mechanical device. I've tried to adopt those habits, but it is difficult.