RunRyder RC
 10  Topic Subscribe
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 1677 views POST REPLY
HelicopterGasser Model RC HelicoptersOther › in air tail boom failure
01-15-2011 02:28 AM  7 years agoPost 1
mrford

rrApprentice

elmwood park nj usa

My Posts: All  Forum  Topic

I have a helibug trex 700 with a zen 27 rc its 2 months old with about 1 gallon through it i do not do 3d i fly slowly and very controlled . Last week the tail boom broke 1/8 inch in side the plastic block in the frame.It was the carbon fiber over aluminum align boom this happened in the air witnessed by my flying buddies . I built this ship I used locktite where appropriate .It looks like it fatigued and cracked in flight . I changed the boom to the all aluminum one from align maybe the aluminum is thicker than the fiber over aluminum one.Is there eny one that has experienced this failure is this common is there a fix ? I think i am going to make a sleeve and locktite it inside the boom tube at the heli end so it cant crack ?I would really like some feed back . if i sleeve it i will let you know how to do it and how it goes . Wondering if this a gasser problem extra vibration from the engine maybe?

PM  EMAIL  Attn:RR  Quote
01-15-2011 02:49 AM  7 years agoPost 2
Santiago P

rrProfessor

South West, Ohio

My Posts: All  Forum  Topic

Please don't take this the wrong way.

BUT

Do you realized the type of vibration a large engine produces?

The TRex 700 was designed to be a ultra light, all out 3D machine (not that well IMO)

Purposely designed gassers are rugedize in the right places to take the higher amplitude, lower range vibrations of a large gas engine. Most are built like tanks.

Maybe your boom had a flaw to begin with.

BTW, that is not real carbon on the boom, but a carbon finish look.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-15-2011 04:03 AM  7 years agoPost 3
Justin Stuart (RIP)

rrMaster

Plano, Texas

My Posts: All  Forum  Topic

Does Align make a real carbon boom for the 700?

Avant RC
Scorpion Power Systems
Thunder Power RC
Kontronik Drives

PM  EMAIL  GALLERY  Attn:RR  Quote
01-15-2011 04:51 AM  7 years agoPost 4
rbort

rrProfessor

Franklin, MA - USA

My Posts: All  Forum  Topic

+1 on that last post
The 700 was not meant to be a gasser. Yes you can put a gasser motor into it and fly it, however, some parts may fail more often due to this because they were not spec'd out for a gasser to begin with.

To give you an example, nitro machines on one particular brand that I'm familiar with use frames that are 78 to 80 thousands thing. A gasser machine of this same brand uses frames that are 90 to 32 thousands thick.

In general YES things need to be beefier on gas machines to withstand the power and torque of the gas engines.

-=>Raja,

MA 1005 Hanson 280, 4187 flts
Spectra 27 3DMax, 3252 flts
Whiplash V1-2 Hanson 300, 1503 flts
Whiplash V2 Hanson 300, 353 flts

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-15-2011 11:19 AM  7 years agoPost 5
shawmcky

rrElite Veteran

Isle of Wight,United Kingdom

My Posts: All  Forum  Topic

Would that be a stock 27 motor?Did you check hub runout.Vibe levels do need to be kept at a minimum,which means the set up has to be the best it can be in all areas,alignment,tuning, curves, ect.

Team- unbiased opinion.K.I.S.S principle upheld here

PM  EMAIL  GALLERY  Attn:RR  Quote
01-15-2011 05:33 PM  7 years agoPost 6
smallplanes

rrElite Veteran

S.C. ,SSA

My Posts: All  Forum  Topic

Now i know i'm not going to convert my 700 to gas. Sorry to hear your problems.

Thanks
smallplanes


Spectra G 26cc
Jewel
Bat 27cc
Trex 700<br

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-15-2011 11:25 PM  7 years agoPost 7
Santiago P

rrProfessor

South West, Ohio

My Posts: All  Forum  Topic

Now i know i'm not going to convert my 700 to gas. Sorry to hear your problems.
I would not unless someone makes a comprehensive kit that beef ups the frames, booms, and other crtitical areas. IMO you are better off buying a used Bergen, XCell, or Century gasser.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-16-2011 12:13 AM  7 years agoPost 8
smallplanes

rrElite Veteran

S.C. ,SSA

My Posts: All  Forum  Topic

I know your right.

Thanks
smallplanes


Spectra G 26cc
Jewel
Bat 27cc
Trex 700<br

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
01-16-2011 12:22 AM  7 years agoPost 9
mrford

rrApprentice

elmwood park nj usa

My Posts: All  Forum  Topic

The helibug kit is very well made they provide new very thick frames and bace plate even heavy tail fins you. Use only the cross peaces and gear boxes . But you use the align tail boom when. I built this kit align provides 2 booms one is rapped in what looks like carbon fiber i think the aluminum is thiner i think i will put a 3 inch sleeve inside the new all aluminum boom witch i think is thicker the sleeve will stop the hidden breakage and put it out in the open and wont show .I can look dearing pre flight if it shows a sine of cracking i can change it out .I will look for eney runout or eney extra vibration creating problems .I think using the "lighter" and cooler looking boom was a mistake . This should not be an impossible fix this ship is not a money pit . this is the only problem i have had in maybe 5 hours of flight time please don't condemn a very well thought out kit that fits well and flies well .Don't use the "carbon like boom" i will look carefully at this point at pre flight i love this ship .Eney other ideas would be appreciated thanks for your help.

PM  EMAIL  Attn:RR  Quote
01-16-2011 12:31 AM  7 years agoPost 10
Justin Stuart (RIP)

rrMaster

Plano, Texas

My Posts: All  Forum  Topic

Is the CF boom even covered in carbon fiber, or is it just plastic of some kind?

Avant RC
Scorpion Power Systems
Thunder Power RC
Kontronik Drives

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 02:17 AM  7 years agoPost 11
mrford

rrApprentice

elmwood park nj usa

My Posts: All  Forum  Topic

I have the broken peaces it is in fact very thin carbon fiber but the aluminum is very thin . The all aluminum seams thicker over all. Sunday afternoon i will measure it .I think the carbon dose not add strength it cuts weight for 3d .The carbon is real thin so is the aluminum i think its over all weight is less . It may be stiffer but not stronger .

PM  EMAIL  Attn:RR  Quote
01-16-2011 03:08 AM  7 years agoPost 12
Rototerrier

rrVeteran

Fayetteville, GA - USA

My Posts: All  Forum  Topic

The TREX 700 has historically been a piece. Sounds to me like just more of the same. I suppose you can be somewhat thankful that your head bolts didn't shear, tail grips didn't fly off, links didn't break, gear didn't strip, torque tube didn't split, jesus bolt didn't snap, main align blades didn't separate, or the tail blades didn't separate at the root. Could have been worse

Gassers Rule, Nitros Drool, Electrics...uhhh...Joule?

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 03:45 AM  7 years agoPost 13
CNCjunkie

rrVeteran

Kauai (The Garden Isle), Hawaii - USA

My Posts: All  Forum  Topic

Hey guys, I have an idea.

Instead of all the negative posts about any products, how about we give some constuctive ideas to help to solve the issue, which is most likely caused by excessive vibration. Like any gasser, correction, any heli on the market, you're going to have mechanical failures with excessive vibes present. That's were I would start mrford.

Dial the clutch, make sure the drive train alignment is true, blades are balanced, main and tail and tracking correctly, torque tube straight and true. etc., etc. Once you know all the basics are covered, then start suspecting the engine mechanical or tuning.

How does your tail control pushrod look right after the tail control arm mounted at the back of the frame? If it buzzes like a guitar sting you have too many vibes. Tail fins buzzing? To many vibes. Foam in the tank? Too many vibes. Skids look blurry? To many vibes. I could go on and on...

Just another crappy day in Paradise....Aloha!

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 09:41 AM  7 years agoPost 14
shawmcky

rrElite Veteran

Isle of Wight,United Kingdom

My Posts: All  Forum  Topic

^^^+1 on that,be careful of getting into a "i love this product"and I hate that product fight,or,"I am just stirring for the hell of it"type of comment.Many fly all types of helicopters,some cant even get a "reliable"purpose built gasser in the air and it has nothing to do with the helicopter.Constructive criticism through experience with the product is the best way to go.Hope you get your tail boom problem sorted and i am sure genuine owners and flyers will give you some tips.As stated all excessive vibes are your enemy no matter what you fly.

Team- unbiased opinion.K.I.S.S principle upheld here

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 12:44 PM  7 years agoPost 15
Rototerrier

rrVeteran

Fayetteville, GA - USA

My Posts: All  Forum  Topic

I hope I didn't offend anyone with my comment. I was actually making an indirect point that it isn't necessarily fair to blame this failure 100% on the gasser conversion when trex 700's have been falling apart since the first day they were released. I may have been a bit too indirect and I appologize for that.

To be helpful, you might want to add some cross braces on the boom supports. Align now sells some nice ones. I copied some of the other home brew methods and cut an old torquetube into little sections and made 3 braces. Not that this will eliminate vibrations, but it could secure the boom a bit better and keep it from moving as much and leading to a failure. Just a thought.

Gassers Rule, Nitros Drool, Electrics...uhhh...Joule?

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 01:41 PM  7 years agoPost 16
mrford

rrApprentice

elmwood park nj usa

My Posts: All  Forum  Topic

I appreciate the good input . I am a mechanical kind of guy and this is a problem that can be solved .The align bolts are very soft its a shame align could make or buy better bolts.5 or 10 dollars more would not deter sales . I will remove the motor and indicate the clutch. I need to super track the blades I wonder if i should put the 2 blade spacers on the top of the blades ??? There is no buzz of tail fins i put an extra control rod guide and put 2 support rod holders . I realize that modifying anything causes problems . These can be solved .I do not take affiance at people giving honest thoughts .I thank my hobby buddies for taking the time to think and to post possible fixes .We need to stand together to support our hobby thank you all .

PM  EMAIL  Attn:RR  Quote
01-16-2011 02:39 PM  7 years agoPost 17
fastflyer20

rrKey Veteran

N. Tonawanda, NY

My Posts: All  Forum  Topic

A nice support like the pic below may help. I did sleeve my B400 boom back in the day. I cut a section a few inches long from a scrap boom and split it length wise then increased the slot so the insert could slide inside the full size boom. A bit of epoxy secured it all together. It dramatically increased the strength.

https://rc.runryder.com/helicopter/rr/mygallery.htm

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 06:50 PM  7 years agoPost 18
mrford

rrApprentice

elmwood park nj usa

My Posts: All  Forum  Topic

Wow thats a good idea i knew some one would have a solution its simple and cheep and will probably work thanks I will try it tomorrow I like it a lot . I have 2 rod supports one I made the other is store bought I like the one you have pictured I will ask my local hobby guy.

PM  EMAIL  Attn:RR  Quote
01-16-2011 10:19 PM  7 years agoPost 19
oldfart

rrProfessor

Vancouver, Canada

My Posts: All  Forum  Topic

An X-support for the boom struts such as this really does stiffen the support structure a treat. I first came across it when I assembles my first Predator a number of years ago. They were included with the kit.

Phil

PM  EMAIL  GALLERY  Attn:RR  Quote
01-16-2011 10:33 PM  7 years agoPost 20
SeismicCWave

rrVeteran

Hilo, Hawaii

My Posts: All  Forum  Topic

Another work around will be to source out a tail boom with similar O.D. but thicker wall. I believe the Bergen gasser boom is similar O.D. and has a very thick wall. The O.D. is 7/8" which is a shade over 22 mm. The Trex 700 boom is also a shade over 22 mm.

A tail boom support cross tie is a good idea to get rid of the resonance and so is the support on the tail pushrod but they also mask the symptom.

The main enemy of the gasser is the high frequency vibration from the engine. Definitely try to eliminate as much of that as possible. You can't get rid of all of the vibration because the engine has to run to give you power. Single cylinder engine will always vibrate a bit. So do the best you can.

PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 1677 views POST REPLY
HelicopterGasser Model RC HelicoptersOther › in air tail boom failure
 Print TOPIC  Make Suggestion 

 10  Topic Subscribe

Tuesday, April 24 - 6:00 am - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online