Cambo SC help needed
My old Cambo SC 4x5 has gotten a bit stiff on the focusing rails. When I try to focus the front and rear standards, I'm having to physically move the standards rather than using the focus knobs. I played with the set screw on the bottom of the standards to try to adjust the pressure, but nothing seemed to change. Any ideas here?
Try cleaning and waxing the rail. See if the following helps...it won't hurt.
With a water dampened cloth, dab a bit of window cleaner (Windex), onto the cloth.
Wipe down the rail, removing any layers of gunk and old wax...dry.
Re-wax with a very thin coat of paste wax (Johnson's or Renaissance)...buff clean.
I have a similar problem with an older Cambo, has a square section rail. The lens standard works fine, but when I try to lock the film (rear) standard, the locking knob moves the standard instead of locking it. And the rail is very clean, probably as clean as it was when new.
I posted a question about what to lube this with in the Camera Building, Repairs & Modification forum, and got no response.
You both may be looking in the wrong direction.
I have a Cambo standard and rail in front of me. I've fiddled with the set screw on the bottom of the rail rider. It raises and lowers the friction drive roller and as far as I can see its major effect is to affect the ease of mounting the standard on the rail.
The key to your problem, Parker, and the one I created for myself by fiddling is friction drive. If drive roller slides against the rail it won't drive. Mine was a little cruddy, slipped. Cleaning it -- I held a paper tissue against it and turned it ... -- restored friction and its working as it should now. Will move the standard forwards and backwards on a horizontal rail, can't move the standard upwards against gravity on a vertical rail.
Clean your roller and rail, Parker, and see what happens. I know it is counter-intuitive, but friction drive needs friction. No friction, no drive. There are two rollers inside the rail rider's upper section, so it doesn't slide on the rail. You might want to check that they turn freely. You don't have to defeat sliding friction, the bearings in the rail rider do that for you.
George, are you sure you know which knob is the drive knob and which is the locking knob? I know my question looks insulting, but I can't reproduce your problem so it has to be asked. The drive knob is on the left side, the locking knob on the right; the locking knob backs way out, the drive knob doesn't.
Good luck, have fun,
Here is a curiousity related to the general theme of the thread. My SC when used on its original 21 inch rail works fine in terms of a smooth friction drive. But when I mount the same standards on a 10 inch rail the friction drive slips. The 10-inch rail came from ebay but looks to be in fine condition. What would you suggest looking at first?
Brian, I'm not sure. I've had similar things happen when moving standards from one Cambo rail to another or to an 80/20 brand 1" square t-slotted aluminum extrusion. I fiddle and eventually things come right. I also help the standard I'm trying to move go. I generally don't clean rails, but you might try that.
About the 1"x1" t-slotted extrusions, they're the least expensive long rails for square rail Cambos. My 48 incher cost less than $20 delivered.
By the way, I made one misstatement earlier. If the little set screw under the rail rider isn't screwed as far in as it will go (after the standard is on the rail), the standard can rock back and forth a little, giving small unintended tilts. The set screw may have to be backed off to get the standard on the rail.