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lenser
5-May-2013, 18:11
After decades of waiting, I decided to tackle some minor repairs of my Century 2 stand and discovered that the elevator brake has decided to no longer hold position. Every thing on it is intact, but it looks like it has simply polished the wood on both surfaces to the point where it is easy to slide. I tried using a very rough grit sandpaper to rough up the edges on the platform, but that had little effect.

Before I try to dismantle to brake arrangement itself, I wonder if anyone else out there has tackled this problem and might offer me some advice before i step in something deeper than my abilities allow me to complete.

Also, does the rope and garage door style spring tensioning system have anything to do with the hold ability on the brakes?

I've done a few hours of searching the internet and so far haven't found anything related to directions for usage on the system, so if any of you might have that data, I would be deeply grateful for a copy.

Many thanks for any and all advice.

Tim

lenser
6-May-2013, 11:35
Help please.

Jim C.
6-May-2013, 14:12
Can you post pics of the elevator mech, particularly the locking mech ?

lenser
6-May-2013, 18:53
Will do, Jim. It will have to wait until tomorrow evening as I am shooting a project that's out of town tomorrow.

lenser
7-May-2013, 19:02
Here are two images of the business end of the brake on one end. The other is a mirror image on the other end of the shaft in the foreground. The operation seems to simply be wood on wood as a friction brake and it seems that the two surfaces may have just polished themselves to the point where they slip.

lenser
7-May-2013, 19:05
Sorry, the second image refuses to upload, but it is only a slightly different angle.

Jim C.
7-May-2013, 21:23
I assume that you crank up the platform then turn the brake crank to tighten ?

It looks to me to be a eccentric cam, there should be a wedging action when you turn the crank
not just friction, the vertical 'shoe' part should press against the moving column.
Is there play when you push the locking crank front to back ? If there is then the hole that the
crank shaft passes thru could be oval, just enough to not push the shoe against the moving
column firmly enough.
There is also that metal arm that moves the two wood pieces that make the eccentric cam
the square head set screw can be loosened, see if you can adjust it to make that shoe contact
the column more. It may mean jacking the platform columns so that you can make the adjustments
on both sides without them falling.

Hope this quick sketch gives some ideas where to look for play and doesn't confuse you more :)

lenser
8-May-2013, 11:08
Thanks, Jim.

I am less mechanically inclined than most, so I may have a good machinist friend help me work through this. The actual mechanism looks dirt simple, but I don't trust myself with the possibility of getting things out of balance in trying to work on it myself.

Jim C.
8-May-2013, 14:07
Glad I could sort of help, the mech is very simple, I doubt you could set anything out of whack.

lenser
8-May-2013, 15:19
Thanks for the vote of confidence. Some of my semi mechanical projects have worked out well....others have been laughably lamentable.

premortho
8-May-2013, 17:25
I believe the pulleys and long coil spring is to counterbalance the elvating platform. The adjustment is for different weight cameras. I don't think the brake is designed to hold the weight. I believe the brake is only supposed to stabilise the platform and camera. This is the type of stand (but not the same make) that I saw in the photographic studio where my mother had her pictures done, the photographer showed me how even I (at age 6) could raise and lower the camera with a finger. I was admonished to never lift or lower it without first releasing the brake. This was in 1944.

premortho
8-May-2013, 17:41
My mother's favorite photographer had an 11X14 portrait camera mounted on a stand similar to this. She went in every year for new "stills" because womens fashions changed often. By the time I was 6, I was "allowed" to adjust the camera height. This had to do with pulleys, rope, and a coil spring with a tension adjustment on the dead end. He had that 11X14 so well balanced, I, at age 6, could move it up and down quite easily. I was warned to never move it up or down without first releasing the brake. So, I think that's what you have, a stand designed to counter balance the weight of the camera, with a brake to lock it in position after the photographer set the camera where he wanted it. This was in 1944.

lenser
9-May-2013, 20:38
Premortho,

Looks like your memories nailed my problem. I had never adjusted the tension on this (no need in the past) and apparently either I or someone at one of my numerous garage sales may have tripped the pawl on this and let the needed tension slip away when the cog wheel was left without a stop in place.

Anyway. Many thanks to all who responded. The actual brakes needed no adjustment once the tension was reset correctly. Works like a charm again.

By the way, I am using Old English dark wood scratch formula on both the stand and the camera. Gorgeous luster to the cherry wood now.

premortho
10-May-2013, 05:21
I'm happy we came up with the solution to the problem. It doesn't pay to let strangers (or sometimes even friends) play with rare antiques like this.