450 Trex 450 dfc ball link issues

[zanezany]

Hi guys, I was wondering if anyone have had this same problem.

I've had at least 6 good flights on my trex 450l dominator. Unfortunately, as I was doing a hard turn into a head wind, the blades started flapping, hit the tail boom and crashed bad.( no chance of saving it. The tail boom completely broke in half at the tail boom mount, twisted tail servo linkage rod, main gear shred, and more..(

After inspection, I found that the ball link connected to the dfc swash plate popped out of the linkage ball. Could this be the cause if it??? If yes, how can it pop out? I made sure it was fitted nicely before every flight.. Dampeners were fine too...

Thanks in advance
Zanezany

 

[Tony]

On the DFC links, make sure both ends are screwed in all the way. I mean completely seated. The only linkages you will use to adjust the head is the swash links. And yes, you can get perfect geometry doing it this way.

 

[zanezany]

Hi tony, thanks. The dfc links, both ends were screwed all the way in. It was all in one piece after crash. Only the ball links popped out.

 

[Tony]

Maybe I'm not following. Can you post a picture of the linkages after the crash in which you have a question? I think that would help.

 

[Slobberdog]

that ball link and arm assy drive the swash so the ball link is pushing itself on to the ball, should not pop off when head is spinning

 

[Mda1701d]

If you mean the plastic ball link came off the meat thread, ie the thread pulled out, then I wreaked one of these when first building my dominator. I tried to wind on by hand, and ended up with a thread that started half way in, not sufficient to hold the link together under strain. I found the only way to assemble these is to open the end of the plastic slightly with a stanly blade, then file a small shamfer on the thread, then put it in a chuck on electric drill, set very slow. The plastic link can then be held by hand, while windinding the thread in to the end with the drill. Seems the only way to get them tight!

 

[zanezany]

Hey guys, thanks for the replies.. I'm ready to get back into finding the cause of this problem now. Almost gave up on this anyway, here are some photos taken. as it is. Notice one of the ball link popped out.

Besides the ball link, I'm beginning to think that the crash is caused by a weakened main blade. Probably weakened by some minor crashes before. One of the blades was bent in the middle. And that was probably what caused the Flappings.

Zane zany

 

[D.O.G.]

Hey there zanezany. Don't laugh but I cheat on my DFC set up. I'm using a stabilizer holder connected to a Dual Ball DFC swash plate. This takes the stress of the two ball link. It's been working for me. Just an idea.

 

[zanezany]

interesting. Makes perfect sense.. Damn this ball links. I wish they've made ones with a locking system. Sometimes it Makes me wanna use power glue on these damn thing...

 

[Graham Lawrie]

Dont glue the links they are designed to move Thats a hard tail crash you have had, unlucky The link may have popped off on impact?