START HERE |
|
Register | FAQ | PM | Events | Groups | Blogs | Calendar | Mark Forums Read |
Unregistered
|
500 Class Electric Helicopters 500 Class Electric Helicopters manufactured by Align, Tarot, SYMA, Airhog, Chaos, HK and similar. |
|
LinkBack | Thread Tools | Display Modes |
03-20-2012, 04:18 AM | #21 (permalink) |
Registered Users
Join Date: Aug 2010
|
All of the bolts that failed on my 500 were 12.9 (RTL, McMaster, and a milspec).
__________________
"The problem with quotes found on the internet is you have no way of confirming their authenticity." - Abraham Lincoln |
Sponsored Links | |||
Advertisement |
|
03-20-2012, 06:20 AM | #22 (permalink) |
Registered Users
Thread Starter
Join Date: Feb 2008
|
again thanks again to all for the opinions, I do have to disagree with overtightening (for my case ONLY) because I personally know how loose those bolts were
I will never use the 2mm bolt design again, I know when something doesn't seem right and won't be taking the chance I guess we really need a 3mm spec for this thing's tail, or the kasama-type design seems to be a good idea too - thing is, what would fit the 500..? any ideas, anyone at all? best Fly
__________________
Futaba T7C & T14SG, Trex 450 SE V2, HK500GT, Trex600, Trex 600L Dominator, Trex 800 Trekker Beautiful Birds, Idiot Pilot! woohoo! |
03-20-2012, 09:19 AM | #23 (permalink) |
Registered Users
|
Fly, first of all, l'm just trying to understand the actual problem and I am in no way having a go at you...... I just wish I could help you more to solve your problem.
Anyway .................... You say you have a HK500 GT which you have tried to turn into an Align product by upgrading those clone HK parts with genuine Align products ? The first bolts to shear you said was when it was stock ..... which means it was not Align products that first failed. The reason I upgraded to the Align parts was that the original tail holder bolts sheared off on maiden flight before take-off was achieved. You then replaced the tail with an Align product...... Bolts have subsequently failed .... so if all the bolts are failing on a non align product and on an align product .. what is left ? ..... 2 things. 1. The person putting them together 2. The tail blades them selves Take your pick ..... sorry mate but I still sway on the side of your probably doing something not quite right .. but .. only you can work out what. As for the comment .... anyway, in my opinion, the tail design does not support the side-to-side (lateral) movement of the blades, the carbons are very stiff too and probably transfer all that force right to the root - therefore flexing the holder which in turn, bends the bolt back and forth until fatigue occurs and it shears The tail blades should have a brass insert (bushing) and when the tail blade is fitted into the tail holder, the blade side walls should be snug up against the inner walls of the tail holder. This eliminates the sideways play (slop) The bolt should also be snug inside the brass bush....... This is to make sure the blade does not “rattle” about the bushing. If the blades are too loose in a "holder" then the forces generated within the tail will be transfered to the bolt and snapped bolts could result., especially on large rudder pitch changes. The weakest part of the bolt being the part where the shoulder stops and the thread starts. I note in your diagnosis .... I can tell you I was more worried they would spin out they were so loosely put in Just for the record, I have a full Align 500e Pro and the tail blades and tail holder do not have any play at all, all parts are machined perfect. Saying that this is all down to badly machined parts and telling us that Align products dont work is far from being correct. I wonder why people buy full align products in the first place ? For what its worth..... If I was you ... I would try new align tail blades in a new Align tail rotor holder, then take it from there. Let us know how you get on and what road you go down .... best of luck nbells |
04-03-2012, 05:24 PM | #25 (permalink) |
Registered Users
Thread Starter
Join Date: Feb 2008
|
so,all the bolt failures in this thread PLUS the fails here:
https://www.helifreak.com/showthread.php?p=1958566 means the product is great and I'm a unique idiot? not sure I take kindly to that... for the LAST time the tail was a COMPLETE ALIGN PRO UNIT, the bolts still snapped, and I think the answer is in the same thread near the end: https://www.helifreak.com/showthread.php?p=1958566 PROBLEM: it seems my motor (turnigy typhoon 1800Kv -- a beast that actually turns more like 1900-1950Kv) should be on 5S -- it's on 6S, my pinion is 12T (11T now on the way) and a 12T at more than 85% throttle is death for the bolts due to nothing more than centrifugal force at that massive headspeed SOLUTION (hopefully): 11T pinion new complete Microheli tail unit KBDD superlight tail blades to keep weight off the bolts I believe the diagnosis is correct 'cos this heli's 2nd test flight was a great success - I had the throttle limited to 85% flat fail 1: during assembly one of the bolts sheared just while loosening it to put locktite on - it was loose before I started - not align product though fail 2: 1st test flight the bolts sheared while it was still spinning up, but they were not align product at that point fail 3: 3rd flight I had ramped the curve back up to 95%, the bolts lasted about 2 minutes in gentle flight... they were ALIGN and supplied with the PRO tail never mind, I will stick with this solution and test it and let you know, it will take some time as some of the lesser broken parts are being replaced from HK OK OK Align I still love ya :-) but PLEASE check these bolts again? I have read other posts where people are getting HIGH headspeeds with this heli and NO tail problems so have I got part of a bad batch or something...? cheers Fly
__________________
Futaba T7C & T14SG, Trex 450 SE V2, HK500GT, Trex600, Trex 600L Dominator, Trex 800 Trekker Beautiful Birds, Idiot Pilot! woohoo! Last edited by flydude; 04-03-2012 at 05:27 PM.. Reason: cos i can |
04-03-2012, 07:31 PM | #26 (permalink) |
Registered Users
Join Date: Apr 2011
|
been through a few sets of those bolts. never had one break, just replaced during maintenance. I would imagine vibs could also maybe cause these to break.
__________________
USMC - EXPEDITIONARY AIRFIELDS - MCAS MIRAMAR Align Trex 500 Scorpion 3226-1400 powered missile |
04-06-2012, 09:27 AM | #27 (permalink) |
Registered Users
Thread Starter
Join Date: Feb 2008
|
I guess the next question to ask is if anyone uses a 500 class heli with the Turnigy Typhoon 1800Kv motor ON 6S Lipo AND 12T pinion -- and has had the same problems, or at least, if they have found the headspeed to be too high..?
thanks folks! the microheli tail has arrived and looks good - more results when the other parts get here - right now I'm gonna tidy up my 450 for summer, back to the 500 asap tho best fly
__________________
Futaba T7C & T14SG, Trex 450 SE V2, HK500GT, Trex600, Trex 600L Dominator, Trex 800 Trekker Beautiful Birds, Idiot Pilot! woohoo! |
04-06-2012, 01:50 PM | #28 (permalink) |
Registered Users
Join Date: Jun 2010
|
I am running the same Typhoon motor at 90% on my 500 on a 13T pinion without any bolt issues so far. Small amount of loctite on lightly snugged bolts. 25 flights, no problems.
__________________
ZMR250, DYS 1806/2400KVS, HK Blue Series 12a ESC, 3s/2200, DAL 5040, 400mW VTx, 3dr telemetry, MinumOSD, miniAPM 3.2.1 FC w/GPS, OrangeRx R720X, 700TVL FPV cam, RuncamHD |
04-07-2012, 08:30 AM | #29 (permalink) |
Registered Users
Thread Starter
Join Date: Feb 2008
|
Ferrett thanks for the reply - I also need to ask, is yours the tail belt drive or torque tube version and would you know if there is any difference in the drive ratios between the two?
NB: are you running yours on a 5S or 6S battery? (Volts & Amps?) What type of tail unit is it (is the gearbox and grips metal or plastic?) and what brand/type of tail blades do you have? cheers mate Fly
__________________
Futaba T7C & T14SG, Trex 450 SE V2, HK500GT, Trex600, Trex 600L Dominator, Trex 800 Trekker Beautiful Birds, Idiot Pilot! woohoo! Last edited by flydude; 04-07-2012 at 09:46 AM.. |
04-23-2012, 09:24 PM | #30 (permalink) |
Registered Users
Join Date: Jan 2011
Location: Sao Paulo, Brazil
|
My trex 500 had a tail explosion last Sunday due to a broken bolt. Now I'm worried, maybe the 2mm bolt is too weak for the job.
I'm considering replacing these bolts once a month to avoid they break again due to fatigue. Cheers!
__________________
Compass 7HV / Atom 6HVU / Atom 5.5 / Align Trex 500L / Spektrum DX8 Not flying anything - model or full - since 2017! |
04-24-2012, 10:01 AM | #31 (permalink) |
Registered Users
Join Date: Jun 2009
|
Tail Rotor Designs
Here's a little food for thought about tail rotor designs.
http://www.i2rc.com/forums/showthread.php?tid=9
__________________
HK Best Of Custom 450s & 500 Build Different! |
04-24-2012, 04:27 PM | #32 (permalink) |
Registered Users
Join Date: Dec 2010
|
I've had my 500 for just a year, never had a bolt failure, all the talk about this caused me to by a Kasama hub and it flew until I had a buzz/vibe I couldn't shake, replaced, the gearbox, output shaft, installed a 500 pro hub, new blades, finally turned out i was overtightening the boom clamp that holds the vertical fin on. Never got around to rebuilding the Kasama hub as the pro seems just fine.
Whenever I regreased the thrust bearings, I replace the bolts, they are McMaster 12.9 Cheers. PS the day I2 makes a TT driven tail rotor, I will be all over it. I think their tr hubs are using a bigger tail ds to accomodate the pitch change shaft thru the drive shaft design. So no other mfg make a hub that will work on a Trex 500 ? ( don't bring up micro heli )
__________________
T-rex 500FBL BeastX, I2 MRH & Swash, I2 boom support,( Bob's the Mahn ! ) DX7s. T-rex 550 I2 FBL head & boom support,KDE motor mount. CH-53E's 83-87. MCAS New River. FAA certified Airframe & Powerplant license holder since 1992 |
04-25-2012, 12:50 AM | #33 (permalink) |
Registered Users
Join Date: Sep 2007
|
It is possible to change the thread to 3mm and instead of a bolt to add a self locking nut and an extra ball bearing. With the self locking nut you have 100% control af the tension on the thrust bearings.
http://perweb.dk/HaleMod500/Index.htm This mod if done correctly and if you ballance both the hub and the blades also get rid of any vibration from the tail. BTW: With this mod the bolt will NEVER snap again. |
05-27-2012, 05:07 PM | #34 (permalink) |
Registered Users
|
I have had the same issue. Three different tail assemblies and three sheered bolts. Last one was today on new tail assembly on the 8th flight. I to make sure not to over tighten. I have a few unusable hubs with bolts stuck in them, so i might try the 3mm bolt mod.
I wanted to get the Kasama tail, but it seems nobody is selling it. Can anyone find one? I think the issue is due to vibration not necessarily to do with the tail. I spent 5 months trying to find a tail issue on a 450. Tried and replaced everything, until finally i changed the carbon boom to aluminium and Voila vibrations gone.
__________________
Goblin 420 Ikon Compass Warp 360 Ikon RCHN# 229 |
05-27-2012, 08:07 PM | #35 (permalink) |
Registered Users
Join Date: Dec 2011
|
Over tightened bolts...simple as that. Did it just this weekend dumbass me
__________________
☆☆☆AMA #1039539 |
03-09-2014, 03:33 AM | #36 (permalink) |
Registered Users
Join Date: Dec 2007
|
I've had this problem three times now this has to be an Align fault my heli is a stck 500esp blade holder is metal with all Align parts so what is this solution I'm not over tightening the bolts yet they still snap !!!!! Really annoyed as this costs money to repair through no fault of my own !!
|
03-09-2014, 11:18 AM | #37 (permalink) |
Registered Users
Join Date: Aug 2011
|
+ 1 on the overtightening.
Tail has tipically the highest levels of vibes in the heli. If the bolt is extra tight, with its natural elasticity all stretched out, the centifugal forces+ vibes will fatigue it. I never had any of these issues, even when adding Eflite chinese weights. Any way, this bolt should be stronger, for high HS peace of mind. That's two (of many things) i like on the Warp: 2,5mm on tail grips& 3mm on mains, talk about bomb-proof designs.
__________________
XL Power 520(soon to become a 480), Warp 360 , Tarot 360Sport, Logo480 LowRpm , Logo 500 T500 AP |
03-11-2014, 05:09 PM | #38 (permalink) |
Registered Users
Join Date: Jun 2011
|
I had an idea a while back, don't know if it is worth it or not though. I bought some tubing with a 4mm inside diameter and 5mm outside diameter, and it fits perfectly on the shaft. I was thinking I could use 550 tail grips on it, but would the extra gyroscopic force from the extra weight (20.5 grams vs 34 grams) snap the tail shaft?
__________________
Team Synergy |
03-12-2014, 07:35 AM | #39 (permalink) | |
Registered Users
Join Date: Aug 2011
|
Quote:
On the other hand it would get more sensitive to any minimum tail shaft bent, sometimes even brand new there is a tiny bend that messes with the tail.
__________________
XL Power 520(soon to become a 480), Warp 360 , Tarot 360Sport, Logo480 LowRpm , Logo 500 T500 AP |
|
Tags |
bolt, holder, trex500 |
Thread Tools | |
Display Modes | |
|
|