I built a GP extre 300s 40 size arf. Broke the engine in on the plane.
I am using nylon hinges with pins.
During the second tank of fuel I noticed my right elevator half was flapping in the wind, WOW. After careful inspection I found that in addition to the three elevator hinges breaking I had two aileron hinges broken and one hinge on the left elevator also broken. I have not at the time flown the airplane!!!

I fixed all the broken hinges by replacing them. I now have about 70 flights on the plane and noticed two broken rudder hinges and a broken elevator hinge. I have fixed these also by replacing them.

I have alot of airplanes and all of my hinges were installed in the same fashion for all airplanes, but this particular airplane seems to have a nasty tendency for breaking hinges. Actually I have two of the GP Extra 300s (40 size) and the other one has no problem at all. The hinge breaker has an OS 91 four-stroke while the other has a Saito 100 four stroke.

Anyone out there having similar experiences???

Wow, I'm surprised at all of the broken hinges. I use Klett or Dubro pinned hinges on most of my planes, and have never had a problem. Some of my hinges are ten years old and still going strong.

Did the pin come out, or did the nylon tear?

Eric

Just wondering if you are using CA on these pinned hinges?

Gunny

I have used both Klett and dubro hinges, they boke the nylon part, the pin was intact.

No CA, they were all epoxied in. I cut the slot, test fitted the hinge, removed the hinge and used CA hinge material to apply epoxy into the hinge slot, then wiped it down with alchohol to clean excess epoxy, then pushed the hinge into the slot. This is my procedure to install hinges. Works great on all other airplanes.

I have been thinking I may have a vibration problem, and may try installing flying wires on the tail feathers and see if that helps.

Yes I have put flying wires on mine and the hinges held up so far.

Good idea!


Gunny

Try sealing your gaps with clear gap tape. Will reduce the forces on the hinges.

Also maybe the control surfaces are warped and twisting the hinges? Maybe the hinge slots are not straight? I would try sealing them but this is unusual. A bad batch of hinges (doubt it).

I had CA hinges that kept breaking and it was because of 2 reasons. One the aileron was twisted and it was a pretty thick aileron and second the hingle line eas exactly straight down the wing so you had twist and a wavy hinge line. Maybe this is part of the problem.

I am with the last two posts, If the hinge line is not straight something will break after some use which causes flexing on the hinges. Have broken two on one plane and that was the cause which is now corrected, they were DuBro BTW. Covering the gap is also helpful.

Make sure you have no gaps nor slop in the linkage. Sounds like a symptom of flutter to me.