Trex 450 drifting problem?

[Mike_117]

I just got finished building a Trex450s with a DX6 tx and a 500T gyro.. I go for my maiden flight and I can't get the drifting problem to go away.. If I play with the trim on the TX, it acts like it will tip over.. If I level it back it wants to slide left.. There must be a simple answer yet I thought I have tried eveything on the radio to try and make it not drift.

[Mike_117]

Nevermind...
it drifted straight into the ground.. costly newb mistake.. It will be sometime before I get close to airborne again.. I will probably invest in a sim. hehe..

- It was a very costly one... somehow. I broke:
1. blades
2. main spindle is bent
3. flybar is bent
4. flybar control set split in two
5. tail case set
6. tail rotor holder
7. main gear
8. stabilizer fins
9. SF mixing arms
10..........still looking..

Lesson to newbs.. wait for a nice day outside.. tried to hover in my livingroom. .(it is a big area granted.., but not big enough.. ) it was snowing outside.. so no go ...I was the only one in the area.. I was doing pretty good then all of a sudden it shot forward and I couldn't pull it back in time.. and whammo, nicked (some metal POS candle stand that I should have moved....doh!) and pieces started flying..

way more costly than a $1 cx blade........

[Mike_117]

Sounds bad... looks bad.. $$$$

- Total loss $115 .

[Mike_117]

After reading this post again ...I could see that some are like..... "He hovered in his living room!"..

After I pushed my furniture to the side... I still had a good 12"x15" area to hover on hardwood.
Although it appears to be enough room for an experienced rc heli pilot to hover... I am not an experienced rc heli pilot, (as if you can't tell) and I will not take that chance again.. the trex is too big.., luckily I was on the other side of the room when it crashed..

[PilotDane]

I do most of my flying inside so that is nothing unusual in my book. I find hovering outside on a windless day is easier than hovering inside the house. The TRex moves so much air that in the house it creates it's own wind, so shortly after takeoff you are faced with confused downdrafts and crosswinds that will keep you on your toes. (The picture is of me hovering in the game room. The flash stopped the blades, but it is actually hovering.)

You mention the heli always had a drift. Were you trying to lift off or were you in a stable hover when you notice the drift?

When standing behind your heli (tail-in) the TRex will somewhat strongly want to lean/drift to the left just before and during liftoff. You have to learn to add right stick (aileron) to counteract it. A second before liftoff I give about 1/3 to 1/2 right stick then as the heli lifts off I bring the stick back to center so that by the time it's fully in the air the stick is back at center. It's just something you have to learn and do by feel.

If your TRex is drifting while in a hover you need to adjust your control linkages (I don't like to use trim in the radio. I try to get the heli mechanically correct). When standing behind the heli (tail-in) the heli will move in the direction the swash plate is tipping. If the left side of the swash is low, the heli will go left. To start out you want your swash dead level when your control sticks and servos are centered. The control arms on your servos should also be level/horizontal. If after getting everything adjusted and your heli still wants to drift in a hover than you can adjust the linkages to compensate. If it drifts left, adjust the linkages to either raise the left side of the swash or lower the right side. Once you get it as close as possible mechanically then it's O.K. to use a notch or two of trim on the radio. With the linkages adjusted on my SA it hovers beautifully with no trim in the radio.

[Mike_117]

PilotDane -- Where's the helicopter? just kidding. That carpet is something. Nice gameroom.. I painted mine a dark maroon for cinema feel. I don't have any pinball (wife says they are too expensive) but I do have a nice setup, pool table, dart board, card table, SXRD 60" w /bose surround.... I could fly down there but I'm afraid of hitting the TV with flying parts!!

- The drift problem was fixed..( another newb mistake - tail blades installed in reverse..:))
once i fixed that I could lift without the constant drift...
Your right, there was slight left drift at liftoff later but I was mostly fighting the sticks to keep level.. It was controlled until the heli took off foward. I let it float too long before I made the correction trying to ease it back. .... knicked the metal stand... and kaboom!! didn't take much. ...

[Mike_117]

I realize now, most of my carnage is from flying with the carbon blades that came with the kit.
If I started with woodies, the damage would have been less severe.. I probably could have saved most of the head unit..


Investing in the G3.5 soon.. (I can nickel and dime parts, but purchase $200 requires wifes approval..:))

[Mike_117]

:eek:

[PilotDane]

I only fly with wood blades. They are cheaper and shatter when they hit something which tends to do less damage to the rest of the heli. Once I learn to fly I'll probably switch to carbon blades, but that is many months away.

PS: Yes, my biggest fear is crashing my expensive heli into something that costs 10 times as much. The RADD training method preaches always keeping the heli under control, and there is nothing like flying inside your house to keep you focused and you learn to keep the heli under control and within it's "zone".

[PilotDane]

I've seen pictures of people that have been hit by carbon blades. Use wood blades especially when you are flying inside and standing close to your heli. Safety glasses might not be a bad idea (seriously). That little TRex monster will try to attack you at least once a week...

[Mike_117]

Yes, this thing has its dangers... I probably won't fly indoors for now. I marred up the hardwood pretty good and the wife wasn't happy I put a dent in her candle base.

I'll find a nice open area..(plenty in Kansas) and fly outside.
- I'd fly in my garage, but also fear of damaging my bike... .see avatar.:cool:

[leapfrog]

Ouch... bad thing about KS is the wind...

I second PD... indoors, fly woodys... period. There is enough to damage without the added whirling sabres added to the mix.

No kidding, I recently flew a SA into a stud wall on purpose (failed elevator servo... it was the safest thing to do at the time). I only had to replace the blades, the failed servo, and a canopy mount. The SA is an all plastic head... and I had the blades mounted a bit loose - they would hold themselves in the grips held perpendicular unless I "bounced" the heli. It also took me a few minutes to pick up all of the pieces of the blades (they do tend to 'splode on impact).

I fly indoors daily, but I have a bigger area with nothing to damage. Just learning, I'd recommend sticking with Radd, religiously. Keep it on the ground until control is second nature (and do the "penalty walk"... it makes you focus harder, so that you won't have to walk over to the danged heli so much, it works). And the garage is a great place to go through the first gozillion bats. How long would it take to roll your scoot out? (and the cars). A *lot* less than a single bat, I'd bet (unless it's on a lift).

I was so looking forward to discussing the G500T trims with you (it took me a bit to get mine setup)... that'll have to wait. But I am patient. *big grin*

Buy parts, learn from the mistake, grin and giggle. Not necessarily in that order...

I should also mention that I decided to replace *all* the servos on that heli - they weren't really up to the task... but that heli was built out of spare parts to begin with (the airframe was actually supposed to be a parts airframe for my other two SAs)... but I wasn't crashing, and it looked lonely sitting there in it's box. It's now happily flying alongside it's brethren... and flies *much* better than before.

[Mike_117]

..accidental post.. see next for actual post.

[Mike_117]

Leapfrog - I finally got my parts in and got the bird back to running order at least. I put woodies on and replaced most of it with stock parts except for the tail rotor mount.. blinged it.. My excuse, I ordered the 600 somehow and when went to my LHS all they had in stock was the bling:rolleyes: ..

The 500T seems pretty easy to set up. Although using factory recommendations for gain... the bird jumped pretty fierce, so I backed it down until stable.. seems to hold pretty tight. My only movement is fighting the top control.. so I'm glad I don't have to fight the tail too...
we'll see after batt 2..

Today the wind is calm so I'll take her out and practice keeping it in a stable hover. RADD method of course... If it gets away, I just want the extra room to calm it down so I don't hit anything.

[Mike_117]

Alright - another battery.. NO crashes... My gyro settings are pretty low.. as soon I adjust higher she shakes like crazy.. DX6 radio GER+39/ trv adj 13%.. I can move up the travel adjust, but I have to drop the GER setting. I also thought if you have a digital servo, you should use the hi frame rate switch? I tried and it seemed like nothing would tame it. Also the bird seems to have a delayed reaction to my right stick. I move and then it takes a second for the heli to move in flight.? probably because its a newb mistake in programming or.. the s75's suck that bad..?

[leapfrog]

w00t! Nice Mike_117!

FYI, this is my SA with the G500T (http://www.wattflyer.com/photoplog/file.php?n=1263&w=o)... I put that gyro on this bird because I was playing the the 9650 mount (http://www.wattflyer.com/photoplog/file.php?n=1264&w=o) (takes it off the tail boom). I really like the setup (http://www.wattflyer.com/photoplog/file.php?n=1265&w=o), personally... and I'm running 28%, 32% and 35% on the gain in Normal, Idle Up 1, and Idle Up 2 respectively with 100% on the rudder travel and the limiter set to full throws.

Oh yeah, framerate should be set to "HI" for the digital servo (your DS3400G)... you should definitely not use HI on an analog servo - most likely would burn it out... but for all digitals HI is the only way to go for maximum control/resolution. As for the S75s... well, they do jitter and grind... and I've had two burn out on me so far on 450s, and one on my stock Blade. But they all had at least 70+ flights on 'em. They are not as precise as a good 'ol HS65... basically, all I use on my 450 class helis anymore. The delay on the right stick may be an indication that there needs to be a bit more right aileron on the sub-trims. With your digital trims zero'd, and in a hover... will the birdie seem to seek left? That may mean that the swash is not quite level - and that can be fixed with sub-trim.

[Mike_117]

thanks leapfrog.. I'll look into this. I am on a long learning curve.. You're right on the sub trim.... .. I went back through and adjusted to try and get it as level as possible.
I am waiting on parts again. I had a broken flybar control set and thought maybe if I CA'd it for now I could fly. Well, I threw some new blades on it and took it out for a spin. I let it wind up and looked for any vibration or strange noises. Nothing, so I gave a little more and lifted up.. as soon as I made a few stick moves, the heli dipped back and fell.. I noticed the CA didn't hold and I'm pretty sure it broke mid air just before it dropped the tail.. Fortunately only a blade and the the flybar control set were broken.. now waiting for the metal parts.

[leapfrog]

Ouch... yep, you're becoming a heli pilot for sure.

I've got too many helis... and maintenance is "interesting" to keep 'em all flying... one thing I learned rather early is that it is cheaper to keep them at 100% (if in doubt, just replace the part) than it is to suffer a loss because of a "known" defect. You'll replace fewer parts in the long run... trust me. *big grin*

I'm awfully proud of you... you're on the same learning curve that we all traversed... and it is quite a ride. (and quite fun)

[Mike_117]

I went to my LHS and finally talked with someone who actually has a Trex450.. unfortunately that LHS doesn't carry a full stock of align parts. mostly a RTF blades etc store...although I will take my heli in and see if he can get this thing fine tuned better. (at least I bought my cx2 from them.. so they should be able to help..).
my other LHS down the street from this one has all the parts but no one is into heli's.
I would think the trex properly setup will lift and hover with minimal input from the right stick and should level the servos out to control the flight when returned to center stick?... just rambling.