[jlfernan]

Working my 9A QB today I prepped and was installing the control column to the control column mounts. I used the minimum washers so that according to the plans "the control column will move freely". Unfortunately, as soon as the bolts were snug, not even up to torque spec, the column would bind. I tried several combinations of washers, this alone was a hellish experience, but to no avail. Called Vans they suggested lubricating the bearings to ensure they moved freely. Done, no change. I used a small carpenter's square and discovered the right column control mount, which attaches to the spar carrythrough, was not installed square which is what I believe is causing the bearings to bind. I called Van's and was told to call back in a few minutes and speak with Gus. I hope he has a miracle solution because I can't see how to replace the mount with everything around it riveted and bolted together. Anyone out there with any suggestions?

 

[Martin Sutter]

Big Problem

Check if the washers are binding against the aluminum surface of the angle the mount is made from. The bearings are recessed in the thick bracket. Sometimes the edge of the bearing ball is below the surrounding surface causing the washers to bind on it when the bolt is tightened. The solution is to install a small diameter washer next to the bearing.

Martin Sutter
building and flying RV's since 1988

 

[jlfernan]

I finally figured it out. Gus says that the control mount being slightly out of square is not an issue. The bearings are designed so you can be up to six degrees off and the bearing will compensate. He just suggested trying more combos of washers. I found in the spare washers and bolts some 10 washers that are even thinner, .023, than the regular 10L's. Using these I was finally able to get it to work correctly. Now, was I just having a bad day, or is this more difficult than it needs to be?

 

[jcoloccia]

Now, was I just having a bad day, or is this more difficult than it needs to be?

Considering that you where able to fix it with a couple of bucks worth of washers, I'd say you're having an exceptionally good day