Calumet CC400 Rear Standard Lockdown

[Vlad Soare]

Hi, guys,

I've been wanting to get into large format for some time, and now I've finally bit the bullet and got a Calumet CC-400 in very good shape. Except for one thing, it seems to work just fine. The bellows look like new, there are no light leaks, all movements work nicely and smoothly.
Unfortunately, the rear standard cannot be locked in place. Even when the lockup knob is screwed in all the way, the standard still moves freely on the rail. Not even the slightest change in tension can be felt with or without turning the lockup knob. Unlike the front knob, which needs just a little movement to lock the standard and thus cannot be fully screwed in, the rear knob goes in all the way.

I removed the arced plate, the wheel and the lockup knob to see if I can do something about it. I must confess that I can't for the life of me understand how it's supposed to work. The knob screws into a hole. Looking down that hole I can see the rail and its groove, and I don't understand how the lockup knob could actually lock anything by simply going down into that empty space.
Is there anything missing? Should there be a metal ring or something that the knob should press against the rail?

Thank you.

[Will Thompson]

You are missing the metal insert and the nylon pressure bearing!

[Vlad Soare]

How do they look like, and how are they supposed to work?
Can they be improvised from something readily available from a hardware store? I doubt I'll ever find a Calumet nylon bearing for sale... :(

[Will Thompson]

Post a photo of the lockup knob threaded shaft so I can tell witch version you have!

[Mark Sampson]

Actually, Calumet may still have spare parts available for this camera.
It's certainly the VW Beetle of 4x5 view cameras, by which I mean simple, rugged, functional, long-lived, inexpensive, and extremely common.
If Calumet can't help, try taking the front standard apart to see what's there; it should be quite similar. That might give you ideas about what ordinary hardware would work for the rear standard.

[E. von Hoegh]

Without seeing the parts, I probably shouldn't comment. However, I cured a similar problem with a short piece of hardwood dowel.

[Vlad Soare]

Thanks for the replies, guys. I took some pictures of the parts:

http://img521.imageshack.us/img521/3984/img4203mickb2.th.jpg (http://img521.imageshack.us/my.php?image=img4203mickb2.jpg) http://img179.imageshack.us/img179/2774/img4202micdf2.th.jpg (http://img179.imageshack.us/my.php?image=img4202micdf2.jpg) http://img521.imageshack.us/img521/2879/img4199mictb3.th.jpg (http://img521.imageshack.us/my.php?image=img4199mictb3.jpg) http://img179.imageshack.us/img179/6197/img4196micyh4.th.jpg (http://img179.imageshack.us/my.php?image=img4196micyh4.jpg)

Click on the thumbnails to see an enlarged version.

[Kirk Gittings]

The pressure plate may not be creating enough pressure to give good friction for lockdown. Flip it over and reinstall, now using the curvature to you advantage. The wheel or track may be too worn down too. All these parts are still available from Calumet.

[Vlad Soare]

The pressure plate and the wheel seem to be fine. The wheel works perfectly, it doesn't slip at all, and the standard moves smoothly along the rail. It's just the lockdown that doesn't work.

I looked at the front mechanism. I could see something inside the hole, underneath the locking knob, something that looked like plastic (maybe it was that nylon bearing Will mentioned above). I guess the knob pushes this down against the reel.
Inserting a small piece of a wooden dowel might work, but the groove in the rail is pretty wide, leaving only a small fraction of its edges visible through the hole. The dowel will have to be large enough to catch on these edges so that the knob won't push it inside the groove, while at the same time being small enough to be able to move up and down through the hole. Maybe it would work if the dowel were thin enough to easily enter the groove and long enough to reach its bottom, and so the knob pressed it against the bottom of the groove instead of its outer side? :confused:

[Kirk Gittings]

Yes you are right. It sounds like the plastic button deal must be worn down. I have never replaced that.

[Will Thompson]

Do you have the brass / bronze metal plate that slides in the rail shaft groove under the locking knob that has a notch where the nylon bushing and locking screw meet? When in place you should see the edge of it when you look down the hole the locking screw goes in to. In your photo I do not see it. With the locking screw out it will slide out down the rail. If you carefully (keep the rail level but upside down)remove one of the other locking screws that works you should see it and be abel to copy it.

[Vlad Soare]

Will, I don't know what plate you're talking about. I don't see anything like that. Maybe it's because I don't know what to look for, but I can't even see it in the front mechanism. On the rear side there's just the hole and nothing else. On the front side the hole is completely filled with something that looks just like the surrounding material, but feels like a kind of hard plastic. It's hard, but sounds differently when I touch it with a screwdriver, it sounds like plastic, not metal. I can't see anything above or around it. There may be a metal plate underneath, but I can't see it. In fact, I'm looking at the rear mechanism and I fail to see where such a plate could go. The whole block that moves along the rail is one piece, and it's seated flush against the rail. I can't disassemble it and there's no space to insert anything between it and the rail. :confused:
I'll could take some more pictures from other angles if that were of any help.
In the meantime I wrote to Calumet to ask if they still provide these parts, but received no answer. I see they list ground glasses and lensboards for the 400 series on their site, but nothing else. :(

[Will Thompson]

It looks like the plate is missing. When I took apart one of my 400's the plate fell out on the ground. You must slide the standard off of the rail to do this I think since that was what I was doing when it happened to me. If I get time and you nag me enough by PM I might take one apart and show you the photos.