Question on elevator brake repair on Century 2 Stand

[lenser]

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]

Help please.

[Jim C.]

Can you post pics of the elevator mech, particularly the locking mech ?

[lenser]

Will do, Jim. It will have to wait until tomorrow evening as I am shooting a project that's out of town tomorrow.

[lenser]

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]

Sorry, the second image refuses to upload, but it is only a slightly different angle.

[Jim C.]

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]

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.]

Glad I could sort of help, the mech is very simple, I doubt you could set anything out of whack.

[lenser]

Thanks for the vote of confidence. Some of my semi mechanical projects have worked out well....others have been laughably lamentable.