Russman

My Feedback: (12)

I am assembling an H9 Extra 330L. I have built and flown many giant scale planes but this is my first with 2 piece wings. The instructions show using a 4-40 screw through the wing and tube to retain the wing on the tube. The tube isn't very thick and would only be 1 or 2 threads holding once I tap threads in the tube.This doesn't seem very secure to me. Is this normal for 2 piece wings? Won't the screws get loose during flight? It doesn't seem like you could tighten them very much. I am looking forward to drawing from all yallz experience. Thanks. Rusty

NSSHERLOCK

Regarding wing tubes: Folks in my area have been using a hose clamp aroung the tube housing to anchor the tube so it won't spin or slide from side to side. We have been using a bolt from inside the fuselage into the 1st wing rib (glued into the foam with either a threaded dowel with a bolt or backwards with a 1/4 x 20 all thread glued in the wing and extending into the fuselage, then securing the wing with a wing nut or some such. there are various ways to do it. I would not recommend drilling the wing tube anywhere but near the end. You mentioned no material to hold the tapped thread. Try epoxying a big 1/2 dowell piece inside the wing tube (hardwood) and when you drill and thread the tube you will also be cutting threads into the wood. This should secure the bolt enough that it will not fall out. A couple of us have drilled a hole thru the incidence pins and securing them with a catch pin of some kind as a secondary protection in case your bolt fails for some reason. this will prevent the wing from pulling out enough to clear the anti roll pins and creating a disaster.

BigD

My Feedback: (179)

Do not depend on the flimsy wing tube bolt to hold the wing on. My first 330L suffered a crash on the third flight when the starboard wing folded....it is much better to tap the wing root with 1/4 -20 holes and bolt them to the fuse from the inside of the fuse....it also makes the wing roots fit the fuse better, since they usually come with a large gap!.....at a minimum, you should tap the tube for a much larger bolt and use the inserts that the previous post suggests.....good luck!...

ebackscheider-RCU

I have this plane currently and had the same question/problem. I did fly it last year with just the pipe tapped. This year I added a few layers of plywood with a blind nut. The tapping was stripped out and did not hold anymore.

I have not done the tapping at the root yet, but do plan on it. I do have a pretty big gap between the right wing and the fuse.

Eric Backscheider
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Russman

My Feedback: (12)

Thanks for the input guys. I think what I will do is epoxy a piece of hardwood inside of the tube for a better bite for the 4-40 screw. Then tap the inside of the incidence pics and glue in a stud.Once the wing is installed,screw a wingnut to the inside of the stud. That outa hold her!


Eric, was your plane destroyed? Have you built another?

ebackscheider-RCU

No this plane was not destroyed. I do a VERY close exam before every flight. That is where I found it.

Last year on 6th flight I lost the H9 Edge 540 due to Wing failure. H9 did replace everything so I am not upset, but I do as a result check my planes even more than I did in the past.

Eric Backscheider