Slop in elevator half.
 

Hello all,

I discovered a problem with my GP Sopwith Camel EP. I discovered that the elevator half that is opposite of the control horn is loose. There is a lot of movement, (about 1/4) inch in the direction of up elevator. No movement, however, in the direction of down elevator. I am aware that the rod that links the two halves has come loose. What would be the best way to go about repairing this problem? I would like minimize adding weight to the tail surface. Could I cut open the covering and wick thin CA over the rod? Should I do the same to the opposite side as a precautionary measure?
It gave me a scare on approach yesterday, the planes pitch was very "jumpy-up-and-down" out of the blue. I was able to land it ok, but it certainly got the adrenaline pumping, not knowing exactly what was going on!! [X(] It acted like it had a mind of it's own!!

~Noah

RE: Slop in elevator half.
 

That should work, provided the connecting rod is a tight fit into the elevator. As a precaution, consider putting a piece of wax paper between the hor. stab and the elevator in the hinge gap. This will help prevent accidently getting glue on the hor. stab.

RE: Slop in elevator half.
 

It depends on the problem...if the rod is glued to wood that has broken loose then I think CA to glue the wood back would be ok.....But if the the rod is loose in the hole...I'd fill the hole with epoxy....

RE: Slop in elevator half.
 

I fixed one by drilling 3 holes over the rod, and I used thick ca. I would have used the 30 min epoxy, but mine was going bad. I had a aileron that I had to cut out the wood that was left, and I made a thin patch with a piece of lite ply, like you would use to make a control horn mount.

RE: Slop in elevator half.
 

Yeah, you really should use epoxy, though. My suggestion would be to try to scrape out any of the glue that is in there, should have been epoxy in the build, as best you can with a sharp new exacto knife. Then put the wax paper keep he stab from bonding with the elevator half, and apply the epoxy using a toothpick or something really small. Use 30 minute epoxy to get the working time, and time to apply as much as you can along the rod and into the securing hole in the elevator half. Let it set overnight and check it closely the next day.

CGr.

RE: Slop in elevator half.
 

Can you tell if the balsa structure is still intact where the torque rod is secured in the loose elevator? If the exterior is still firm then the wire torque rod had opened up / compressed the soft balsa around the rod.

Protect the surrounding area with wax paper as explained earlier to protect the covering. Open up the hinge line so that you have as good of access to the leading edge of the elevator as possible. Use warmed 30-min epoxy (a small glass custard dish in a hot water bath works fine) and a toothpick to drip the epoxy into the rod hole and fill the hole. Maybe a bent really tiny bit of wire can be used to push the epoxy as far into the hole as possible.

Once the hole is filled secure both elevator halves so that they are true to the stab and let dry. Maybe hang the plane from it's nose so that the epoxy doesn't drain out.

Then re-center the servo and re-adjust the elevator throws.

HTH

BTW - The World Models ARFs have this problem with their single servo aileron approach. Fix it before ya fly 'em - been there done that ...

RE: Slop in elevator half.
 

Great guys! Looks like there is a lot of advice here to digest. However, I just got home from a long day, so I will look at it tomorrow. I haven't even cut the monocote to expose the trouble spot in the elevator yet. Was waiting for advice first. I'll post back this weekend (have a long day tomorrow too) with a diagnosis.

Cheers!

~Noah

RE: Slop in elevator half.
 

Ok, so this is what I found removing a bit of the covering from the bottom of the loose elevator half. I discovered that the torque rod had pushed through the balsa, it was set into, on the bottom half of the elevator. So, I used CG's advice on the 30 min epoxy and warmed it as SeamusG recommended and did the following:
1) I cut away the rough edges to clean it up.
2) Cut a piece of balsa to lay back in place of the removed broken balsa.
3) Flexed the elevator a bit to lift up the torque rod and applied the epoxy underneath and around the rod.
4) Reset the elevator at its proper position and placed the replacement balsa over top of the torque rod.
5) I used wax paper and a small clamp to pinch it together. After it dried I removed the clamp and soaked the repaired area with a bit of thin CA to reinforce the balsa structure.

It was odd because the balsa that the torque rod was set into seemed to have the grain of the wood running parallel with the torque rod. One would think the grain would be positioned perpendicular to the torque rod. Wouldn't that give it more strength to secure the rod?

Anyway, the Camel flies like normal again. Thanks for the advice guys!

~Noah

RE: Slop in elevator half.
 

Geez Noah - there ya go "thinkin'" - should be outlawed in this hobby.

Just teasin' - yup.

Way to go!!!!!!

RE: Slop in elevator half.
 

Ha ha!:) Thanks again for the advice SeamusG
You see, if I built this plane, (I don't know if I mentioned it is an ARF) I probably wouldn't have had this problem.

I really want to build some kind of a kit. But lack of space to dedicate to a build is my only problem.

~Noah