Those darn springs

[tonyjohnson]

Sometimes I get to parts of the build that seem to be a puzzle. My current puzzle is the springs that attach the manual roll trim to the control column.

I spent about an hour trying to attach them tonight. No amount of 4 letter words, zen meditation or physical force would cause them to go into place on the control column.

Does anyone know the secret to this puzzle?

[flyeyes]

Originally Posted by tonyjohnson

Sometimes I get to parts of the build that seem to be a puzzle. My current puzzle is the springs that attach the manual roll trim to the control column.

(snip)
Does anyone know the secret to this puzzle?

You're not holding your mouth just right ;-)

I don't remember this being a big deal on my airplane, but it's been a few years now since I attached those springs.

I did learn a "spring trick" a few years ago that is necessary to R & R the springs on a Rotax 912 exhaust (a couple of the springs have to come off to let the oil filter clear.

Make a simple tool out of some thin nylon rope and a wooden handle. Something like the pull rope on a lawn mower. One end of the rope is permanently attached to the center of the handle by drilling a hole, pushing the rope through, and tying a bulky knot. Make a loop of rope through the hook on the end of the spring, and wrap the free end around the wood handle. Now you can easily pull the spring longer with one hand, and use you free hand to guide the "hook" over whatever it's supposed to catch on. Once it is in place, unwrap the free end of rope, and snake it back out of the hole.

If this doesn't make sense, I'll try to take some pictures

[tonyjohnson]

James,

Thanks for the post. The problem is not stretching the spring, it is manuvering it to attach to the control column. The end of the spring is a full circle with the bottom where the end of the spring opens being difficult to position onto the clip on the control column.

I am tempted to cut the end of the spring to make a hook that will fit more easily. I hope this makes sense.

[Norman CYYJ]

Hook the spring first to the base of the control column then the trim lever. It shouldn't be a hassle. They usually go on very easily. If not make a little wire loop at the attach point on the control column and then put the spring on it. But first go back and try tomorrow. You might look at things differently and all will be well.

[LettersFromFlyoverCountry]

I may be wrong here but -- at least on a 7 -- I don't believe the spring attaches to the control column. It attaches to a metal tab, doesn't it? And on the other end it's safety wired, I believe.

[cjensen]

You are correct Bob. I just did this a couple months ago...

[Sam Buchanan]

Originally Posted by tonyjohnson

Sometimes I get to parts of the build that seem to be a puzzle. My current puzzle is the springs that attach the manual roll trim to the control column.

I spent about an hour trying to attach them tonight. No amount of 4 letter words, zen meditation or physical force would cause them to go into place on the control column.

Does anyone know the secret to this puzzle?

Tony, I'm having difficulty visualizing the problem you are having so what I am going to share may not apply in your situation.

I made little "S" hooks out of 1/8" stainless welding rod to use as attachments for the springs to the trim handle and the tabs on the control sticks. One end of the hook goes through a spring and the other end of the hook goes through the tabs/handle. Not only is this easy to install but prevents the end of the springs from wearing in the tabs. This arrangement has worked flawlessly for nine years and 850 hrs.

[LettersFromFlyoverCountry]

Theoretically (and practically, too, now that I think of it), the method you use is exactly the same as the method you'd use to put a key on a key ring.

[robertahegy]

Bob and other posters are correct. The other thing is not to stretch the springs too tightly. Not much spring tension is required to change the roll rate and if you tension the springs too tightly, the friction lock will not hold your trim adjustment in place and will constantly slip back to neutral. You just need enough tension to move the sticks side to side with the trim lever and not have them sag.

Roberta