450 T-Rex 450 Pro DFC.... Not until the fat lady sinks....

[Doum066]

Greetings guys....


Well... i was afraid of this moment.... but there it, my first retarded-stupid-beginner's crash.... I tried my idle settings before able to do approriate circuit on reg curves... i went as everyone said.. the faster it goes, the more steady it is... it was.... until i lost control and tried to coupled with a tree... :S I feel sooo bad, and stupid.. :S so here i am.... asking advice...

How to know what needs to be changed... i mean, others from obvious parts... i mean, how to know if i need to change motor, servos, ESC, Receiver/Gyro (AR7200X)..... Here's some pictures of my dumbness action :S






Thanks

Doum

 

[Lee]

Sorry dude, but its part of the hobby. Just build and fly again.
First have a read of my Check list after a crash
See if that helps.

 

[breeze400]

Other than the obvious electronics should be fine. Check servos see if there striped or not. The rest you have to take apart. Check main and feathering shaft by rolling them on a piece of glass. See if there bent. Or not. That's the extent of it. Till you get her apart you won't know what you need!

 

[Doum066]

Great, will be looking to that check list. )

I've already started to add stuff to myc art on my online stuff, all the obvious broken part so far I had a lot of them already, but need to refresh my spare parts lol.

The only things that concern me is if any electronic parts are damage....

as Tony'S signature says « Every Flight Is A Test. Every Crash Is A Lesson! -Night Flyyer »

Here goes my first lesson.

 

[Tony]

It's the truth. Every time you put the heli in the air, you are testing your skills. When you crash, (yes when, NOT IF), you just need to figure out what happened and learn from it. Chin up bro!

 

[Doum066]

Well, the order has been shipped, so i might get my part by friday, and rebuild that thing.... lesson learned, not playing with my idle curves which might had been wrong set for my level.... i shall try to fly with my normal settings I've learned that this bird, can fly away from you by way fast. One thing i've learned, real curves and Phoenix 4 sim curves aren't acting the same way even though you end up with same pitch, throttle and so on..... The speed and turn of things caught me off guard,, so much that i didn't even though of switching back to norm curves and put it on hover then try to get it back... i did the same as someone loosing control with his car on ice, and even though he knows, not to apply full brakes, the first reaction he has is, applying fill brakes.

I gotta find perfect curves to learn, i think the problem was, i got used to my normal curves which has variation on throttle and not much on pitch, so getting low stick got throttle down a bit, so when unsure it savec me.. but with my idle up curves with a steady straight line (0-60-80-80-80) or so... well there is no throttle down to hel same my lost control, only pitch was affected.... and i happened to fast, i wasn't able to gauge the negative/positiv pitch variation and control....

Now more than ever, RC Heli pilot amaze me


Cheers

 

[stokke]

It's recommended to get comfortable in Normal mode before trying out IU mode. The good thing about Normal mode is that you can throttle down to get control back - and also land without killing the helicopter.

Good luck with the repairs!

 

[Doum066]

Well.... i'm finaly done with the repairs.... lots and lots of broken parts, as for electronics, only ended up with a broken rudder servo, tried to fix it... but a little complicated for a start... so new rudder servo, so far i only tried it indoor no blades on, motor seems perfect, all other servos reacts properly... servers mechanicly centered more than ever.... that was a nasty crash, but gave me exerience on not what to do and did so much damage, i completly stripped down the bird and redone it.... so basicly this is my second heli build

Here's some picture of the stage...


As you can see on this one, even the bottom bearing shield of the swashplate broke loose.....


Bye, bye nice canopy


Lots of broken stuff from the front torque tube assembly, gears down to the tail rotor blade holder set...


Both bearing of the main shaft block came loose of their place, the bottom one even stuck on the main shaft, which let me no choice to strip down the body since i couldn't pull up the haft, not down to take off the main shaft.... taking that bearing was tricky....

The motor pinion felt down the motor shaft... also was a pain to take out to replace it....



Once most all of it was triped down... and alost ready to start the rebuild...

And now, what it finaly looks like




Had to modify the canopy also as my other one so it doesn't get too close of the main gear... it gave me a reason to get myself a Dremel.
On the rebuild i'Ve also noticed the battery mount is also broken, the slots where tou slide hte bottom of the canopy into....

Now i can't wait to try it out... and this time, no more idle curves for me for a lonnng time, until i can fly normal stuff and circuits.

Take care guys.

 

[canongraphy]

wow you really stripped that baby down! hopefully you used Loctite where needed
looks really good, you no longer have a wrecked bird, its new again!

 

[Tony]

Crashes suck, but are a necessary learning tool unfortunately. Can't wait to see it in the air once again!

 

[Doum066]

Well, if the weather stays nice as it is now, i might try it out later tonight.... but i'm wondering if i did fix the main rotor head properly.. as far as i can remember when i first assembled the bird when i got it... the rotor holder when not held, were droping by themselves as the rotor grip arms does.. but now, when i screw all the way down the color skrews in the feathering shafts through the rotor housing, it stays as is.. ie: if i let the holders level to each others as if with 0 pitch, it stays like this, but move smotthly... so is the way i made it before wrong or now... that is my main concern.

I mean the head itself, not attached to the blades, nor the mains shaft, simply the rotor head assembly in my hands... I'm having a hard time to find my words to explain, not always easy to explain yourself in a second language. I might make a little quick moving latet on tonight... Until then, here's a little snapshop i tried to explain with.



Thanks

 

[coolgabsi]

ok so how hard is it to move "A" the blade grips ? is it binding nominally at some points but when you move it it moves like with a gear inside (like moves in steps .. ) .. You are right.. Ideally the blade grips are supposed to be smooth and fall on their on weight

What has happened is that the bearings are wearing out. If it takes more than a touch of a finger I would say to move the blade grip, from one position to the other. Then I would suggest changing . cleaning of main blade grip bearings (radial ones) and also lubing the thrust bearings (3 peice ones) ..

And yes this happens after crashes.. dust.. and all that gets in.. Or just normal wear. I flew mine for a while with alittle choppy blade grip .. but all in all its more work for servos.. and too much bind can cause a head bobble or something like that.. or even a vibration..

Till I can touch it I cant tell you if its good or not. .so clean everything.. and see where you are at..

 

[Doum066]

Thanks for the reply Cool,

Actualy i already changed mostly everything, feathering shaft, thrust bearing on both grips, inside bearing on both grips, the only thing i haven't changed is the ouside vearing on both grips, the plasit dampers, the collar and the copper washer, i jsut redid everything, thinking i might haven't pushed far enough the inside bearing on any of the two grips.. but still does it, indeed, when i turn the grips, it feels like a stepping going form a position to another, i was looking how to describe it and you did it.

I'll try to take out the outsides bearing and change those two also.

 

[Doum066]

BINNNGOOOO

That was it.. changed the outter bearings on both grinps... and no more stepping when i turn the grips now, one of them falls under it's own weight, the other one is a bight tigher though, but i presume it's normal, even Tony if i remember had this little thing when i watched is 450 Pro build movies, i presume it's the side that we screw in the shaft first and use to slide the shaft through the grips and housing.

God damn... until i fnish this up and settle the problem, darkness has come... gotta wait tomorrow to try it out... we had not much wind today and tomorow is supposed to me a nicer day.... but i guess you all know what i mean when i say, tomorrow will be hell of a long day at work, waiting 5 pm to pop lol

The good thing about thise crash and problem encoutered is, each rebuild, makes it bettter than the time before, since you gained experience fixing it and setting it up

 

[Doum066]

Well, tonight was the night. I took her out for a try... i just had the bad idea to land on the grass, so the tail rotor touched the ground, after 2 times i get it now... no more Had to change the torque tube front drive gear, then later i took her out for a try.... this time, in a parking lot. So far so good, i flew 3 packs, then it got too cold outside and called it a day/night. Now is time to check it out with a good coffee to see how part are stil tight etc...

I forgot to start my timer on my second pack and flew too much, i know the 20 % law for lipos, but i'Ve also read that you can't charge a liPo that got down to 3.0v... can i still use mine even though my sentry says it's down to 4 %, but it still has 10,45v (average 3,48v per cells).... or should i retire it?

 

[Tony]

YOu should be fine on that battery. Just try to charge it and see what happens. And congrats on bringing it hope in one piece. Now you know what we are talking about with stripping gears when it hits so much as a tick turd hahahahaha.

 

[Lee]

The battery will be fine. Just charge it at a low ampage, say 0.5A to bring it back up slowly. Well done on the flights.

 

[Westy]

Awesome! good read! ... sad and happy for you ... but the heli looks nice ! Great Job! Have you tried those Super hard gears for torque tube stuff?

 

[Doum066]

The battery will be fine. Just charge it at a low ampage, say 0.5A to bring it back up slowly. Well done on the flights.

Thanks, i exactly did that, Storage charged it and no problem. What should i do with the pack i crashed with? Sounds stupid, but LiPos kinda scare me.

 

[Doum066]

Awesome! good read! ... sad and happy for you ... but the heli looks nice ! Great Job! Have you tried those Super hard gears for torque tube stuff?

Nope, so far i only bouught the normal stuff... That darn 450 Pro DFC is a damn demon for a beginner.... i'm starting to belive i took a hard one to start with....