Cleaning Light Seal Channels

Not a Canon guy but on Nikons of that vintage, the edges of the film door formed a light-tight baffle with the channels in the body. The seals along the length of the door were more about moisture and dust protection. Never replaced them with no light leak issues. The seal that does matter is usually at the door hinge.

If you still want to use the seals, I've had luck using isopropyl alcohol as a solvent. Whittle some popsicle stix or narrow splints of wood into a narrow chisel shape to scrape out the goo. A good pre-op precaution: make sure to cover the shutter with some taped-down thin cardboard or index card. Sticky old seal material invariably lands on unprotected shutters.

As above.

Alcohol, cocktail sticks, wooden skewers, cotton buds, other bits of wood shaped to fit.

I like the bamboo satay skewers, with a pointed end and a larger, flat 'grip' end, can be adapted to a variety of useful shapes.

Bamboo skewers make good 'chisels' when trimmed down.

A tip for softening the old seals before scraping them out is to get strips of facial tissue and twist them into thin ropes which can then be pressed down into the door channels and then drip your solvent of choice onto the tissue. This prevents solvent from flowing all over the place and the tissue wicks the solvent onto the rotted seals. May have to apply solvent several times to the tissue rope and tamp the rope down with your bamboo chisel. When the tissue is removed the old seal should scrape out easily. Finish off with cotton buds or bits of tissue on cocktail sticks. I have used both isopropyl alcohol and naptha successfully. Think I prefer Isopropyl.

I have a set of light seals for a friend's A-1. The online instructions warn that all residue must be removed from the channels or the new seals won't adhere to them. What sort of cleaning solution works best for this?

I have done what others have suggested above (but used Naphtha, not alcohol).

For light seals, I use black wool yarn, both in the channels and also along the door hinge. Never had a light leak.

Good luck.

For light seals, I use black wool yarn, both in the channels and also along the door hinge. Never had a light leak.

Yes! I too use wool / yarn for the door channels, although I use black sticky back felt for the hinge seal (and the mirror bumper).

Actually I NEVER bother to clean out the old foam from the channels, I don't think it's at all necessary. I just scrape out any dirt, bits of film etc. Then I spread in a thin layer of silicone glue and stretch the wool into the grooves, trimming and tucking it in it carefully at the ends and on either side of the film counter reset lever. I moisten both sides to prevent them sticking, then close the back firmly for a couple of hours. I find that the wool is pressed snugly into the grooves on top of what is left of the old foam, which you never see again.

I've used this method with perhaps over 100 SLR's and rangefinders, both for my own use, and to sell. I've never had light leaks or reports of them from buyers, or any other problems.

John,

Where do you get the black sticky felt from? And what specific one do you use? I have read about this in many online resources and would like to try it out.

Does the felt have good spring action to function as a damper for the mirror slap?

Thanks.

It's sold by art & craft suppliers, an A4 sheet lasts for ages. I just Google something like "Sticky back black felt" or "self adhesive felt sheet". Perhaps terminology in other parts of the World is different. Here's one UK result --- LINK --- Black Self-Adhesive Felt Sheet A4 | Hobbycraft

(I have no interest in this seller).

I think the springiness is just about OK to use it for the mirror bumper, often the foam replacement bumpers are too hard in my experience. The only problem is that the fibres of the felt can be a little untidy and visible in the finder. It's not really a problem as when the mirror flips up, it pushes any possible stray fibres out of the way of the light path and the image can't be affected. Again I've used it loads of times with no problems encountered.

It's sold by art & craft suppliers, an A4 sheet lasts for ages. I just Google something like "Sticky back black felt" or "self adhesive felt sheet". Perhaps terminology in other parts of the World is different. Here's one UK result --- LINK --- Black Self-Adhesive Felt Sheet A4 | Hobbycraft

 

(I have no interest in this seller).

 

I think the springiness is just about OK to use it for the mirror bumper, often the foam replacement bumpers are too hard in my experience. The only problem is that the fibres of the felt can be a little untidy and visible in the finder. It's not really a problem as when the mirror flips up, it pushes any possible stray fibres out of the way of the light path and the image can't be affected. Again I've used it loads of times with no problems encountered.

Thank you. This is wonderful information to me.