Lost an elevator this weekend due to ca hinge failure.
Ive used them on 5 other planes with no trouble.
I know the reccommended installation prceedures, pins in the center during installing, wax the center line ect..
I see this as very positive though, in that the plane, a 4*120, is remarkably, not extremely damaged and it happened prior to completing a 1/4 scale project Im working on, which, I may have made the same mistake on.
Oh well, never learned anything the easy way.

Sorry for your loss, i just recently got shot down so i can empathize.

I was wondering why you wax the centerline of the hinges? It seems like the glue might have a harder time wicking up into the joint with wax in the way. You might know something i dont.

I've never heard of waxing the hinge either. I suspect that may have been your problem. The wax wouldn't let the CA wick to all parts of the hinge. Also, make sure you drill the hole (3/32"?) into the slot to give the CA a path to follow to the far reaches of the hinge.

Does anyone use pinned hings any more? I just spent a few happy hours fitting hinges to elevator of my scratch-built 'sort-of' Wot 4. Kavan hinges, fitted into carefully-cut slots, then pinned in place with hardwood pins. Took time, but what else am I going to do with it?

Never tried these 'instant' hinges and dopubt if I ever will.

The wax keeps the ca from stiffening the hinge in the center where the hinge is bending. The wax does not prevent the ca from wicking also IMHO the hole drilled in the center is not necessary for the thin ca to wick all the way through the hinge.

Patrick

Did your hinge break or pull out of the slot?

Flap, did you read this?

http://www.rcuniverse.com/reviews.ph...ew&reviewid=55


As far as the wax line goes, here is my feeling on that (and it IS only my opinion):

CA hinges are a plastic strip covered with a fibrous coating. Making a wax line will not prevent the CA from wicking under the wax unless you have pressed so hard as to completely seal all of the fibers. In either case, unless the line is drawn pencil thin (hard to do with a crayon) and is kept perfectly straight, the wax may impede the CA from flowing into the wood. So I avoid it.

One of the biggest mistakes people make with CA hinges is to try to completely close the gap, thereby not giving the hinge room to flex which usually leads to a broken hinge. Allow a gap to form, then seal the gap afterward with covering, tape, or whatever method you like.

Please read the link above (if you have not already done so).

I take issue with the fibrous costing seperating from the plastic of the hinge allowing the hinge to pill out and leave the fibrous material and the glue in the slot that;s the way mine always failed.

JIMESTES,
Hinges broke.

MinnFlyer,
Guess your right on about the wax pencil not working, the hinges broke, however, the hinges are still very secure inside the elevator and stabilizer.
I hadnt seen that particular thread, however, have seen enough combined to have read the information given.
The hinge gap was sufficient to allow free and excessive travel prior to contrioll horn installation.
Considering all the precautions taken, if I still am in error, then I feel that the hinges require too much special attention to be anywhere near worth the effort.
I will now go with Robart or Dubro from now on.
To all, as Ive said, I have used ca hinges with no problems in the past and there may well have been something I could done during istallation to have prevented this problem from occurring, however, I believe its in my best interest to try a different product from now on to protect my investment and fun.
Have fun
Roger

I'm not confident in using CA hinges. I might be all wet but I haven't ever had a pinned hinge fail. One thing I have read in the thread's about CA hinges, their not for planes over 40 size, generally. Maybe the 120 control surface was just too much stress on them.Like I said, this is pure conjecture as I haven't used them. (too chicken) BWAK BWWWWAAAAAK BWAK

I never use anything but Robart point hinges . Yes they are a pain to install but after losing two planes to various hinge failures I learned my lesson.

I have broken all the hinge rules on my last two projects, a Goldberg Extra 300 and a GP Extra 300S.

I have made the slot a touch bigger and have used Titebond glue. I tested both the plastic hinge on the Goldberg and the ca hinge on the GP in a block of balsa stock and when left overnight I couldn't pull them out with a pair of pliers.

Keeping my fingers crossed

Bob

Bwindrum, The most common mode of failure for plastic hinges is when the center pin wears out and works its way out ( lost one plane this way) . therefore there are many ways for a hinge to fail . Check your hinges before each fight.

I initiated a thread about ca hinge failure this past autumn. I have used ca hinges in the past 6 or 7 yrs without failure and now I lost 3 hinges on my TF P-51B (red box) Mustang. I never lost the plane. I got some good advice and some pupu on RCU. When I built the Mustang I installed the control surfaces WITHOUT a gap. It looked good but a tension type stress was put on the hinges and they don't take it real well. I got one response on RCU saying that a ca hinge will crack immediatly if the hinge is bent where ca glue is applied. I put ca (super thin) on a hinge and attached it to my drill press and it was bent 100 times per minute for over 15 minutes and I spotted no fatigue. The was bent over a small radius also. I left a small gap on my P-51B and no problem although I only flew it 4 times since I fixed it.

Listen to what Foxx said. Check them before each flight, or at least before you head out to the field. One inspection of my GP Ultimate bipe revealed 6 of the hinges on the ailerons were split in half. At any rate, sorry about the loss. "Experience is something you get right after you need it."

All CA hinges are not created equal. The only ones I have used are either Great Planes or Sig, and I have never had a CA hinge fail in any way, shape or form. But they say God watches over children and fools... and I'm no child

I cut large slots and use Medium CA for my hinges, and I have never had a failure. In my opinion, the thin CA makes the hinges too brittle. I am using CA hinges on my DP Extra with success, including 3D rates.

Hey Mike you forgot the drunks

Yes... I have forgotten many drunks in my time

I suspect, that, had I checked them as I have often not done, prior to each flight, I would still have my plane in tact as Im sure all hinges that failed surely didnt fail all at once, so, we may deduce pilot error due to poor preflight inspection of aircraft.
That said, I must tell you that not only were the ca hinges reccommended for the 120 size plane, they actually came with the kit along with specific installation instructions which were not only followed, but, improvised on to prevent such a misshap.
Prior to sat., I couldnt be persueded not to use the ca hinges, now, Im determined to never use them again.
I havnt tried any other type hinges, though HOOTER, who also flies at the same club, uses the Dubro hinges with dowel reinforcment and has never had an aircraft failure, other than dead stick, so, I purchased the same and will install those before next flight.
I used to think, the simpler the better. The ca's had no pins or working parts to fail, so, thats what I went with untill this happened.
Live and learn, die and forget it all.

Flap,

I was luckier than you I got to hear the elevator flutter and could feel my stik not turning like it should and got it on the ground. This is the second instance of ca hinge failure that I have seen. So I will never use anything bit pinned hinges again. But I have learned something from my mishap, whether ca hinge or pinned I pull on each of them before I fly. Paranoid I guess. How is the repairs going, hope to see you this weekend but the weather looks like crap.

Later

Jimmy

Jimmy, got the firewall back in sat, but, Ill be traveling this weekend and wont likely get to fly for 2 more weeks, so, I fell back in on the Cub for a while.
Only real challenge is that the bottom of the former which is above the landing gear mount that holds the leading edge wing dowels in place is destroyed, so, I got to make a partial former perfectly to hold the wing in alignment. Other than that, just a canopy and wheel pants and a couple of holes poked in the fabric.
Bottom of the fuse front is still in 1 piece and easily fastened back on.
See ya

Hope you secure that poor old pilot this time!!!!!

AINT THAT THE TRUTH! Now it seems worth puttin up with the ribbin, glad I never wasted time fixin him.