Mirror foam replacement with light shield in the way

[sevesteen]

I've got a couple of cameras that desperately need new mirror foam, but they have a shield in the way--like this Yashica J-5


Is there some better way of getting to this area without major disassembly?  

[philbirch]

I'd unscrew the two screws and take the front off, it will probably come with it. Not what I'd call major disassembly

[Stephen]

I think the two scews release the front cover, there may be a third underneath the bottom edge, the cover should lift away and reveal the screws that support the lens mount. Normally they are on segments of a flange around the outside of the mount, 4 screws at least.

See if the plate you want to remove is accessable without rmoving the lens mount, but I suspect that will be required.
Slacken each scew it turn, then remove in turn, and carefully remove the mount, noteing any washers or shims under each flange, they must go back to maintain accurate infinity focus.

At this point whatever they have used to retain the plate should be obvious, my guess is two machine screws into the chassis.

You may be able to bend the plate forward enough to get the foam in without removal of the plate.
The best glue is an impact adhesive, a thin coat on the chassis, and a thin coat on the foam, and allow to dry, then fitted into place. Use a minimum of glue. The foam density is not critical, and in some cameras can be replaced with soft cord of similar thickness, or a roll of silk tape.

Reverse assemble, and check via the viewfinder that the infinity focus is normal.

Stephen.

[sevesteen]

I already tried removing the screws to the cover plate--that lets it wiggle a tiny bit but it is still held on by the lens mount, without enough slack to get at anything underneath. No visible screws on the mount. My next step on my own would be to take the bottom plate off...but the door release lever on the bottom has a nonstandard screw--2 slots about half a mm wide, about 1mm deep on the outer edge, takes a spanner I don't have and don't know where to get.

But my actual question has been answered, even if it isn't the answer I wanted--there doesn't appear to be a generic way to replace the foam like this without disassembly.

[Stephen]

It may well be either the bottom Plate or the top that is holding things down, no way of knowing. I will ask a friend who serviced cameras and see what he says for Yashica. Later models have screws through the lens mount front surface.
Stephen.

[sevesteen]

I've also got a Penta J with similar issues, plus a loose mirror, plus a bad shutter plus someone else's obvious repair attempt where they've damaged the leatherette. Since it isn't a precious gem and I can't really make it worse I decided to try on it first.

It appears that to get the shield off you have to peel the leatherette and remove the snout or whatever the part between the lens mount and the main body is called. 4 screws under the front leatherette. I had already taken both covers off before I peeled the leatherette, didn't need to take the bottom cover and probably didn't need to take the top. I'm not yet comfortable on peeling the leatherette back on a camera that's mostly for display, so replacing the foam on the J-5 will have to wait.

...and after fixing the loose mirror I found the cause of the shutter issue on the Penta J, the bottom tape on the leading curtain isn't attached to the shaft like the top is. That's more than I'm willing to fix for the sake of this camera, although someday I may attempt it for the sake of knowing how.

[philbirch]

All part of the learning curve. Peeling back leatherette isnt so bad as long as you don't rip it. Take your time and drip a tiny drop of paintbrush cleaner into the fold-up and it will soften the glue making it easier to pull up. You can glue it back down using basic contact adhesive. I've done it dozens of times.