Fat Infinity Grip Cable - RV-7 or 9

Noah · #1 05-23-2011, 08:59 PM

Has anybody run a standard blue infinity grip cable out the bottom of their 7 or 9 control stick (no holes drilled)? I did this long ago and just discovered, since I finally have the wings on and am installing the outboard aileron pushrods for the first time, that there seems to be a close clearance / interference between the two heim bearings where the cable runs. This was not apparent when I only had one bearing installed, and I never installed the second one before (what an absolute duh moment).
http://img696.imageshack.us/i/1007rv054.jpg/

Wiring all of those freakin' switches probably took at least 2 weeks. There is definite resistance in the control system as a result.

Trying to figure out what to do now -anybody got any good ideas?

I have 20 pin molex microfit connectors on the ends of the cables and I don't think they can be pulled through the stick without removing all of those delicate little pins... Maybe strip the insulation for an inch or two just where it passes between the two rod end bearings? Maybe put a split sleeve of teflon or something between the bearings? There's got to be a solution that doesn't require major surgery.

Methinks this is one of those moments that Paul Dye was referring to...Ugh...

Ironflight · #2 05-24-2011, 02:57 AM

High Noah,

Yeah....lots of those moments. I don't know if the dimensions are the same (disclaimer!), but on the -3 project, I removed the outer sheath of the blue cable above the pivot point, then split the bundle to go either side of the bolt, then brought them together again to pass between the two Heim joints. I have not installed the wings/push rods yet, but I did put th Heim joints on the stick when I was noodling around wit this solution, and it gave me decent clearances, so i went with it. I did use some snake skin on the wires where they pass between the Heim bearings to protect them from wear.

We'll see if it still works once the actual push rods are in place, but I am confident in this one.

Paul

olyolson · #3 05-24-2011, 05:12 AM

I know a guy that drilled a hole up higher in the stick big enough to get the cable through then welded a doubler around the hole. Yeah, I know what you're thinking but I don't think I could break his stick now even with a very large hammer.
FYI

Noah · #4 05-24-2011, 10:36 AM

Quote:

Originally Posted by Ironflight

High Noah,

Yeah....lots of those moments... I did use some snake skin on the wires where they pass between the Heim bearings to protect them from wear.
Paul

Thanks Paul, I'm definitely leaning in this direction. It isn't much interference, just enough to cause a little friction in the stick motion. What is "snake skin"? Sounds like exactly what I need!

RVbySDI · #5 05-24-2011, 11:50 AM

Quote:

Originally Posted by Noah

Thanks Paul, I'm definitely leaning in this direction. It isn't much interference, just enough to cause a little friction in the stick motion. What is "snake skin"? Sounds like exactly what I need!

Well, I am not Paul and this is not exactly the "snake skin" stuff I used but it is very similar. This material is an expandable sleeve that bundles multiple individual wires. It also can help protect wiring from chaffing.

The stuff I have was from http://steinair.com/ and was multi-colored but I could not find it listed on their website. However, if you call them I am sure they could set you up.