Questions on CA Hinges
 

I have a question on CA hinges. Are they suitable for Large and Giant scale aircraft? Please advise me on this. CA hinges, In my estimation are a tad on the light side. P.S. I also pin both sides of the hinges, nylon or CA. Good and bad points in the CA hinge?
Thanks for your input

RE: Questions on CA Hinges
 

I have never had a problem with CA hinges on my birds up to my Super Stearman with 25cc gas engine.
Included are a Showtime 90 and 1/4 scale RV-4 that have both been wrung out repeatedly.

RE: Questions on CA Hinges
 

I have used CA hinges on 150 size airplanes with no problem.

RE: Questions on CA Hinges
 

The pattern guys use them all the time on their 2 meter planes.. I have them on my planes, Excelleron 90 and Venus II, both 120 size pattern planes. The Goldberg Tiger 120 has them, as well as the Seagull Super Star 120.

They work fine. Just use more than they suggest.. if they call for 4 of them on the ailerons, then use 5.

CGr

RE: Questions on CA Hinges
 

Properly installed CA hinges I've found to be problem free.

As many advise, I drill a small tunnel down each slot to help allow the CA to wick deeply into the wood and hinge.

FWIW I really like the Radio South 1/4 scale blue hinges on anything larger.

RE: Questions on CA Hinges
 

I've used them on a 72" Fokker Dr.1 and a Giant Stinger. No problems. Use CA hinges specifically made for giant planes. Follow the installation carefully.

CA Hinge Installation

There are several rules to follow for an easy, correct CA hinge installation. These rules are good for hinges from different manufacturers, including Great Planes and Radio South. I’ve used them on many planes from pylon racers to Unlimited class Fun Fly planes to even a giant scale Stinger (the 1/4 scale size hinges).

I have seen only two in-flight hinge failures. One failure was from catastrophic flutter, which also destroyed the wing panel. The other was due to doubled hinges and the use of thick CA.

Here we go:

Use a #11 blade to cut the slots.
Cut only once per side/per hinge.
Use only thin CA.
Do not double the hinges.
Do not use “kicker”.
Install after covering.

1. Slot the wood pieces, install the hinges, and mount the control surface. Gently push the pieces together.
2. Flex the control surface both ways for the maximum amount of travel you expect to use. This will automatically create the proper hinge line gap.
3. Slowly drop 3-4 drops of CA on each hinge at the hinge line on one side only. If any CA puddles in the hinge line, blot it with a paper towel.
4. When that is dry, apply 3-4 drops of CA to the other side of each hinge.
5. When both sides are dry, flex the control surface both ways.

That’s it! The wood will pull out before the hinge will let go. The surface will tend to stay centered and will not flop around. Both will help prevent flutter.

RE: Questions on CA Hinges
 

CA hinges are JUNK. On one glow plane I lost one aileron, one rudder and two elevator halves, (at different times), ...on a single plane. (If you count them all, I have had AT LEAST 18 CA hinges fail in-flight.

Before I went to gas and giant scale, I switched to Robart hinge points on my glow stuff. All of my gassers have pinned hinges wih Gorilla Glue and, if needed, CF pins through the balsa.

CA hinges are nothing more than a cheap way to sell an ARF. Upgrade your hinges or learn to fly with a broken control surface or two...very quickly.

There is one exception, Radio South has some Mylar CA hines which are excellent, but I still use pinned hinges in all my planes.


There will be many more who say that CA hinges are fine, and they ARE, if you don't actually USE them.


Run away....FAST. Get a Robart hinge-point drill guide and some hinges. Get some Gorilla-glue and keep on flying.

Have FUN!!

RE: Questions on CA Hinges
 

I would not recommend using these on giant scale espcially aerobats. why? well why take the risk. these have been known to fail on a lot smaller planes and i have personally had a whole aileron snap off (not pull out) using these hinges on a 90 size plane. Personally i wouldnt take the risk using these on a big model, grab some robarts

RE: Questions on CA Hinges
 

The suggestions made by DR Driver are excellent regarding installation of CA hinges. One additional little trick is to draw a line on the hinge line on both sides with a wax pencil or crayon, before installing the hinge. After the hinge is installed and thin CA is applied, the CA will not penetrate the hinge line and the hinge will remain very flexible.
The heavy duty CA hinges from Radio South are very good for use on large scale models.

RE: Questions on CA Hinges
 

One of the most important things to remember about CA hinge installation is NOT to apply the CA twice to a side. Once you have let the 3 to 5 or so drops of CA to wick in, do NOT add more to that side. Go on to do the other side and don't do anything further with the CA. Double additions will only cause the hinge to come apart inside where it had formerly bonded with the balsa. I had that happen to me on my Tiger 60 and ended up re-hinging the ailerons because of it.

CGr.

RE: Questions on CA Hinges
 

(If you count them all, I have had AT LEAST 18 CA hinges fail in-flight.

Then you're not installing them correctly.

Dr.1

RE: Questions on CA Hinges
 

I must agree.. sorry Agexpert.. but the main problem with installation of CA hinges is not installed properly. That's not intended to be an affront to you, just a reality of what happens. Most of the problems I've heard of, both here and at the field, is when someone does the CA to them twice. The second application actually de-bonds the hinge and they come out, or become brittle and break or tear.

The big boys at our club all use the CA hinges with confidence.

Now, that's not to take away from pined hinges, and other types, just that I've had good experiences with them once I learned how to install them properly.

CGr.

RE: Questions on CA Hinges
 

I gotta say, in 25+ years I've seen CA hinges on trainers, sport planes, competition fun fly planes, sport models, giant scale, and even pylon racers. They work.

Dr.1

RE: Questions on CA Hinges
 

Yup, Dr. They do work, and work well. As I said, my Tiger 60 had a loose hinge (think two of them, in fact) as a direct result of the double application of CA. I ended up removing the ailerons and re-hinging them. That plane still flys today.. and it's several years and many many flights old... and pretty well abused.. it was my second plane after solo and I surely abused that thing. Fortunately, the ones that broke were close to the fuselage and I noticed them right away.

CGr.

RE: Questions on CA Hinges
 

don't use CA on the CA hinges :D
mmm.. unless you're young and super dooper fast, fast or love the art of re sloting hinge slots.

I don't know...i like my control surface to be posistion as perfect as posisable.
By the time you set the CA bottle down...it's too late to adjust it.lol

You know how they say...apply CA to wood to make the wood hard...in the build process.
Will if you makie the hinges hard and then have a crazy notion of wanting to flex it a million times after.
I imagine a crack will develope.

I never had any problems with them in my .60 size model.
mmm..I don't know...I make extra slots here and there and prepare the hinge area accordingly.

Just makeusre it's done properly. Makesure the slots are clean...especially if you're using an exto knife.
Sometimes there's small slices of wood in there....so the glue will only bond to that slice.
That's where tooth pick or pins comes in to play.

RE: Questions on CA Hinges
 

Again.. I don't know about that. If you plan ahead and do the hinge and surface right the first time, when you get ready to set the hinge with CA, you should already be there.

I have built quite a few lately with CA. One comment I got from the 'club pro', who has been building for over 35 years now, was that he was very impressed with my aileron, rudder, and elevator hinging on my Seagul Super Star 120. The gap was almost non-existent and the flexibility was there with complete movement available on all three surfaces. There will always be a gap present no matter what hinge you use, realizing the need for gap fillers, or covering that will eliminate the gap for better performance.

A lot of this is completely dependent on the initial setup and the proper slotting of the hinge line on the movable and fixed surface. Centering is really what it is all about, and having the centers really on center is very important. Of course, that goes for all sorts of hinging jobs, be it pinned, CA or whatever else you may want to do.

The nice thing about CA hinges is that you don't have to worry about geting epoxy in the hinge itself.. I know.. preventative measures are required, but it doesn't happen with CA hinges.

It again becomes a ford - chevy discussion. There are many people for CA hinges and many against as well as as many arguements for and against them. I prefer them, and will use them, and I ain't a spring chicken either... ;)

CGr.

RE: Questions on CA Hinges
 

I don't mind a little gap here and there...if there was to be a gap...I like for the gaps to be same size gaps.lol

RE: Questions on CA Hinges
 

Gap fetish, eh? :D

RE: Questions on CA Hinges
 

I have them on models up to a 27% (43cc) Ultimate. Zero failures since I have been using them. I also like the removable pinned plastic hinges but CA is good enough for most applications. Check out MinnFlyer's tutorial. Drilling the pilot hole (I always do) and exposing the bare wood on either side of the slot appears to help a lot. I have destruction tested control surfaces on crashed models (can't blame a mid-air or a low roll ground strike on a hinge) and even after hard slams they outlast the surrounding balsa. I also use FRESH thin CA when it is time to hinge. Pin the center so you know you have equal amounts in both surfaces and drip 4 to 6 drops per side depending on size.

http://www.rcuniverse.com/magazine/a...?article_id=55

RE: Questions on CA Hinges
 

Ditto.


Then you too are not installing them properly. They should be adjusted BEFORE the glue is applied.

I am amazed at how many people do not install CA hinges properly, and then discredit the hinges.

See the link Charlie posted above. Installing them is easier than any other hinge method I have ever used - and I have used them all

RE: Questions on CA Hinges
 

Minn.. have you ever heard of what I mentioned about "double application of CA on hinges"? Meaning, applying the 5 - 6 drops of CA, turning the surface over, flexing the surface and applying 5 - 6 drops on the other side.. then leaving it alone.. double application comes in when people go back and add more CA after the original application?

CGr.

RE: Questions on CA Hinges
 

Another note - they are Great for reenforcing attachment points for cowls. CA them inside the cowl centered on the screw holes.

RE: Questions on CA Hinges
 

I have been using them for over 20 years, since they were the new hinge, and have never had a failure. Of course I'm the guy that reads the car's owner manual too! All of the failures I have seen is directly attributable to improper installation. The wax pencil\crayon tip is good, I'll try that. I also put two pins on the center line when I install them so the hinge doesn't push too far in one side or the other.

RE: Questions on CA Hinges
 

By the time you set the CA bottle down...it's too late to adjust it.lol
Go back and read my method. You adjust the gap BEFORE you apply the CA.

I imagine a crack will develope.
You imagine wrong. CA hinges are made of mylar with a cloth bonded to it. The CA soaks into and sticks to the cloth, it does not stick to the mylar which is the actual hinge material.

To restate my directions:
The CA should only be applied once to each side.
Only thin CA should be used.
The CA should not be allowed to puddle on the hinge or in the hinge gap.

Dr.1

RE: Questions on CA Hinges
 

Actually, the wax pencil/crayon trick really doesn't do anything.

If anything It's NOT a good idea.

Look at it this way. A CA hinge is a plastic ribbon with a fibrous coating on both sides. When you add CA, it wicks its way into the fibers.

When you draw a wax line on it, that line sits on top of the fibers - so the CA will still wick under it, but now you have created a barrier on top where CA can "pool" because it can't wick into the fibers like it's supposed to.

RE: Questions on CA Hinges
 

Dick, a Double application of CA is a definite No-no

RE: Questions on CA Hinges
 

Good point, Minn. I never used the wax line myself. I always relied on sight to determine the approximate center of the hinge. This ain't rocket science, people. I've put CA hinges into a 1/4" square balsa TE with a solid control surface and they never pulled out, so I guess the exact center isn't necessary.

Dr.1

RE: Questions on CA Hinges
 

Thanks Guys for your input. I will try, let me say try to install them correctly. I built planes 30 years ago, and the CA hinges were not invented yet, so I stayed with the old nylon hinges. They do take more time to install, but what I have learned here is,Ca hinges is the way too go , installed properly. I will use them that were supplied with the ARF's. Thank you for your comments.
Paul

RE: Questions on CA Hinges
 

Well i learned something on this post and will have to check the Eratix I just got thru with. I did go back it think and put extra CA I did one side the other then went back to the other side again. I did not wait or anything. But did go back and repeat the process. Do you guys think not waiting over 15 sec. while doing the other side will matter. I pulled hard on them after hinging. They seemed fine. I always get mine lined up with a T-pin in the center but then pull them out right before applying CA and push my ail. up tite. Still end up with gaps but very small and from the wood not being completley straight on either side.

RE: Questions on CA Hinges
 

Kid, applying CA like that won't hurt, but the excess isn't needed either.

As for the gap, you NEED a small gap. Very often CA Hinge failure is due to people trying to close the gap completely.

Please read the link above for installing CA hinges and you'll see why

RE: Questions on CA Hinges
 

For those of you with too much time on your hands;

There are many of us who have endured the inadequacies of CA hinges. We know how to install them, but later realized that they are just not sufficient for our style of flying. As I clearly stated, they are JUST FINE if you don't actually use them. People who fly with maximum throw, repetitive inputs, high stresses and who fly hundreds of hours that way should stay FAR away from such JUNK.

It's great that you can fly big ovals for a hundred years on paper hinges, but some of us don't fly that way. Any application with more than 30 degrees of throw, repetitive cycles and high aerodynamic stress requires and ACTUAL hinge, not a piece of glorified construction paper and some krazy-glue.

Get over yourselves. Just because some of us have found the limits to a design DOES NOT indicate, necessarily, that we are incapable of following SIMPLE instructions.

Jeez, what a bunch of know-it-alls. Ask yourselves why there are so few younger people entering this fine hobby, but do so in front of a large mirror.

CA hinges are JUST FINE for light applications. Technology has granted us more powerful TOY airplane engines, lighter TOY airframes, better TOY airplane design and frankly, we have outgrown paper/saran-wrap hinges. They are JUNK when used in a modern high performance TOY airplane...but they are just fine in any trainer of 'warbird'.

Seriuosly, do you really think you are that much smarter than everyone else, or are you just afraid of the little 10 year-old kids who can out-fly us all?

It's pretty sad, in my opinion, that anyone would assume that repetitive failures of a given design could only be due to 'improper installation'. Just in case you didn't notice, many of us can read, follow instruction, fly circles around you and give sound advice too. It's great that a man with over 30 years of experience in the hobby is willing to give advice, but he should be willing to take some too. (Not to mention that his knowledge of a constantly-evolving technology is as much as 30 years old).

This hobby is not just about scale warbirds anymore. It's a multi-faceted group with diverse interests and we are being ignored by the very people whom WE PAY to advance our hobby.

I, for one, have access to large PRIVATE acreage. That is where I fly. I have grown weary of club politics. I am selective about whom I invite to fly with me, and I can afford to have planes buit for me.

Please don't make such bold assumptions. You look foolish. CA hinges are not intended for CERTAIN styles of flying. We are not idiots, we can read and follow simple instructions. I appologize for my lengthy post, but I have grown weary of those of you who just plain REFUSE to acknowledge that this hobby is changing for the better.

With the advent of 2.4GHZ freq-hopping technology, the necessity of dedicated flying sites will wain. A runway is just a flat spot on the earth, nothing more. A club can exist independent of a flying site and I suspect that many more will...Again I apologize for my passionate response, but I am a bit frustrated by the stubbornness of the 'old guard'.

RE: Questions on CA Hinges
 

Your point is well taken, but this is why I emphasize that before gluing, the control surface must be deflected MORE than it will move in flight. The problem here is that if you fly with excessive control throws, this will create a larger gap than some people find comfortable. I have actually SEEN people move the surface, and then say, "That's too much gap" and then close the gap a little before adding glue. BAD MOVE.

So agexpert has a good point, if you plan to fly 3-D you may want to consider something like a Robart Hinge Point or other pinned-type hinge.

RE: Questions on CA Hinges
 

Heck. I thought CA hinges were the new cutting age technolong that the "new kids" brought about and I was adapting quite nicely. :D:D:D

When I'm not ARFing around I take the time to set pinned hinges as I do prefer them.

Yep. That's me. Slow, lazy racetrack patterns. :)

Age and treachery can always triumph over youth and skill.

People skills have to be practiced just like flying skills. ;) If you give up when it gets hard you don't develop and get stuck doing race-track patterns and getting nowhere.

RE: Questions on CA Hinges
 

Well, agexpert, you and I couldn't be farther apart on this subject. You know what you know and I know what I know. Anythng I post in here I've either done or seen done successfully. Your mileage may vary.

I, personally, have installed CA hinges on pylon racers, a giant scale Stinger, and Unlimited-class competition fun fly planes. That's about as extreme as you can get. BTW, Unlimited-class competition fun fly was what 3D was before people knew to call it 3D. When you're doing 3' diameter loops 4' off the ground at full throttle, that's extreme. This is on a 48" wingspan plane with 5" wide ailerons and a 4" wide elevator. A .32 engine typically turning a 10-4 prop at over 15 grand.

Minnflyer makes some good factual points. If you make the hinge line gap too tight, you'll stress the hinge. If you do any of the other no-nos other posters, including myself, have mentioned, THEN they will fail.

I don't fly lazy circles. I have a self-designed Miss Martha-type that'll run about 100 mph and will cut its own tail off in maneuvers. All at full throttle. 3 turn per second rolls and a vertical rolling full throttle Death Dive that ends with a square corner pull out. That's extreme.

I'll repeat and stand by it - if your CA hinges are failing, they're not installed properly.

And on that note, I'm outta this one.

Dr.1

RE: Questions on CA Hinges
 

Use everything that comes with the plane, CA hinges, linkages, tanks, and so on. Then when your plane crashes tell the manufacturer their BS failed and you want them to send you a new plane!

Personally I've never used CA hinges. Always used dubro pinned hinges and after many flights they even have a tendency to come loose. But, since I pin the dubro with a toothpick on each side after I install them they never pull out completely.

If I ever did use CA hinges I'd be sure to pin those on each side too with a toothpick.

Next time you go out to eat, grab a handfull.

RE: Questions on CA Hinges
 

Does not the manufactuer selling the planes ARF"S send what they think is the best pieces at the lowest cost to them. It would not be less cost if they were having hinge problems. Do the really big planes use fiber hinges I have seen them on several 100 size planes and have them on a couple. I am not good enough to break them i guess lol. But do planes such as say a 27% Cap 232 come with fiber hinges? I am pretty sure my buddies came with robart type hinges. With his ARF package. Man i have done some of the stunts that have been described above but then had to take on oxygen. Something to get me breathing again lol. But i for sure like there easability. Someone never had a plane can set there hinges if they just read the manuel of how.
Minn i was thinking that well you know guys put hinge tape to cover the gaps so that is why i take the pin out and get close as possible. Have never had one come out or anything but do understand your gap point and may go back to leaving the pin gap. Thanks guys learn something everyday.

RE: Questions on CA Hinges
 

My Ultimate 1.60 (43cc Fuji) 30%+/- came with CA hinges and that's what I used to hinge it.

Might be interesting to ask of those who have had fiber hinge failures whether they balance their props and spinners? Vibration will stress any material and stress causes failure. And a model should be flown on a fast low pass occasionally to listen for flutter, as well as a pre-flight to spot signs (opening of the holes in control horns or servo arms from vibration). About 20 seconds of aileron flutter will also do in a CA hinge, so if you're overpowering the model and underthinking when to reduce throttle it could have fatal results.

You don't blame a $50 Michelin tire that fails because you're doing 150 mph down the highway and it ripped apart. That's misuse of product. If you over-engine you should over-hinge and over-control linkage. That's just common sense.

RE: Questions on CA Hinges
 

Well, Age.. you certainly told us. And we certainly appreciate that.

Have a good day... and don't use those CA hinges.. but I hope you won't mind if we continue to do so becaue we trust that we installed them correctly.

We've beat this horse to death, that's for sure. As Dr., I'm outta here.

CGr.

RE: Questions on CA Hinges
 

I use ca hinges on all my planes. I have found out that the great planes ca hinges are complete crap. They will hold fine in flight. However when I deadsticked my extra and planted it preaty hard the hinges came right out on the rudder. The fibers stayed glued in the slot but the plastic part that was the inside of the hinge ripped out.(They are plastic hinges coated with a fiber material that wicks the ca and holds to the wind) I'm using radio south hinges now.

RE: Questions on CA Hinges
 

I've seen some hinges that the outside layer.. ?? came off like some sort of covering. I tossed them and opted for some Dubro's that I bought at the LHS. I don't recall if they were Great Planes or not (the ones that came apart on me).

CGr.