250 blade 300X tends to tipover upon takeoff-- randomly

[Wolf714]

fairly new 300X is very well behaved. everything's worked pretty well with use of 255mm SAB blades, but recently I've noticed after spooling up to takeoff rpm, the heli wants to rollover on the right

can't figure it out anybody out there can u help me troublehoot?

I know to have the beast take over properly, the heli has to be about 2 ft off the ground, now I'm just worried when I see that roll coming, that I'm gonna shred the blades up obviously don't want that

 

[murankar]

Has anything changed mechanically? Swash level, sub trims good?

I would check for a level swash.

This is just a start. Others on here have more experience with fbl than I do.

 

[Lee]

Maybe vibes getting to your beastx. First replace the tape under the unit with 3M mounting tape, like the stuff they use for sticking go pro mounts. It can be bought in most hardware stores. Then make sure everything is balanced to reduce vibes. The beastx is bad when vibes are present, and the common issue from this is rolling right, but the new tape helps a lot.

 

[coolgabsi]

one video Spektrum / Horizon released right about when Beastx got popular.. was that when spooling up the beastx, dont sit on the ground too long with blades running at near hover or whatever rpm .. the bird will wanna tip over.. small or big.

not saying that, you are doing something wrong, it might just be that in those cases, you wanna not touch the Cyclic AT all. and go straight up on throttle without moving the cyclic stick.. cause 9 times out of 10.. and this is coming from HH... that , it will cause the beastx to over correct on ground and tip

Hope it helps

 

[Westy]

have you got this sorted? if so, I would like to know how you solved the problem

 

[Wolf714]

hey sorry 4 the delay. not solved yet. I actually sent the heli out 2 an Army buddy of mine who actually runs an aerial photography business, so he'll likely get a fix on it sooner or later.

rumor has it the beast, mounted the way it is on the 300X, is prone to problems. some say using different servo tape works. I'll post up when I get the full 411 ~

meanwhile if you're interested, you can see my vids on youtube:

render767

is my channel

cheers bro

Wolf

 

[coolgabsi]

nice to see you back here Wolf.. Was wondering where you went. Hope he gets it figured out. It is pretty crammed inside the heli.

 

[Lee]

rumor has it the beast, mounted the way it is on the 300X, is prone to problems. some say using different servo tape works. I'll post up when I get the full 411 ~

Thats exactly what i said further back in your thread. The reason i said it was cause it happened to me, and its a well known fact. Since replacing my tape, i've had no issue again.

"Maybe vibes getting to your beastx. First replace the tape under the unit with 3M mounting tape, like the stuff they use for sticking go pro mounts. It can be bought in most hardware stores. Then make sure everything is balanced to reduce vibes. The beastx is bad when vibes are present, and the common issue from this is rolling right, but the new tape helps a lot."

The tape should fix it.
Good luck

 

[xokia]

one video Spektrum / Horizon released right about when Beastx got popular.. was that when spooling up the beastx, dont sit on the ground too long with blades running at near hover or whatever rpm .. the bird will wanna tip over.. small or big.

not saying that, you are doing something wrong, it might just be that in those cases, you wanna not touch the Cyclic AT all. and go straight up on throttle without moving the cyclic stick.. cause 9 times out of 10.. and this is coming from HH... that , it will cause the beastx to over correct on ground and tip

Hope it helps

I'm just kinda wondering how you guys are trying to pop in the air? Are you just trying to give it throttle and lift off without cyclic input?

The beastx is kinda like what coolgabsi mentioned. I've had it on two helicopters now. If you just spool up and just sit there it will try to tip over. It usually happens when you get to about mid stick. Mine always rolled to the left. If you counter the roll it does just fine and then once your in the air it works perfectly.

 

[coolgabsi]

Like I said in that post. I always try to take off straight up without cyclic input. Beastx does its job as soon as skids leave the ground

Fly safe!! have fun!

 

[pvolcko]

So far I haven't seen this tipping effect on the 550 or the 300. Both use pretty thick double sided adhesive foam to mount the 7200bx. The 300 has a zip tie clamping it down too. Too much in my opinion. Actually compressing the foam tape at one end and making the 7200bx sit at a bit of an incline angle. Will probably cut that tie and redo it a bit looser if I see issues. So far though no oddities in control.

 

[Tony]

If you have a little bit of wind and are at mid stick with teh blades spinning, the wind can tip these things over.

 

[bmandery]

Curious is the new 3M tape corrected the problem? Looking are purchasing this heli really soon. But have a couple shop projects I need to finish first. I haven't posted on here in a long while and the blade 120sr got boring really fast once I was able to take it out side.

Thanks,
Brad

 

[Ryan Hebert]

I had this same problem, tried everything. I put the esc off of one of my 450's and the bird is flying at its best. My esc had gone out causing the heli to roll right on take off.

 

[Wolf714]

hey Brad wup

yea after I unstalled double side/ double thick 3M tape, & much laborious, tedious, irritating adjustments, tweaking, shredding a CF set of blades in the process-- I STILL have the problem!

It's either something very simple, random, or unknown to me -- or I guess maybe my AR7200 is defective. that'd be tough to realize-- because I know that unit is virtually bulletproof-- unless u crash full blast into cement ~

I'm tapped out dude-- can't understand.. what's 'modus heli- operandi' now is, when I spool up to takeoff rpm, the left servo ( left side of swash ) proportionally pushes the swash up, forcing the helicopter to tilt
right & this happens with NO INPUT from me on the right stick!!!

the Police made a great record back in the day called 'ghost in the machine' & I'll b damned I think that may just be my problem!!

it's driving me nuts man.. I've spent almost half the cost of the heli in spare parts/ repairs & my patience is nearly tapped out

cheers bro ~

Wolf

 

[pvolcko]

I just did a repair on my 300X and during test/tracking flight I found it was tipping right and a little back on take off. Had never seen this behavior before. It was enough to make me think it might blade scrape on take off the first time. I wasn't expecting it so I just took off like normal and when I saw it going over a bit I quick gunned the collective to get it up in the air and level it out. Found it was tending to tip that direction out of hover too. Pitch pumps were showing hard direction changes in both positive climb and negative dive. Piros were wobbling like crazy. Took a look at the swash. While it was level, at mid stick it was also significantly low as evidenced by the swash follower/driver arms. I redid the setup, centering the swash better this time, and it is now taking off without tipping at all. Pitch pump and piro behavior is cleaned up. This time when I setup the min and max collective pitch with the 7200bx the light was blue instead of purple.

I don't think the problem was actually the swash not being centered so much as the servo arms were not 90 degrees. They still aren't, but they are much closer.

So make sure your servo arms are close to 90, except the elevator arm which will appear to be a bit higher than 90 degrees since the servo itself is a little canted. Adjust swash links to get the swash up to a level that will make the follower arms on the bottom of the head close to 90 degrees at mid stick, and level. Use 7200bx swash leveling, setting G I think, to adjust servos to get it perfectly level even if it means they are no longer perfectly 90 degrees. Zip tie method works for leveling it.

Then put the head on and adjust blade link lengths to get the blades 0 degrees (or as close as you can). Then pick the closest to 0 blade and use it to setup cyclic pitch (the 6 degree deflection setting step) and collective pitch (min/max collective pitch angle, I use 12 degrees).

Mechanical swash and head setup are very important.

Over the course of many rebuilds, servo gear replacements, main blade grip replacements, and whatnot I was setting it up for 0 degree blades with the swash lower and lower, and the servo arms getting lower and lower which ended up causing me tipping issues on take off. This was due to travel asymmetry in swash as it traveled below 0 degree point for take off, due to the non-90'd positions of the servo arms in relation to each other at 0 degree blade pitch. There's only so much the 7200bx can do.

 

[Wolf714]

much appreciate the 411, however alot of it, due to my r/c heli repair competence, sounds like an alien language.. no offense -- I just am not prepared to properly go into the minutia of the AR7200 @ this time.

I do fly real AH-1Z Viper aircraft & others as well, w/ USMC- done it for over 20 years- so far as the mechanics of the swash & servo arms are concerned, I've got that prolly as perfect as can be.

what happened as a possible catalyst to all this recently, is that after the 300X actually flew into me, chopping into my arm a little bit (hey it was that, the ground, or my house -- I choose the least of the 3 evils-- once it landed in a mulch bed, the AR7200 initialized again. I'd never experienced that, so I thought that might be a notable event causing this current 'right tipover tendancy'. prior to that event, the 300X flew possiblt as well as any of those birds can. so SOMETHING electronic I believe, was jarred or damaged to make it behave now as if, upon takeoff rpm, the servo to behind & to the left of the swash moves up on its own- with NO right control input whatsoever. it's drastic -- I mean u can see the whole rotorhead move to the right, proportional to increasing throttle.

I tried resetting the beast X but I'm not sure if I did it right. I then rebound it, & still -- the 'ghost pilot' still wants to drag it over to the frickin right!

frustrating man, to say the least

when I do get qualified with the info you graciously posted-- I'll try it. for now? I'm grounded & looking for what possibly is just a simple electronic quirk; something that's easy to fix but invisible to a knucklehead like me

Wlf

 

[pvolcko]

Did you check the servo to make sure it didn't get the gears stripped or something in there jamming it up? I apply a little bit of down pressure and raise the arm with the tx collective, then pull up on the link a bit and move the arm down with the collective stick. The plastic gears in the servos tend to strip very easily. Always check them after every crash.

Also make sure the servo arm didn't strip out. I've never had that happen, since the gears seem to strip first, but that is also an issue that could cause this.

Lastly, you don't have any mixes setup in your Tx, do you? Maybe collective or throttle to aileron mix?

Otherwise, I'm not sure what would cause this. Don't see how the 7200BX could have been damaged in such a way as to result in that behavior.

 

[Wolf714]

hey yea the two 'crashes' I had surely would not render the very advanced & rendering technology of the beast X-- I'd say both incidents incl. the 'self inflicted' strike aforementioned to prevent probably much more damage were about as 'low impact' as they come..

I did manage to factory reset the AR7200- finally- & now as a very capable pilot & a friend out here for my part anyway 'coolgabsi' suggests that I may have a vide problem, or it's a servo or servos.. the servo on the left behind the swash moves on it's own when I spool up to takeoff rpm -- no input whatsoever. & I know all about taking off quickly; not loitering or giving inputs to the beast b4 takeoffs.. I have a 450X which is setup perfectly so that's my 'control' reference here -- & 4 the life of me -- I can't figure it out! I do understand the sensitivity of the mechanical setup; I've gone from using a swash leveler to the point it's 5 by 5 far as that goes, only to then have to adjust the swash links to physically make it fly right. & it did once fly very well! that's the major frustration -- all I did was change out a main shaft, a spindle, & installed CNC swash & grips -- now I have a bird that's flying according to a ghost I can't troubleshoot dammit!!

I'm gonna post a video of it's behavior soon on my youtube: render767

that's my channel I've got like 20 vids mostly of my 450X but also one of the 300X when she was flying right ~

I haven't given up -- this will be solved

that's actually one of the things I love about the rc craft -- the challenge of it.. very cerebral; even when u think u have all the bases covered -- here comes something out of thin air which we didn't expect..
I like that aspect actually

cheers bro ~

Wlf

 

[iceyo]

not sure if this is relevant in anyway, but I have a trex 250 with a 3gx mrs and if i touch the heli at all when i connect the battery and the 3gx is inizializing, it will tip over at spoolup.. mine does always tip to the right tough.. quick fix for me is to unplug the battery and reconnect it...