Owners Club: thoughts, issues and fixes - OOTB ERRATA

[ducatimoto]

I've got an old trex250 in very good mint and i bought a DFC a few days ago in order to sell it
This morning i set up ar7200bx from my crashed 300x
I've done a video of the first test flight uploading for the moment
I will post it if you want to compare with 300x's first flight
My first impressions are that 300x is more precise but perhaps need to play with pods on ar7200bx
Edit: i Will do another post for sharing comparaison's impressions on these two birds.

[jamesb72]

Originally Posted by ducatimoto

i bought a DFC a few days ago in order to sell it
This morning i set up ar7200bx from my crashed 300x .....
My first impressions are that 300x is more precise but perhaps need to play with pods on ar7200bx

Thanks, will look for other thread, there are a few param changes between 300X and my 250, and pots are quite different, so a lot of this may be tuning to your preference (servo geometry on the 250 is not ideal for FBL, the DFC swash should fix this though!)

My 250SE super combo with align FBL head (non-DFC) has dial1 8:00, dial2 9:00, dial3 8:45, and I tweaked params following the excellent beastx v3 tuning guide on helifreak.

[R3L72]

Originally Posted by ducatimoto

I've got an old trex250 in very good mint and i bought a DFC a few days ago in order to sell it
This morning i set up ar7200bx from my crashed 300x
I've done a video of the first test flight uploading for the moment
I will post it if you want to compare with 300x's first flight
My first impressions are that 300x is more precise but perhaps need to play with pods on ar7200bx
Edit: i Will do another post for sharing comparaison's impressions on these two birds.

I still have my 250 FBL with BeastX and I've planned to keep it along side the 300 X; so if I can get my Trex 250 tuned as well as the 300 X, I'll be a happy camper. I also got the DFC assembly for it but was waiting until the Swash Plate that comes with the new 250 Pro DFC kit becomes available; the DFC kit I bought just states to use the standard 250 swash when installing.

I'll be looking out for your new post!

[honkytown]

back2topic, pls. (250DFC is my next favorite)

Originally Posted by ducatimoto

bought a new one yesterday
can't wait for my spares
and a good friend will buy it when rebuilt will be done
with this new one i've had heavy vibrations like you honkytown
did stevebaker's mod and check linkage
there was a lot of tracking
after that, hover was vibration free, even in IU2 (100%flat)
so it's supposed to be hard 3D capable out of the box, it was real for my first one, not exactly the same for the 2nd one
but we must check everything before flying, old flyers told me that...a long time ago and forgot a little bit with eflite products

i am a sort of glad that i am not the only one, on the other hand i feel sorry for you got a lemon this time. your are the first who crashed, inverted; the second who crashed was inverted too, just a coincidence?

i am little worried about that there are so few user reports about the 300x so far, if i look at the 130x i feel the ratio is something like 15:1 for the 130x, youtube shows the same. Guessing 130x is i bigger market and 300x is a niche, additionally there are many customers who don't use their purchase just put it in the shelf instead of using it for 3d flying...anyway i feel they sold only a handful of 300x.

here comes the picture proof of yesterdays test flying, the before pictures are the servolink out-of-the-box(ootb) after 25 flights, the after pictures are the last three flights, after i flipped the servolink up side down, modified the gear mesh(more clearance between servolink and motor bell), tighten up all screws etc.
i assure you again, there was a minimum of 1mm clearance between servolink and the motor bell after i pushed the head very hard towards the front.

now i am looking at this pictures and thinking, the servolink could have broke during flight

[InFocus]

I suspect the 130x will have more units sold overall because of its lower price, and ability to fly it in smaller areas.
However, something to remember right now is the 130x is available in the USA, and the 300X is not. This would also skew the number of posts about each heli.

Ducatimoto: did your servo link also get worn down by the motor?

Also, what are other peoples thoughts on this 'issue'. I can not determine based on the posts here of what is the root cause of the issue. I've seen 3 things reported:
a. sometimes there is an unexplained vibration
b. There is flex in the frame if you force it with your hand
c. something move/flexed enough for the servo arm to touch the motor can.

Some thoughts or things to ponder..

What is the cause for the vibration? If something is out of balance then I could see where an excessive vibration could generate enough forces to bend/flex the frame as shown seen in b.

Could a small vibration turn into a big vibration if the frame is not stiff enough to contain it? Would that explain why when someone stiffened that part of the frame, the vibration 'went away'. Did it really go away, or is it just now better contained?

Is it a 'vibration' i.e. caused by spinning part out of balance, or an FBL induced shutter, like when you have a gain setting set way too high?

[ducatimoto]

My understandings:
There are things to check especially length of linkages
As the frame can flex, if there's tracking it could increase dangerously with special HS
I think that stevebaker's mod and carbon blades could make me wait for frame upgrades
inFocus: no problems with servo horn and motor

[honkytown]

yes the release of 130x&300x was splitted, it was a surprise for the EU the early rushed release of the 300x and the US was surprised about the 130x was pushed out. both birds appeared suddenly on the market, both were several times delayed for weeks and month, both were announced for later this month(juli, latest official news from HH employees on HF).

if you have followed up the news and misc boards since the first advertising of 300x/130x and the delayed release dates, it is hardly to belief it wasn't a rushed release of both birds to calm the customers down(250dfc release anyone?) they stated they have enough units(130x) they should last for weeks, so why no release of the 130x in EU?

if i compare the responses in the 130x section compared to 300x, yeah this ratio is really overwhelming.if i scan misc boards in EU in different languages, i can't find hardly any user reviews or something like this. helifreak seems always to be the source for leading information. another sidenote in this thinking puzzle, many month ago they published silently on their website the manuals fr/ita/de/en as pdf, after reading them i found some mistakes in all except the EN-version, so i posted my findings on HF and someone from HH thanked me for spotting this. but all mistakes made it still to the printed released manual...that's odd.

some thoughts of mine, it's raining today so no testflights for me. my wish remains, i need a highspeed cam to track it down inflight

@ducatimoto
can you compare your gear mesh on both birds, pls? is the clearance between the servolink and motor bell on the closest position on both birds the same?
thx .)

[ducatimoto]

Originally Posted by honkytown

@ducatimoto
can you compare your gear mesh on both birds, pls? is the clearance between the servolink and motor bell on the closest position on both birds the same?
thx .)

sorry, but not possible because on the crashed one main shaft is broken in the gear and the clearance between servolink and motor means nothing because of broken frame

[honkytown]

null problemo ducatimoto, should have thought about that.

maybe i have nailed it down for me, still don't get how this could be a single failure only on my little bird. however i am happy if this will work out for me, but i am awaiting a response from HH, so until then i don't want to tinker anymore or fly cause of the weakened servolink.

for my next flights, thinking i will paint the top of the motor bell with a white marker and fly only one move after another and check the painting on the motor bell between different moves. starting with flat TC70% and going slowly up until hitting 75%

in my last videos you could see the head movement and the back servo cage movement, until today i overlooked it somehow. there are uneven gaps between both rear servos and the cage where they are mounted, watch the pictures below the gaps are easy to spot. the cage shouldn't move like that, it's design part of the head stiffness, imo. i did again some videos, making more videos than flying lately

remember, the heli isn't nailed down or glued to the table, so it ain't easy to hold it calm for the cam and pressing the head without moving the heli, i am not hulks son either
on the end of the first video i am pressing very hard and the clearance should be big enough, still the link was grinded again on the last three flights!

compare the head with filled gaps and without
[ame]http://www.youtube.com/watch?v=H4PBPwkWwSk[/ame]

added 3x 0.5mm lexan
[ame]http://www.youtube.com/watch?v=QOCnA9zBRjM[/ame]

it looks promising to me. tapping both servos with double tape together, surrounding them with a big tape and try again, could be enough. if not there is plenty of room to stiff this whole part up, if you look closely on the pictures. between the servo cage and the head is enough room to CA some 2mm carbon rods in or with some two component adhesive filling up. left and right from the servo mounting are holes too, could be filled with something to make it even stiffer. the part between the head and the ar-bracket looks very weak too.

thoughts, compares?

[stevebaker]

I have a little nick in my servo link. I have no idea how it got there as I don't have any flex in my head with the stiffener - maybe it was always there?
Will have to keep an eye on mine - maybe like you say paint the motor rim.

[honkytown]

swap the servo link up side down and inspect it closely before installing, picture proof it, then we will know it soon

[stevebaker]

Great idea.
I'm waiting for my DX8 to get repaired and returned to me now. Hopefiully I'll get it back for the weekend when I get back home from a business trip.

[R3L72]

Originally Posted by stevebaker

I have a little nick in my servo link. I have no idea how it got there as I don't have any flex in my head with the stiffener - maybe it was always there?
Will have to keep an eye on mine - maybe like you say paint the motor rim.

I'll have to follow this Thread closely...no problems on mine yet but I haven't done any 3D yet either.

[ducatimoto]

@honkytown:
I've done your lexan mod. Seems to improve the stiffness "on the bench"
Will test fly later and report here

[honkytown]

Originally Posted by ducatimoto

@honkytown:
I've done your lexan mod. Seems to improve the stiffness "on the bench"
Will test fly later and report here

nice hopping the results are what i'am expecting

have fun!

[honkytown]

got an two answers from HH?!

first one: i should send the unit in, they suspect false handling and/or user error...

second one: they have no spares yet, but are willing me to send a new servo link when they are in stock...

anyone need spare parts for his kick ass 3d adrenaline machine?

[InFocus]

Originally Posted by honkytown

null problemo ducatimoto, should have thought about that.

maybe i have nailed it down for me, still don't get how this could be a single failure only on my little bird. however i am happy if this will work out for me, but i am awaiting a response from HH, so until then i don't want to tinker anymore or fly cause of the weakened servolink.

for my next flights, thinking i will paint the top of the motor bell with a white marker and fly only one move after another and check the painting on the motor bell between different moves. starting with flat TC70% and going slowly up until hitting 75%

in my last videos you could see the head movement and the back servo cage movement, until today i overlooked it somehow. there are uneven gaps between both rear servos and the cage where they are mounted, watch the pictures below the gaps are easy to spot. the cage shouldn't move like that, it's design part of the head stiffness, imo. i did again some videos, making more videos than flying lately

remember, the heli isn't nailed down or glued to the table, so it ain't easy to hold it calm for the cam and pressing the head without moving the heli, i am not hulks son either
on the end of the first video i am pressing very hard and the clearance should be big enough, still the link was grinded again on the last three flights!

compare the head with filled gaps and without
http://www.youtube.com/watch?v=H4PBPwkWwSk

added 3x 0.5mm lexan
http://www.youtube.com/watch?v=QOCnA9zBRjM

it looks promising to me. tapping both servos with double tape together, surrounding them with a big tape and try again, could be enough. if not there is plenty of room to stiff this whole part up, if you look closely on the pictures. between the servo cage and the head is enough room to CA some 2mm carbon rods in or with some two component adhesive filling up. left and right from the servo mounting are holes too, could be filled with something to make it even stiffer. the part between the head and the ar-bracket looks very weak too.

thoughts, compares?

Looking at the top video. I do not think the amount of flex in the head is extreme. The Blade 450 3D has about that much.
This is my opinion.

Have you found the root cause for the vibration yet? I really think that is the bigger problem to solve. If you did not have the vibration, then I doubt that the servo link would have had contact with the motor.. Have you checked for a bent feathering shaft or main shaft? There are some other posts here also about some vibrations as well as it relates to the blade balancing.

[FailureToFly]

Originally Posted by InFocus

Looking at the top video. I do not think the amount of flex in the head is extreme. The Blade 450 3D has about that much.
This is my opinion.

Have you found the root cause for the vibration yet? I really think that is the bigger problem to solve. If you did not have the vibration, then I doubt that the servo link would have had contact with the motor.. Have you checked for a bent feathering shaft or main shaft? There are some other posts here also about some vibrations as well as it relates to the blade balancing.

I think InFocus is on the right track here.

The frame seems pretty stiff and the flex seems reasonable for a plastic framed heli...likely very similar to the 450 3D and 450X.

If you have noticeable vibration (espec on spool up) and you add in throttle too quickly, you are going to get major head movement like you are pretty violently pushing and pulling the head around but extremely quickly. It might be at these times that the flex becomes dangerous and causes the link to touch the motor can.

Just an idea anyway.

[honkytown]

again, thank you for your thoughts!

yes i have read the postings about the blade balance, checked blade balance several times and it was nearly perfect, the blade with the red tape is slightly heavier, CoG was nearly the same ~<1mm difference, however i put a 0.5x1.0cm tape on the other blade and it was even balanced but haven't a testflight with this. i can remember i have switched the blades after i couldn't fly at TC75% anymore, but the vibes got only stronger so i swichted them back. always marking my blades+bladegrips, even on my mcpx^^

i was thinking the same this morning, the servo cage can't be the root cause of this, maybe only a way around. have only visual looked at the main shaft, head+collar wasn't removed yet, was awaiting a response from HH. how would you explain the developing vibes after some flights and then i was forced to go <75% TC. after tighten up all screws and loose the gear mesh i could fly again at TC 75%? this makes no sense to me.

somehow it's tempting to find out the root cause of the vibes, on the other hand i send it in and have to play the waiting game until HH resolve this issue or just blame it on me. haven't decided what to do now, part this bird out and use the ar7200bx on other or just another try & error attempt...

[ducatimoto]

here it is
don't know if it can be seen on video, but i feel it's a great improvement
more precise and more agile
[ame]http://www.youtube.com/watch?v=a1Hbc0zakTY&feature=youtube_gdata_player[/ame]