I'm confused Raptor 30 with a gy401

[ronn1234]

First of all I have about 18 flights on this bird and I love it it is very stable. Here is my question though I have been having this problem with the tail with the nose pointing away from me the tail drifts to the right or counter clock wise well I have been ajusting the servo rod and I just about have it dialed in. I have also been ajusting the limiter on the gy401 to prevent any binding. Now with the tail near perfact when i give left rudder input the slider does not move all the way out to the tail fins like it used to. Mind you to dial in the tail I had to basically turn in the 2 ball link connectors as short as they would go, effectively shortning the control rod now this effect makes sence to me that it cannot push the rod as far as it used to but do i need the full deflection both directions if i do then how do i accomplish this. If i lengthen the rod back out then i will get the counter rotation again. I have a spectrum dx7 my travel adjust is set left at 85% right at 100%.

[Skiddz]

Sounds like the mechanical linkage isn't correct. End points on the rudder channel are not for setting servo travel limits. They set the pirouette speed. (i.e. how fast do you want to allow the heli to rotate) Have you mapped the GEAR or AUX2 channel to the gyro gain, or are you using endpoints on the channel to set gain? What's your headspeed? Since the heli is rotating counterclockwise, the TR isn't compensating enough for torque which may mean it's not spinning fast enough. HS is directly related to TR speed. Do you have any trim dialed in on the rudder channel? Not subtrim, regular trim? That'll present itself as a drift as the gyro will see that as the new center when it initializes. Are you in HH mode?

This video will get you dialed in on the 401 mechanical setup and has some good info on gains, ATV etc..

http://video.helifreak.com/?subpath=finless/trex450&filename=gyro_setup.wmv

and this one will show you how to set up the gyro on a DX7:

http://video.helifreak.com/?subpath=finless/generic&filename=dx7v3.wmv

Lastly, there are a TON of posts about setting up a 401 with a DX7. The search function would do wonders while you're waiting for the videos to download.

Good luck.

[ronn1234]

I have no idea what my head speed is I donot have a tach. yes I have the gear channel set up for HH and STD I am useing about 85% gain in HH. So I am correct in thinking that I should have full left right range on the tail IE the slider should go completely from the tail to the fins. One thing i did notice even with the rods disconnected, both left and right directions of stick movment after about 1/2 stick the servo dosn't move any more it is at it's full travel distance I also have the limiter set to almost the minimum possiable. I donot have any trim in the rudder sub or reg. I have watched that video and that is how I set mine up. could it be that i had to reduce the length so much because i didn't start off with the slider perfactly centered?

[Skiddz]

So, you're using end points on the gear channel to control gain? Or are you using the GYRO SENS menu in the Tx?

Servo movement like you're seeing is normal and when the gyro is in HH mode, it will not center on its own.

You want to set the ball link on the servo horn so you get full travel of the slider with the limit pot on the gyro as close to 100 as possible. Tweak the linkage length or move the servo around on the boom to stop binding in both directions. Once you get that done, the slider is centered properly and you can tweak gains etc and go fly.

[ronn1234]

Just an update here. A gentelman at the flying field clocked my HS at 1450 rpm max it was 1550 he said that was plently fast enough. I decreased my gain with endpoints on gear switch i was at 84 for HH like raptortech suggests. the guy at the field told me to lower it to 40 and bam spot on with a throttle curve increase from 18 50 60 70 100 to 18 53 65 70 100. I do have another question though when I try to increase my HS through Throtel curves I get a situation where it seems the tail trys to over speed least i think it is over speeding it generally hapens at 50% throttle in a hover when i give back cyclic input. I'm gona try to describe it it, it makes a wa wa wa wa sound along with a strong vibration or wobble i can see the tail fins moving (could they be to loose or to tight) it is only in the tail and only sence i increased my throttle curves so i decreased my throttle curves and the tail dosn't hold the nose drifts left with the tail facing me but the wa wa wa wa thing is gone. I am at a loss here. Because won't this just get worse if i try to take it to the recomended 1750 rpm. oh question how the heck do i get 1750 rmp that is a huge diff from what i have now. I have an os 37 sz motor my pitch curves are -2 3 6 inh 9 on a DX7 controller. the guy at the field said the wa wa wa wa effect was because my engine is to lean at mid stick but after the flight i can leave my finger on the back indefinatly which i have heard that is too rich. I'm so confused.

[ronn1234]

no ideas any one

[StringfellowHawk]

You should only be able to hold your finger on the backplate of your engine for a few seconds. So if you can hold it there indefintely you might want to retune your engine.

I have the OS37 engine as well. If you look in the manual that came with your 37 you will find the default mixture screw settings. Go back to them. Then slowly (2-3 clicks clockwise) lean out your mixture screw, test fly and then if you can still keep your finger on the backplate repeat. If it gets too hot, go counter-clockwise two clicks and check it again. Never go more than 2-3 clicks at a time. And make sure to check the backplate quickly after landing (make sure to stop the blades safely, please).

Keep in mind that you can do a search on this website, among others, and get a lot of good information about engine tuning. It's more of an art than science, so don't get too discouraged. And remember that you will have to retune your engine for different fuels, temperature changes, climate changes, etc. Once you get the hang of it you will find that it doesn't take as long as the first time.

Retune your engine and let us know.

[ronn1234]

My engine was running at 230 degrees and the guy helped me tune it to get it to where it is now it really sounds allot better not as high pitched but it don't have any climb power. For example that day it was kinda windy and when the wind lifted the heli as it blew when the gust went away and the heli droped i had to go full throttle just to keep it from hitting the ground then it's like every thing caught up and up it would go. Also it seems to be useing more fuel atm than it was when i was running it at 215-230 degrees I give that range cause it would sometimes be 210 225 230 never concistantly the same. Oh I should note that before he richened it he clocked the head at 1650. As he tuned it the headspeed dropped. I'm thinking this thing should have allot more power than it does but i'm scared to over heat it " I have lots of experience workin with airplane motors but the heat isn't an issue with them and they run lean. Btw I am running CP 15% heli fuel the guy in the lhs said to breakin the motor and later run CP 20 or 30.

[ronn1234]

Oh one more question for you string you have a raptor 30 right what is your gain at in HH and what are your throttle pitch curves.

[StringfellowHawk]

You really can't go by temperature alone in tuning the engine. Read what OS says about engine temperature:

http://www.osengines.com/faq/product-faq.html#q14

If the motor has not be broke in yet you will find that power will be lacking. Follow the break in procedures that OS gives and then try tunning for power. It took mine about a gallon of fuel (running slightly rich) to really come up to speed. Then I could tune for power.

I have a JR Venture 30 but it really doesn't matter. Unless the two helis are identical twins the gyro gain values will be different. But to answer your question, I am running about 68% gain in HH mode. I really recommend you watch the videos Skiddz suggested.

The basic throttle curve in normal mode to get you started (for a 5 point radio like the DX7) is:
0 23 38 50 100

Remember to use 0 so you can shut down the engine if you need to. If you set it to 0 you can use your throttle stick trim to set your idle point. Mine is usually a tad under center to start the engine. Then, when you want to cut off the engine you can just click your throttle trim all the way down. If you've set throttle recovery on the DX7 the next time you want to start up the engine you can just push the throttle trim up once and it will go back to your last throttle setting.

pitch curve (remember to use a pitch gauge on your blades to find the values you need):
-2.5 -2.5 0 5 10

This should hover you at 3/4 stick. To get the best performance, you will need to work with these values for your particular setup.

Besides the great videos that Bob has provided (among others), I would also recommend the book "Ray's Authorative DVD Series: Shop & Field Companion". Between these two resources you will find that almost all of your questions will be answered.

Phew! I hope all of this makes sense. :)

[ronn1234]

Ok,
Thanks for the help I have ran 3 gallons of fuel through mine so i think it is broke in. I just went to the OS site that is very interesting "No right Temp" my engine was really purring when the temps were around the 230 temp had lots of power. I think what I will do is lean the HS a bit and richen the low speed. and see what I come up with. I found some information on my WAH WAH WAH issue on raptortechnique there are 3 things that can cause it 1st lean low end, 2nd main gear has up/down play "which mine does have just a tiny amout of. The sight said to place a shim above the maingear inbetween the C ring and maingear, or the 3rd solution go to a Driven tail which I have heard that due to bleed off in autos I don't really want that. So I will work the engin tooning first as that seems to be when it started when the first fella (airplane guy ;) ) that helped me leaned my low speed out and richened my highspeed. So when I do get the engine tuned properly how do i get the headspeed higher? increase the throttle curve?

[ronn1234]

ok I flew about 6 tanks tonight here is what i came up with

Gain on gyro 36% nose moves left ever so slightly like it will stay in one spot for 30 secs or so then it will move just a little but i think it may be cause i ride the throttle constantly IE I am always ajusting it at hover but when i apply power it seems to lock in very well.

Throttle curve: L 18% 1 45% 2 55% 3 65% H 100%
Pitch curve: (L 31% for -2) (1 INH) (2 70% for +5) (3 INH) (H 95% +9)

Tuned the engine so that it is semi warm can keep the finger on it for 3 secs max maybe but if i go a click richer my stick is out of position for where i'm suppose to be at hover. throttle does not bog from low to mid stick and there is very little RPM change from middle to 95% keep in mind from hover i gun it to 100% for bout 3 secs and the heli lifts quickly and i am afraid to leave it at max throttle for long hehe only bout 28 flights under my belt. The WAH WAH is gone when i reduce throttle it does not occure. I'm sure that it could maybe be fine tuned more by an expert but when i move it any leaner it gets too hot and any richer it boggs down. I was ajusting the low end and the high speed, does it sound like i got it. Oh before when i was say 20 feet and did a fairly rapid decent the heli would barly recover in time now i just bump the throttle up and it recovers fairly rapidly in say 4 ft where as before it would require full throttle. BTW my goal is to hover at mid stick as Raptortechnique reccomends and it hovers just barley past mid stick.

[StringfellowHawk]

my goal is to hover at mid stick as Raptortechnique reccomends and it hovers just barley past mid stick.

It sounds like you are starting to get things straight.

An easy way to test the low end needle on the engine is to pinch the fuel line going to the carb while at idle. If the engine dies immediately, your way too lean so give the low end needle a 1/8" turn CCW and repeat. If the engine takes longer than about 3-4 seconds to die (it will start the speed up and then die, this is normal because your leaning the engine) turn the low end needle CW about an 1/8" and repeat. You will need to do this every time you adjust the main needle, so make sure you get the engine running nicely and then do this.

Gyro gain won't fix nose drift. It the tail isn't wagging, your gain is probably pretty good. You may need to adjust your rudder linkage a bit. If it isn't centered this would cause a slight drift of the nose one way or the other. Also, make sure your rudder trim is centered on your DX7 as well.

You might want to change your throttle curve point 3 to be 75% instead of 65%.

Otherwise, I think your making progress.

[ronn1234]

My tail was set at 4.5 mm from the case in rate mode the nose turned left so i shortened the rod in rate mode now the heli dosn't move much at all only with change of power i flip it to HH and it does what it does previously stated to be honest in a hover it is hard to tell a diffrance when flying rate and hh except when applying power the tail don't move when in hh BTW the nose drifting left is what originally started all this it was driving me crazy constantly had to give right stick to adjust when i tride to increase my HS as suggested by some one else it cause all these other problems.

Thanks for the low end Tip that will help tons

Exactly how locked in should the tail be i am useing a 401 gyro should it move at all

[Skarn]

Couple things: Your L setting on throttle curve should be zero as string stated...that way with trim, you can cut your motor if needed. At 18%, the motor will never cut off.

As far as being in HH mode....the tail should not move unless you command it to. You said your gain is at 36%? Are you using the gyro sense menu or gear ATVs? If using gyro sense, that is rate mode...anything above 50% is HH mode.....is the light on your 401 lit solid red?

Skarn

[ronn1234]

I have a dx7 controller and it has throttle trim skill switch and I am useing the ATV not the gyro sencesetting.so if my nose moves to the left with the tail facing me do I need to shorten my control rod one turn at a time in rate mode, however in rate mode the tail is pretty solid except when i apply power and decrease power. And when I do that do i need to reset center IE flick the gear switch 3 times.