Any of you UCDers break your CA hinges yet? Well mine finally broke in half on both the rudder and one of the elevator. They didn't last that long at all. I'm using 1/4 size Klett pinned hinges now on all surfaces.

Also I don't understand why H9, GP, DP recommends you to use CA hinges on their 1/4 scale planes???? Is it so they break, you crash, and you buy another plane? Do they really save money by using CA hinges instead of pinned hinges?

Yep, my UCD broke a CA rudder hinge on the second flight. But I used a pull-pull rudder, so I figured it could have been my fault.

Then on the fifth flight I broke a CA hinge on the left elevator. Engine is a ST 90, and my control throws are only slightly more than the instructions call for. But then again, the UCD was designed for 90 size engines and 3D throws, right?

The rudder now has four Klett 1/4 scale pinned hinges and each elevator half now has three Great Planes pinned hinges. After five more flights, no more problems. But now I'm keeping a close eye on those CA hinges in the ailerons.

Despite the minor setback of the broken hinges, I REALLY like my UCanDo! The only problem is that after 10 flights, I still don't know if a UCanDo will fly straight and level.

When you installed the CA hinges, did you use crayons to coat the bending area to prevent CA from getting into the hinge at that point?? I've got over 6 gallons of gasoline through my DP 330L using Central Hobbies 1/4 scale CA hinges and not a problem. I also used them on the rest of my fleet and have never had a hinge break yet.

Nope, didn't crayon the hingeline.....but now I wish I would have.

Due to past experiences with broken CA hinges on five previous planes, this time I decided to follow the UCD instruction manual to the letter as far as how to install the CA hinges. And once again, they broke.

It has to be something that I'm doing wrong again and again because there are way too many modelers out there that have never had a problem with CA hinges.

In hindsight, I think the problem this time was that the UCD manual has you put 6 drops of CA on each side of the hinge. Even on my five previous planes with CA hinge failures, I had never used this much CA.

Perhaps 2 or 3 drops of CA on each side would have left the hinges pliable enough to keep them from breaking with extreme control throws? I'd like to think so, but that didn't stop CA hinges from breaking on several previous planes.

Do you think the crayon trick would still work even with too much CA?

I have no doubt that I'll give CA hinges a try again sometime in the near future. It's now become a personal challenge. And next time I'll be sure to give the crayon trick a try. Maybe then I can finally join the CA hinge bandwagon.

where do you guys get your klett pinned hinges? is there a site with a pic of them

You can get them at www.sheldonshobbies.com. I don't have picture but they are about 1mm thick, 1"inch wide.

I've had these 1/4 scale Klett hinges for years. They look like a doorhinge.....very similar to the DuBro 1/4 scale hinges, only molded better.

When Goldberg sold out to Lanier, it sort of left Roy Klett hanging in the breeze. I'm not sure where or if you can buy Klett products today. A search on Google for "klett hinge" got some hits, but I don't know if those web sites are still valid.

CRAYONS hu,
I did'nt know that one.

thank you for the site

I know this has nothing to due with CA hinges, but I'm in the middle of assembling my u-can-do and i was going to install 5 Cirrus metal gear servos they had around 100 ounces of torque each, I've always used these servos for my rudders in all my planes with no problems and this is the first time i put more than one mettle gear servo on the same plane. The problem is that if i move either the ailerons or elevator i get a single glitch on all the other flight controls not a continuous glitch just a hit and it doesn't happen every time you move a flight control but just enough to cause concern, Ive removed all but one of the mettle gear servos "rudder" now and replaced them with 60 once plastic BB servos and everything works great now . is there any reason I'm not able to use more than one mettle gear servo at a time.

You may have a bad servo, try isolating it by adding them one at a time. start with two metal gear servo, if its fine, then add the third one, and so forth until it starts glitching.

That's a new one on me too.

Second flight.....broke a CA rudder hinge.
Fifth flight.......broke a CA elevator hinge.
Today, about flight number 20.......broke two CA aileron hinges.

dang!

Dave, you've got to be doing something wrong! That's just too many broken hinges. There are a lot of people using CA hinges with no problems.

Many pattern fliers use CA hinges on 2 meter pattern planes and put literally thousands of flights on them without any troubles.

I know that pattern planes don't use extreme throws on all control surfaces but they do use pretty large throws on the rudder. There's just got to be something wrong with the way your installing them.

Why don't you describe exactly how you installed them and maybe someone will pickup on your error. I remember a thread a while back where some guy had similar problems and he didn't realize that you were supposed to insert them before putting the CA on them. I think he was putting medium CA on them and then sliding them in. I'm not suggesting that you're doing this, but there must be some detail of what you're doing that's causing your problem.

Also, if you describe your approach include what type of CA you're using, what brand, and how old it is. This sometimes makes a big difference.

Best of luck,
Keith

On my pattern planes I used CA hinge but on all my 3D planes I have always only used pin hinge...

If I ever received my ucd I have got Klett hinges for it

I have rip hinge before on very wild throw...especially on double bevel surfaces!

Daniel D.

These shouldn't be breaking very often....

Taking each control surface... are they aligned true to each other?

..if they are, then the control surfaces should 'flop' about easily when you disconnect the control horn /link.

Otherwise.... Perplexed??

The UCD kit comes with the hinge slots already cut, and they seem to be aligned fairly well. The control surfaces all moved freely with no "snapping" action as they passed through neutral.

The CA hinges were installed with Balsa USA thin CA according to the UCD instruction manual, with the exception of widening the gap just enough to allow throws of at least 45 degrees in each direction. The instruction manual suggested a small gap - "just enough to see light through or to slip a piece of paper through". But with the hinges set this tight on my UCD, even 30 degrees of throw became a problem. Could the slightly wider gap have caused the failures?

I take it that this 'Gap' - you mean the one between say - the tailplane and the elevator?

& is the balsa in these areas profiled / chamfered - which allows more movement?

?

Yep, the gap I'm referring to is the distance between the fixed surface and the moveable control surface, (wing to aileron, fin to rudder, stab to elevator). The widest gap might have been 1/16", with 1/32" more typical.

The UCD tail surfaces are double beveled. The ailerons are beveled, but not the trailing edge of the wing. The pre-cut hinge slots were close to the edge of the bevel, but not exactly on the bevel line. The extra gap was needed to get the desired control throws. In fact, I was hoping for more aileron throw, but that would have meant using an excessive gap. (The new hinges will cure that problem.)

On the other hand, I do not expect perfection from an ARF. Even though the hinge slots may have been slightly out of line, and the CA hinges broke, I still consider the U Can Do to be a terrific value!!! I just wish I would have used "doorhinge" style hinges in the first place.

Did you seal the aileron and elevator hinges with a strip of monocote? Wouldn't this help with the problem of "snapping CA hinges? I have been told all control gapps shouls be sealed. Just my .02 worth!!
Bfife

Sealing the gaps might have helped, but I'm not sure.

Unfortunately, sealed gaps didn't prevent CA hinges from breaking on several other planes I've had, so I didn't go to the trouble of sealing the UCD gaps.

However, once all of the new hinges are installed, the gaps will be sealed in hopes of making the controls even more responsive.

Yesterday was the maiden flight of my UCD. After 5 flights I noticed the top rudder CA Hinge had torn in half. I have read Mike Buzzeo's How To column on Installing CA Hinges. I installed the hinges using his method, but the hinge still failled.

The UCD rudder is too large of surface for using CA hinges. I was doing knife edge loops, and many different spins involving Maximum rudder throw in flights 3, 4, and 5.

Has anyone had success using CA hinges on the UCD when doing ratical manuvers involving maximum control surface movement ?

This has been one of the funnest planes I have flown!!! I am just bummed about needing repairs already.

As far as the "Crayon trick" is concerned I'm not sure I believe it actually does anything. Think about it..........thin CA has the consistancy of water. If it can flow 1/2 inch from the center to the outer edge of the hinge, it isn't going to have any problem flowing beneith the crayon mark on the hinge.

Check the pic below

That explains it real well coomarlin.