R.B Cycle Graphic question: How do I R. the B.?

[Leonard Robertson]

You may be able to poke the brass part (which shows through the oval hole in your pictures) with a fine knife blade or needle and rotate it to see if you can find a hole where the original pin was. Or the hole may be past the oval opening and not visible without moving the brass part toward the front of the body. I'm not sure how strong the spring is. The spring on the RB catch on my Cycle must be broken, as I can slide the catch back and forth and it stays in either position. But taking the two screws out will probably be the best bet.

Once you get your back to rotate, turn it 45 degrees and on the upper RH corner of the rear body you will see a round depression with a sliding metal catch recessed into it. Slide the catch toward the corner of the body and the revolving back will come off. It is removable so you can install the Cirkut Attachment after viewing and focusing with the RB in place.

Len

[Jim C.]

Thanks, that's the answer I need.

What threw me off is that there is no evidence of a former button wearing on the black painted brass plate on my camera.

Now all I gotta do is fix it.

I've come to believe that a lot of "painted" exterior camera parts might have been chemically blackened,
the tensioning control plates on the Graflex SLR I'm working on resisted my usual lacquer thinner scrub.

[Jim Jones]

There is no evidence of the back rotation lock pin on my RB Graphic ever having a head. There were some minor changes in these cameras over the 15 production years.

[Vincent Pidone]

I've come to believe that a lot of "painted" exterior camera parts might have been chemically blackened.....

I'm certain that you are right.

I wrote "paint" in order to avoid further muddying the waters before my original question was answered. It's definitely not paint.

Chemical patina, and it looks to be rather thick.

If the part is brass it might have been done with "liver of sulphur" (common patina for jewelry).

If the part is steel, it might just be "fire scale" (i.e. iron oxide caused by heating the part).

Anyway, I intend to remove the two screws and see if I can install a brass pin in the catch, if not, I might thread the hole and use a screw.

I'll post some pictures, but this is "back burner" stuff, so don't hold your collective breath.

And yes, Jim Jones and Jim C. have two different style pins in the slider. Mine will likely be a third kind.

Thank you all.

[Vincent Pidone]

OK, here it is with the cover off:



The camera back is on the left in the photo.

I can insert an xacto blade on the right side of the pin, which indicates that the pin doesn't go any further toward the front of the camera than you can see in the picture.

The pin won't turn (rotate) or slide easily, i.e. a gentle push with a scribe didn't move it.

Either the pressure from the back or the spring (which I can't see) or both, keeps it from moving.

Any ideas?

I don't see any access points inside or at the rear of the camera where I might otherwise get at this.

My sense is that this was not assembled through this window (which would have made repair easy) but from the inside.

I can try to cut a notch in the brass to gain some purchase for turning it, but would rather not if someone can come up with an alternative I've overlooked.

[Tracy Storer]

If the pin is all the way forward, the back SHOULD be free to rotate. Can you slip the blade into the gap also showing in your photo? If you can, you will either encounter the pin protruding, or you won't. If not, there is some other obstruction to rotation.

[Vincent Pidone]

Tracy,

The pin is all the way toward the back of the camera, i.e. fully engaged.

You can actually see that in the pictures that I posted if you look closely.

The pin is doing it's job of obstructing the rotation of the back (and quite nicely at that).

If this camera was a "beater" I could fix this in no time flat with any of several ugly kludges.

Unfortunately, it is in great original condition with the exception of the missing pin handle/button/whatever.

I also have a (I think) minor problem with the volute shutter, but that's for later.

[Jim C.]

Vincent, there looks like there's some 'gunge' on the locking pin, it might be just stuck and in need of some
more coaxing ( wiggling ) to free it self. I see something else in there on the right side, could be the spring
or a ball bearing, looks round.

A pair of good quality needle point tweezers like the kind to remove splinters could give you the grip you need
to slide it towards the front of the camera, there will be resistance because there's a spring in there
and it might also be gunged up. Once you can rotate the back you should be able to remove the pin to clean and size a new
lever for it.

[Tracy Storer]

If you're very careful, you could (on a drillpress, after removing the ground glass frame) drill a small clearance hole through the back to allow the pin to escape. Once getting everything apart, you could do a very clean repair of the hole.
Where are you located, by the way?

[Vincent Pidone]

Tracy,

I'm in Kingston, NY.

Again, because of the unusually good condition of this camera otherwise, I'm reluctant to take the rough and ready approach to fixing it.

Jim C.,

I'm sure that what's visible on the right of the brass is the spring that holds it in place to lock the back from rotating.

I'm kind of biding my time in deciding how to move this, somebody might still have the magic bullet.