I flew my 25% H9 CAP 232 w/ OS 1.60FX and 18x6 prop yesterday. Still getting familiar with the plane so I'm not doing much other than simple areobatics, loops, stall turns, split S. About 4 minutes into the third flight I noticed the elevator trim change and the plane started to dive slightly. I gave about 4 clicks of trim to compensate. Elevator response was sluggish, something this plane is not known for, so I knew something was wrong so I made a quick landing. On landing I had barely enough elevator to flare. Upon inspection one elevator half had 2 of the 3 CA hinges fail. They did not pull out they split clean right on the hinge (pivot) line. The balsa structure appears fine and I didn't notice or hear any flutter during the flight. I have a Hitec 5645 metal gear digital servo for each elevator half. The linkage is vitually slop free, straight fiberglass pushrod w/ 4-40 rod. I have only about 15-20 flights on the plane. I have a H9 1.20 UStik with 300+ flights. The CA hinges in my Ustik appear to be the same that came with the CAP. I have abused my USTIK yet all it hinges have survived. I have repaired the elevator half using 5 sig easy hinges. I'm debating if I should cut the hinges on the other elevator half and rehinge that one as well????

Any ideas on the cause???

I all so had the out Side hinge cut in half on the hinge line on my h9 1/4 cap. I replaced the hinge with solid ca hinge mat. Two days later the outside hinge went south on the other side of the elevator. CA hinges will be come very brittle with to much ca applied. I all so think the counter balance on the elevator is put a large strain on the out side hinges. I am putting together a second 1/4 cap, and have installed GP pinned hinges, we will see how that works out. The hinges that ripped on your elevator, were they on the out side as well?

Out the three hinges only the middle hinge was left intact. The inner and outer hinge split.


When I initially assembled the plane the Hangar 9 instructions gave measurements as to the mounting placement for the control horn on the elevator halves. When I used these measurements it placed the control horn off the hinge line. I wonder if this placement is causing added stress to the hinges. Is there a practical reason the horn should be off the hinge line or maybe I measured wrong? Or should I move the horn to the hinge line ??

The inner frame piece of the elevator halves on this model are hardwood; it's what they intend for you to screw the horn to. I thought that was a bit flimsy, so I cut into the covering and added a square piece of hardwood glued into that corner, and covered it with some whit UltraCote.

Now I have lots more "load-bearing" hardwood, if you will, and I was able to position the horns properly over the hinge line. I was a bit wary of those hinges, as they seem to be mostly paper, but used them anyway. I haven't finished nor flown the plane yet (too many other projects to finish first), but I hope my trust in the hinges isn't misplaced...

Steve

I too added a some hardwood in those corners. But I used their mounting instructions and still placed the horn 1/2" back from the hinge line. I thought the offset was possibly there for a reason.

I'm going to remove the horns and line them up with the hinge line, unless someone has a reason I shouldn't.

Amazing, thought i was the only one to have this problem. 5th flight on the Yellow Cap left half of the split elevator come loose, same thing, little elevator control, changed all of mine to pinned.

Did your original CA hinges split in half or pull out ?

One of the veteran pilots in the club says it is the vibration at idle from my engine that probably weakened the CA hinges and caused them to split at the hinge line. Maybe a softmount for my 160FX.

Sta away from ca hinges at least on aircrafts of this size.


epc.

I figured since H9 supplied the CA hinges with the kit they must acceptable to use. Live and learn I guess. :stupid:

Don't be surprised H9 supplies a lot of crap with their kits.

epc.

Ya gotta use FRESH CA. Happened to me before I even flew because I used last year's CA which had thickened slightly and didn't wick in properly. The stuff left on the hinge center was brittle and the hinge broke just from manually flexing it. How was your CA?

I'm pretty sure it was fairly new, but I'm not 100% positive.

I am following this thread keenly coz I am ready to start assembling my H9 CAP-232.

A friend of mine bought the Sig Extra 300XS and replaced all the CA hinges with robart hinges.

While I don't know about 1/4 scale planes and how the stress affects the CA hinges, I can comment on smaller planes.

I had (past tense ) a 40 size Kyosho CAP 232 which I used and abused for 2 years. After about an year, the CA hinges started to fail one-by-one. First the aileron's, then the elevator and then rudder. They would split right in the middle as if they were being cut.

That makes me wonder if CA hinges just have a typical life span ?

Well... adding CA to the hinges isn't a WHOLE lot different from adding it to fiberglass cloth. It gets brittle as you work it back and forth...

I like pinned hinges better myself, but they are heavier (not enough to matter on the planes you guys have).

Of the H9 hardware included with my US60, I'd have to say the gear was fairly good (bent a little wrong at the wheels), the pushrods were STIFF as 4ell, and were difficult to cut. The metal's hardness was MUCH more than the standard metal pushrods I've gotten from LHS. Don't know if this is a good or bad thing. The tailwheel assembly was... garbage. First crash and it's outta there. The fuel tank was woefully undersized for an airplane the H9 guys tout as 'loving with a saito 100'. I figure about 10 mins on a 100? I get about 9 with my .65 2C. The tank's also weak and a pain to install because it's all blind. A longer, tougher tank would solve ALL these problems and cost about $0.02 more to make for H9... The control horns I liked. I appreciate having 3 fastening points. I do have to admit it spreads the load better over the soft balsa my US60 has in the attatch points (I, too have the hardwood cross-member in both the horizontal stab and the elevator itself). The control rod guides inside were mounted nearly in the center of the plane. I can see no reason for this as it just means you have to bend the rods to meet the servo stock positions. To get around this I put a slight kink in the pushrods to relieve 'stall' tension. If I build another I'll just remove the servo bracket and install it in the right place.

I've hardly been building long enough to say "I know it all" but this just seems like an easilly avoidable problem.

Anyhow, you can always use a toothpick to put vasoline down the center of the hinge. It's a pain in the butt but it works. Rub in the vasoline with the edge/tip of the toothpick and the CA wont' flow there. HOWEVER, I DONT KNOW if CA adds to the STRENGTH of the hinge, so check this on some scrap first.

EPC I agree, its not worth it to me to loose a plane because of a litttle extra work with pinned, and yes they split in the center. I think when the CA wicks it weakens them. My 2 cents

i had the same prob with my cap on its first flight, i wasnt so lucky though.. after a few circles on my first flight one aileron cam completely off never to be found again. long story short i lost control and down it came.. upon further inspection, the other aileron was almost completely torn off as well.. only a matter of time.. i definately will use a different hinge system on my next cap.. i was lucky and got a free replacement after sending them the defective parts

I have to say, compared to most ARF manufactures, H9 hardware at least with Ultra Stick 120, Cap 232 1/4 is of very good quality. No I didn't use the supplied fuel tank, pull-pull, or tail wheel but over all the rest of the hardware is good. As far as CA hings on a plane of this size, I'm not sure they should be used.

I can tell you the hardware that H9 offers for there 1/3 Cap is of very good quality.

Doug

When I had a CA hinge failure it was becasue of the hinges being off a little or maybe the elevator was a little crooked and all of the outside hinges broke in same manor as yall are discussing. When I get hinge line perfectly straight, guess what, No failure since..... Just make sur ehat you aren't putting the hinge in a bind and it should be ok. Oh yeah use the elec hinge tool, creates perfect holes for ya.

Gastronom, hinge line was perfect, no bind, used electric slot machine, 2 drops CA, still split down the center. Darn the luck.

Ouch, sorry that expelled my thoughts about it. I still use them but i do so on the .40- sized aircraft...

I have been flying my Cap since 12/10/01 and have about 100 flights on it. So far so good. It only takes about 3 drops per side on the C/A thing. Too much and like in the earlier posting says... damming of the C/A at the hinge line will cause a bind against the hinge when that surface is deflected against the built up C/A.
One way to relieve that problem is to cut a little of the film away from the hinge line exposing the wood where the hinge is inserted. This seems to work best for me.