CopterX 500 / HK 500 CMT tail rotor grip failing in flight
#1
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CopterX 500 / HK 500 CMT tail rotor grip failing in flight
Is this a common problem?
It happened to me twice now, one for each of the mentioned models. Both had alloy blade grips.
Both incidents ended in a horrible crash.
The problem seems to be the screw which the blade grip pivots around.
It had snapped clean off in both failures.
Both failures happened mid flight during hard manouvering with the tail rotor.
Does the align stock parts fair any better?
It happened to me twice now, one for each of the mentioned models. Both had alloy blade grips.
Both incidents ended in a horrible crash.
The problem seems to be the screw which the blade grip pivots around.
It had snapped clean off in both failures.
Both failures happened mid flight during hard manouvering with the tail rotor.
Does the align stock parts fair any better?
#2
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
The same thing happened for me just now.
Flying in a hammerhead manouver, right at the apex of the hammerhead, where I agressively flip the tail 180 degrees, the screw securing one of the tail rotor grips snapped clean off, resulting in a disasterous crash.
This time as well as the previous times, I were using alloy blade grips.
Is nobody else experiencing this on HK 500 or CopterX 500?
If someone else has been troubled with this, how did you solve it?
Flying in a hammerhead manouver, right at the apex of the hammerhead, where I agressively flip the tail 180 degrees, the screw securing one of the tail rotor grips snapped clean off, resulting in a disasterous crash.
This time as well as the previous times, I were using alloy blade grips.
Is nobody else experiencing this on HK 500 or CopterX 500?
If someone else has been troubled with this, how did you solve it?
#3
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
If I`m not mistaken (that it is you) you had said you prefer the belt over the torque tube cause you can chop trees and still the belt is OK, than a stripped gear(s).
Maybe the belt is OKbut something else may have bent or got some big slop. This stress the tail grip as the balance is not OK. Check the tail blades also.
And maybe you should change the screws you`re using with some other better quality, although the problem is not at the screws themselves.
Except there is a common problem to this model, that Ican`t know.
Maybe the belt is OKbut something else may have bent or got some big slop. This stress the tail grip as the balance is not OK. Check the tail blades also.
And maybe you should change the screws you`re using with some other better quality, although the problem is not at the screws themselves.
Except there is a common problem to this model, that Ican`t know.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
Every tail problem I ever encountered was caused by a bent tail shaft or bad bearings. I have never lost my HK500CMT or my HK500GT due to tail problems, but I have had numerous problems with my 450 helicopters, including a name brand KDS450.
I wish you luck in figuring this problem out, and please post your findings.
Thanks,
Bryan
I wish you luck in figuring this problem out, and please post your findings.
Thanks,
Bryan
#5
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
Screws and blade grips, bearings and shaft are all brand new. I swapped the whole assembly after last crash.
Still the problem persists.
Still the problem persists.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
1 question did you replace with align parts or did you put in the junky clone bolts ? i have had to many exi bolts break just tightning and or loosening em up i would start there. just my.02
#7
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
Thanks madmorgan.
The parts are original HK500GT parts
I didn't want to waste my money on western resellers before I actually knew Align stock parts are any better on this point.
I tested it now with replaced bolts. So far so good. But the stock ones didn't break first flight either, it was after 8-10 flights. So lets see how it goes.
The parts are original HK500GT parts
I didn't want to waste my money on western resellers before I actually knew Align stock parts are any better on this point.
I tested it now with replaced bolts. So far so good. But the stock ones didn't break first flight either, it was after 8-10 flights. So lets see how it goes.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
biggest problems i found with the clone bolts is putting to much muscle into the bolt , this is where snug and let the thread lock work is useful but i have had way to many problems so i just get the align hardware. also i note the metal in general is really soft, stripped alot of threads out on tail plates (exi 30 dollar head and tail) also i had a exi 250 jesus bolt break (ended up replcing head block) when trying to remove for main replacement. clone parts prices are hard to beat but it saves money in the long run to replace broken , bent clone parts with align imho.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
Those hk tail blade grips and bolts do this often. If the bolts dont break in half they will usualy try and back out. At times with any bolt threaded into these hk tail blade grips... The best solution is to just buy the cheaper align plastic tail blade grips. ( $12 usd )
#11
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
Morgan: I replaced the tail bolts with some generic machine screws. So far they are holding up well. Better than the chinascrews anyway.
How they compare with Align stock parts I wouldn't know.
The tail of the HK-500GT is a well knows problem (plastic blade grips), I think it should be added to the story that you should not just replace to alloy blade grips, but replace the screws aswell.
Thanks for the tips guys =)
Barbie: the bolts unscrewing wasn't the problem I had.
The bolts were secured with threadlock and they were definetly broken In half, as the other half was still properly secured with threadlock into its hole, after the failure.
How they compare with Align stock parts I wouldn't know.
The tail of the HK-500GT is a well knows problem (plastic blade grips), I think it should be added to the story that you should not just replace to alloy blade grips, but replace the screws aswell.
Thanks for the tips guys =)
Barbie: the bolts unscrewing wasn't the problem I had.
The bolts were secured with threadlock and they were definetly broken In half, as the other half was still properly secured with threadlock into its hole, after the failure.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
thats good news , i have had nothing but problems with the exi bolts, i also got the cf alumi blade 400 aftermarket frame and they were all junk too.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
this are common even with the align helis. we had a couple of this screw breakage with the Align 700N and a 600E the screws just breaks leaving only the tail hub with a bent tail shaft.. What was seen was the screws on these tails when over tighten usually have hairline cracks..that as time progress and extreme moves fractures and breaks the screws resulting on a flying tail blade...
its good to use loctite but do not over tighten the tail screw. this mostlikely caused the bolts to fracture and fail when loaded
its good to use loctite but do not over tighten the tail screw. this mostlikely caused the bolts to fracture and fail when loaded
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
I find it funny that you all are talking about this. I had the same exact problem on my 450 Pro. I had the EXI blade grips on it and the bolt snapped on me. I was lucky and was able to get it down safely. I switched to the RC Aerodyne Chaos 450 tail blade grips and haven't had any problems since. Funny on how I thought it was a rare occasion, but apparently not so rare after all.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
I made the same mistake a few years back when I had the blade 400. What a waste of money that was.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
yeah you know thats right solman the flippin boom doesnt hold well in the mounts and all the bolts are extremely soft and junky! reffering ofcourse to the aftermarket b400 aftermarket. but im still flying mine ofcourse the head and tail are align lol
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
It wouldn't have been so bad if they made the tail boom holder one solid piece instead of too. I actually crushed a boom tryin to make it tight enough so it wouldn't move.
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RE: CopterX 500 / HK 500 CMT tail rotor grip failing in flight
all i did to reedy it was i have a boom that suffered in a wreck i take off about 1 /12 inch peice slit it down the middle and make it so it fits exactly inside the new boom put in a touch of ca glue so it stays and it doesnt crush it holds nice.