rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 765 ONLINE 19 EVENTS SEARCH REGISTER  START HERE
 
1 page909 viewsPOST REPLY
Revolution Models . CarbonXtreme . Midland Helicopters

.
.
e-Align T-REX 250-450-500-600 > T-REX 600 600 / H500 Funkey scale builds blow up
 
 
Stet
Elite Veteran
Location: Long Beach CA

First off, I am not the type to bash mfr's, and that is not the point here. I am just posting because I am looking for input and your experience / suggestions.

Buddy #1

Builds electric Trex 600 into align funkey fuse. Spools up smooth, suddenly after liftoff goes into resonance and frags the doghouse, hit throttle hold, land it and assess the damage. I find that he left the two bolts out of the rear frame to bottom plate, and did not extend the interior fuse frame (upside down "U" to hold the top of the carbon frame (electric is shorter than the nitro for which the fuse was made). So I figured the guy left too much too loose, told him to tighten it up and extend the interior frame to meet the mechanics frame.

Buddy #2

Buys the same fuse, asks my other buddy to build it. This time we build really nice plate to adapt the electric and build upper support. Spool it up and whack, it goes into resonance and does minor damage. Throttle hold hit before anything broke, just minor damage to the edge of the doghouse where the head goes through. I figure must be the high default headspeed and plan to change pinions and slow it down to 1800

Buddy #3

He tells me the problem is that it is designed for the nitro and so he buys the fuse and puts a 600N into it. He does everything right. Heli was flying nice before the install. We spool it up and tail is vibrating, so we try changing the speed. Was about 1750, go to lift off the ground and WHACK, it goes into resonance. Frags the doghouse, breaks the washout mixing arm and after futher inspection we find it has broken the main frame plate in the fuselage in a umber of places. He's bummed and scraps the fuse.


My perspective is that it seem the fuse frame is just too flexible. I know others have built these and flown them ok, but after seeing these three blow up, I am not so sure. This is why I much prefer the Thunder Tiger design, mounted to the really stiff landing gear. This is also why I do not involve myself with friends' large scale projects.

Has anyone else seen this happen? Does anyone have a suggestion? Buddy #2 expects me to fix his so it flies perfect. I don't really want to deal with it, bt will have to give it my best effort.

keepin' it real
07-02-2008 07:15 AM
 
 
steph280
Key Veteran
Location: Irvine, California

I've had similar experiences with Funkey fuselages (not the H500 though), not just with Align mechanics, but just about any other I've tried. Sometimes changing the headspeed, tighten/losen the blades, or something silly like flying without the scale horizontal stabs will reduce or eliminate the vibration. I guess it has something to do with resonance induced by the fuselage. They tend to amplify the slight vibrations in the heli which we don't see without the fuselage. In fact I am still working on eliminating the shakes on a funkey Airwolf.

Found some interesting tips and success stories over at the tresforum. You might want to browse there for some ideas.

http://www.thetrexforums.com/?board=48.0
07-02-2008 07:12 PM
 
 
gadgetdude
Senior Heliman
Location: Southern California

Stet,
First off, I think this post would be better off in the 'Scale' section as you would get more responses.

Secondly, I am sorry to hear of all the problems, yet I am overjoyed it is not just ME!

I bought the Align/Funkey Fuselage MD500E (yellow). I mounted a Trex 600E into the fuse and did the modifications needed to fit the E vs the nitro. Raised the back plate, secured to the original screws. Built a plate for the front two mounting screws. I adapted the top mounts on the dog house and all was very secure.

I took it out to test fly it. All worked pretty good. Flew it for about 5 minutes. Figure eights, simple stuff, etc. Noticed a slight vibration in landing skids and tail rudder. Took it home and tightened things up so see if it was a loose screw somewhere. Could not find and 'loose fittings'.

Went out a couple days later to fly. Spooled it up and got it about 20 ft high. All of a sudden I got a major vibration in the whole body. The next thing that happens is the horizontal fin on the rear came off and fell into my rear blades cutting it in many pieces. This must have set the gyro off because the next thing I knew was it was pretty much out of control. The vibration was horrible and all I was doing was trying to get it to land. I started to pitch left then it nosed up and over heading strait at me. I tried to regain control but it ended up going nose first into the ground.

Busted the battery. The front canopy broken is several different pieces including the two bottom 'foot' window were torn in several different places. Dog house had some chunks taken out along with have the blades shattered. The bottom wooden mount tore out of the one rear hole and both of the upper mounts had broken away from the fuse.

Replacement parts from Century were going to run me $160. I could buy a whole new 'unpainted' one for $169. I decided to to the repairs my self. I have re finished the rear fin and started the fiberglass repair last night on the canopy.

The real interesting thing that after reading your experiences, is the upper dog house mounts. Both mine had clean breaks from the fuse. Meaning that they were both still attached to the Trex frame but pulled away from the fuse itself. I initially thought that the impact tore them away. Now I am thinking that they may have come detached from the fuse and is what caused the violent vibration all of a sudden. It would also explain some of the 'control' or lack of control of the pitch and roll I was experiencing when the vibration started.

If the brackets did come loose from the fuse, the whole upper swash and head would have come in contact with the dog house.

The problem is, we don't have much to stand on trying to say that because of faulty build, my helicopter crashed. However, if we have several users experiencing the same thing, there could be some strength in numbers.
07-02-2008 07:26 PM
HOMEPAGE  
 
 
bigduke666
Heliman
Location: Stoneham Mass US

Funkey/Align 500 fuse

I too had this problem.
I have a 600e that I mounted in a Funkey 500E fuse, flew great for all of my test flights but always with a slight vib in the horizontal stab and in the weapon stores, any vib is going to be amplified at the extremedies. Slight blade tracking issue, no big prob right? Wrong, that vib unattended caused the bracket in the dog house to work loose from the epoxy the manufacturer installed it with. Battery change spin up the blades pull pitch and all hell broke loose. The bracket broke into 3 peices, this eliminated all stiffness in the dog house area allowing the fues from the mounting deck up to start vibrating side to side with the only thing to stop it as the swashplate. This really wasn't good as the bird was in fight and the swash impact and it's rotation only caused the vib to get worse.
The damage? Well Lucky for me I was only 5ft in the air, I shut it down and had it on the ground in a split sec. I too shook off the horizontal stab, shook a rocket tube right off and chewed up the glass around the opening of the swash. Not so bad and pretty easy to fix.
Now for the fix. Made a new bracket and glassed it in on both the front and the back sides also added glass to the inside face of the doghouse to stiffen it up but lastly I glassed in an X brace made of popcicle sticks up in the doghouse corners. Now it's as solid as Sears. And yes I now pay much closer attention to very close blade tracking.
07-04-2008 12:51 PM
 
 
Stet
Elite Veteran
Location: Long Beach CA

We made a really robust frame brace to connect to the doghouse. I think I will try loosening the blades and running a lower headspeed. If it still blows up I will throw my hands up and explain to my buddy that if he wants to buy everything sight, it will be up to him to get with the hobby program and make it work. Doesn't help that my buddy is my boss

keepin' it real
07-05-2008 06:19 PM
 
 
steph280
Key Veteran
Location: Irvine, California

Check out this thread. Helped with my vibration problem:

http://www.thetrexforums.com/?topic=1959.0
07-15-2008 09:09 PM
 
 
Sherman89
Heliman
Location: Morriston Fl

The dog house must be secure, do what ever it takes to make sure the dog house does not become a vibrator. Also, you may want to consider flying the heli before the body install eliminating a lot of the setup and potential vib problems.
07-17-2008 11:40 AM
 
 
1 page909 viewsPOST REPLY
HeliProz . ZoomsHobbies . HeliHobby

.
.
e-Align T-REX 250-450-500-600 > T-REX 600 600 / H500 Funkey scale builds blow up
 PRINT TOPIC Advertisers 

Subscribe to This Topic

Tuesday, December 2 - 4:06 am - Copyright © 2000 - 2008 runryder.com | email | link to rr | runryder needs cookie