Broke rear ELE mount again....

[jwatts007]

This was my set up that I was using when the mounts broke
Swash angle 270-135-45-0
Distance.....70-99-99-0
Cyclic ring...80
pitch pump..30
digital correction on
pitch 93
cyclic 103
710 blades

style 91
agility 94
gain 90


I now Have 100-100-100 in the distance boxes 70 cyclic ring 75 style....

Thanks for your help....

[Phil777]

I'll compare it to mine tomorrow, I'm wondering if it's possible the screws or bolts I saw in the pictures are being over tightened and weakening the elevator mount,

but if your confident that's not the case I'd contact your local distributor to see if anyone else has reported the same issue. it could of been a bad batch that slipped threw qc.



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[jwatts007]

Originally Posted by Phil777

I'll compare it to mine tomorrow, I'm wondering if it's possible the screws or bolts I saw in the pictures are being over tightened and weakening the elevator mount,

but if your confident that's not the case I'd contact your local distributor to see if anyone else has reported the same issue. it could of been a bad batch that slipped threw qc.



Sent from my GT-I9300T using Tapatalk 2

They break whether screws or bolts are used...there are few others that have had them break...others have had 100s of flights of hard 3D without any breaking...maybe the servo interactions are happening too fast and not long enough too strain and snap the mount...I fly rather slow...maybe when i am pulling a big loop the strain is sustained long enough too break them....a lot of maybe this or maybe that I know...the distance settings in the V Bar are correct if you do the maths.(dont no why it has 99 and not a 100 in the 2 boxes) but that must already have been solved in the helis design...therefore we should be setting the distances at a 100...by doing this the throw of the ELE servo became greater I had too reduce the cyclic ring as it was binding...so there must have been interactions with the other 2 servos set at 99...

[jwatts007]

This is how too measure a 135deg swash...the G4s swash is the same as this...if this method of measuring it is used the setting in the distance boxes must be equal ie set at a 100...by setting the ELE too 70 surely things must go out of order...and cannot be correct....

[Phil777]

I wont pretend i know how to measure a swash correctly but there was some pretty knowledgeable guys on here who worked it out to get those numbers, which have been working great for so many.

But if you found some numbers that work better for you, use them for sure, but it still doesn't explain why your bracket was breaking

While rebuilding my e720 this weekend, i realised on the elevator servo you have to trim the servo space tab or else it will hit the elevator arm bracket, (only remembered because i send the servo for a service)

Is it possible you didn't trim this tab and during flight your elevator arm could be constantly hitting this causing vibes that crack the mount? or hitting it quick enouh it weakings it?

I notice the other guy with the issue in his pics had not trimmed this tab.
Just a idea, what do you think?

Did you contact your local dealer to find out if your the only one or if there is others?

id like you to send me your file or attach it to this forum so i can have a look at everything, if you don't mind.

[jwatts007]

Originally Posted by Phil777

I wont pretend i know how to measure a swash correctly but there was some pretty knowledgeable guys on here who worked it out to get those numbers, which have been working great for so many.

But if you found some numbers that work better for you, use them for sure, but it still doesn't explain why your bracket was breaking

While rebuilding my e720 this weekend, i realised on the elevator servo you have to trim the servo space tab or else it will hit the elevator arm bracket, (only remembered because i send the servo for a service)

Is it possible you didn't trim this tab and during flight your elevator arm could be constantly hitting this causing vibes that crack the mount? or hitting it quick enouh it weakings it?

I notice the other guy with the issue in his pics had not trimmed this tab.
Just a idea, what do you think?

Did you contact your local dealer to find out if your the only one or if there is others?

id like you to send me your file or attach it to this forum so i can have a look at everything, if you don't mind.

Hi Phil...yes I did notice the tab catching the ele arm when I built the model and fixed that...the heli did fly nice with the settings I got of here for the V Bar...at least I never noticed anything wrong when flying it...it also flies very well now with the settings changed in fact to be honest with you it may be even better now and there is know interaction with pitch and cyclics...I have only had 6 flights with it with these settings it may break again yet...I do know the maths used too get the 70-99-99 settings they are rather simple too arrive at...but I think they are incorrect and I stand by that...if you measure it as in the diagram (as a 135 swash is measured too centre of main shaft) you must end up with equal distances by reducing the distance too 70 on the ELE you must be causing the servos too bind against each other...I have by PM spoken too several TT pilots...one guy says vibes may be causing the mounts too break...although I have never suspected that myself as the heli is so smooth and shows know signs of any vibes at all...my G4 also has been flown by a very good pilot doing hard 3D and the mounts have not broken...I fly more FC3 smooth big air stuff and break the mounts within 20 flights if I am lucky...I will put my settings up on here for you later to look at...my main concern with this model now is safety the last time it went down in the middle of the field moments later it could have been in the landing area out of control...

[benko]

Same problems here, G4 Nitro, Flybar head, strong Futaba Servos (37kg).

First time, two weeks ago, after maybe 30 flights with the G4, I lost control of elevator in flight and crashed. Both holders were completely broken.

Second time, last week, only three flights after I had replaced the mounts with new ones, it happened again, fortunately I took a look after each flight and noticed it on the ground.

This time I put washers in, hopefully that will fix the problem. Unfortunately there were no servo screws in my kit, so I used what I found at home.

[navyraptor]

you may have those bolt too tight

[jwatts007]

Originally Posted by benko

Same problems here, G4 Nitro, Flybar head, strong Futaba Servos (37kg).

First time, two weeks ago, after maybe 30 flights with the G4, I lost control of elevator in flight and crashed. Both holders were completely broken.

Second time, last week, only three flights after I had replaced the mounts with new ones, it happened again, fortunately I took a look after each flight and noticed it on the ground.

This time I put washers in, hopefully that will fix the problem. Unfortunately there were no servo screws in my kit, so I used what I found at home.

Attachment 460305 Attachment 460306 Attachment 460307

What engine are you using...mine has the YS 120 in it...I do not fly mine much at all now and when I do I am always thinking about the mounts breaking again...

[Rob43]

Originally Posted by benko

Same problems here, G4 Nitro, Flybar head, strong Futaba Servos (37kg).

First time, two weeks ago, after maybe 30 flights with the G4, I lost control of elevator in flight and crashed. Both holders were completely broken.

Second time, last week, only three flights after I had replaced the mounts with new ones, it happened again, fortunately I took a look after each flight and noticed it on the ground.

This time I put washers in, hopefully that will fix the problem. Unfortunately there were no servo screws in my kit, so I used what I found at home.

Attachment 460305 Attachment 460306 Attachment 460307

Actually, it appears to me on this arrangement should have the cap screws reversed and the grommet thimbles arranged with their flanges against the mount.

[djedje]

hello, sorry for my English, I use google translation ....
the problem that we encounter on our raptor is an stress ( front / rear) of support aluminium.
With the vibrations of the nitro, it causes breakage of aluminum support.
After analyzing the break, we see very clearly that it is an effort front / rear and not side.
here the solution in pictures . I have over 50 flights and no breakages.

Jérôme

[PlaneHazza]

I'm about to buy a used G4 and this thread is making me a little nervous

Has a stronger part been released to fix this issue?

[Phil777]

I wouldn't be concerned there is only a select few that have this unfortunate issue,

I have 2 G4s one has been crashed so many times I can't even remember how many and I have never broken this elevator mount. My other one used for F3C has been flawless as well,

There might of been a bad batch or just the incorrect screws or over tightening with a combination of tunning issues causing it to fail.

It is a fantastic machine, smooth and precise, and has a unique feel that no other machine on the market can match.

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[sjsamuel]

Originally Posted by PlaneHazza

I'm about to buy a used G4 and this thread is making me a little nervous

Has a stronger part been released to fix this issue?

Like mentioned earlier I think this was a select unfortunate few that had this problem. I had one break as well. So I replaced it and bought an extra just in case
However, I've got tons of flights since then with no problem. This is the most amazing nitro setup out there..you will not be disappointed.

[FLAU]

Don't forget TT is the first company that delivery alu servo arm in there kit.

Olso there is no give in this push-pull system so set it up as in the manual.
If you thighten the servo first before you put on the servo arm there will be stress, and yes if you
squeeze the snot out off the rubber servo grommets there is no way these rubbers can upsorbe fibrations from the engine.

Frans.

[jwatts007]

I really dont think the cause of the failures are in anyway related too how the servo is fitted...I have seen myself a G4 flown for many many flights by 2 owners fitted with a OS105...the engine was then swapped out for a YS 120 and within 20 flights one the mounts broke...this was the best indication to me that it is vibe related...my problem started when I swapped out a OS 90 HZ for a YS 120...I see benko has had the same problem using a FB head so that would rule out the set ups with the FBL gyros...all it needs is another 2-3 mm thicker mounts and then I am sure this would not happen...