dunkonu23

Tail kick...

During this morning's pack break in, I got tail kick again during pitch pumps in idle up.  I dunno if this is a problem, but the tail kicks about 90 degrees during a full pitch pump.  It would probably go more, but at that point the helicopter is already higher than comfortable for back yard flying.  I don't know if this is a problem because at the Mid America Fun Fly, when pros did full pitch takeoffs straight up, they got rotation, too.  So, I'm gonna ask if any of you have done full pitch, idle up take offs and if so, did you get tail kick (mine moved to the right, nose left)?

Scott

noobflyer01

wish i could help you with your gyro Scott.   I have the align gp750 and the tail is locked solid no matter what I do.  

Make sure you're at 0 degree pitch at midstick and getting no more than +13 degrees on top.   

dunkonu23

No problem, Noob. I'm at zero pitch at midstick and at 13, -13 in pitch. I had a thought. When I programmed my ESC, I changed the throttle response to slow. What's your throttle response, Noob? My thought is that even though at mid stick in idle, I'm at 90% throttle, Ihave 10% to go and at slow the sudden change in pitch may cause a bit of bogging that shows up in a tail kick.

Scott

noobflyer01

i'm checking I'll be right back with the answer, Scott.

noobflyer01

throttle response is 5 beeps. i have mine at the top(high stick)for quick or fast response. make sure you program the esc's high stick and low stick with a linear throttle curve (0,25,50,75,100)

btw...i waiting for the ups guy to drop my package off. package is out for delivery

i wish he hurry up so i can put it together. got me a exi 450 metal head edition.

dunkonu23

Thanks, Noob! I'm sorry I didn't get back to you sooner. Ireally appreciate your going the extra mile for me!

One of my friends, Olwarbirds flys an EXI helicopter. I hope yours is every bit as good as his is! Enjoy your build, bro!

Scott

J-MICHAEL

Scott ~

There's a few things that can contribute to that. If its bothers you, just keep tweaking at it and you'll get it. I use the GY401's on all my heli's and there locked in solid with no tail kickouts during punchouts. The quality of the gyro/tail servo is the main factor, then how its set-up etc. If your running a low gyro gain, you'll tend to get a bit more of a kickout depending on your settings. I like to have my TX gain for the gyro sensitivity at around 72%-75%, but that's just my preference. Others, who are more into 3-D may want a looser tail and using less. The few guys you saw who were having there tails kick could have been in rate mode perhaps ? Just a thought... I know some Pro's fly in rate mode and so I wonder if that would be there cause ? Dunno...

Also just make sure your not running to low of a throttle curve in conjunction with to much pitch. That will contribute also a bit...

Boy, I haven't flown my T-500 for awhile as I've been focused on my other heli's ! But I've been browsing the thread here keeping up whenever I can, just nothing to contribute yet... Hopefully soon ! I miss my 500.......... Its been sitting collecting dust dang it ! I can't wait to try out these 430mm CF SABS that come on the Protos. My last crash resulted in the Align CF's to shatter.

Another thing is, like Finless has said in his Trex 600 Torque-Tube set-up video, is to ALSO pin your TAILCASE....And then the boom of course also that everyone seemed to have done. Because like he says, he's seen them fly off and has had it happen to himself. There's just not enough there to keep it on snug if your throwing a lot of torque into it out there. The V-fin holes set into the boom and the couple of fasteners aren't adequate when your flying at the next level. I did mine just to be safe... Just some FYI...


My last video with the Trex 500 using the GY401 will show me doing some punchouts, or full collective (almost) spikes, and the tail is locked... Its only 3 minutes long, and you may have seen it, but it ended up being my first crash with the 500. Not bad since I've now had it 8 months though... That crash was about $185.00 ! Yikes !




http://www.vimeo.com/4806547



For another comparison, but looking at it as a mini-T-500, () is my Trex 450. My last video with that is below in the 4 minute video testing out a Scorpion motor. I have a tad of kick, but not much as you see me spike it around a few times.... Still some more tweaking to do, but generally I'll just let it slide and fly it like it is. If its close enough, I'am fine with it... This video is a little better since I got a better cam for the hatcam set-up, along with a better site to broadcast the video. Just push play...



http://exposureroom.com/members/J-MI...e37a79f7096b6/



I need to get my T-500 back out there and join the fun here !

dunkonu23

Thanks, J!

Gotta love your choice of music in video's. Thanks! I'm held up on my digital camcorder waiting on reward points redemption. I do see from your video's and Noobs videos too that y'all don't get tail kick. Great setups! I'm sorry about your crash. I'm dreading that day here. I've been reading what other people break and ordering spares based on that, and my BH500 experience.

Iappreciate your taking the time to post all you did! As I've posted elsewhere, I'm a tweak freak, so Ido tweak things constantly, and Ithought I had the tail kick thing beaten by moving the link to the innermost hole, but alas while it fixed drift, it didn't do much for kick. I do think it's an RPM/loading issue as you alluded to with your Scorpion motor. So, today I'm going to change the ESC programming and go over pitch again. Ido know it's at zero center stick and when Ilast checked pitch was 13 -13, so checking again will probably reveal something; even though the setup seems spot on from a hovering perspective. Gain-wise, I'm at about 74 on my DX7 with my Spartan gyro and JR 8500G tail servo. One more click up and I'll get wag. One thing that has me a bit bothered is the amount of throw on the servo. My endpoints are set at 100/87 (one clickmore binds)and the Spartan manual recommends a combined setting over 200. But that's related to link/horn placement so I may have to use a new horn to get over 200 total throw. I setup themechanicalaspectin Rate mode and haveno drift at all in hover while in Rate Mode, so that's a good thing. I will check that again.

As far as the pros go, you raised a good point. I didn'ttalk to them to find out if they were inRate mode during theirpunch out or even if theyput some rotation in for dramatic effect.I'll just stick to trying to lock it in. :-) I will say that I get absolutely no wag or drift at all. :-)

Thanks gain, J!

Scott

J-MICHAEL

Scott ~

I'am certain you'll get it... Very nice Spartan and JR combo I will add though ! [8D] That eliminates the quality issue. (LMAO). I'am not familiar with the Spartan gyro, as my first gyro was the GY401, and then kinda just stuck with using those since I'am familiar with them and they do good for now at my stage of the game.

I know the 2 gyro's are different, but I'll give you my settings anyway and maybe there's something there that could be similiar ? Dunno...

I'am using a Futaba 9254 tail servo on the Trex 500, and the distance from the center of the servo arm to the link is 10.36 mm. (Picture below). Then on the gyro itself there is a "limit" pot for travel adjust. I have mine set at 84%... The 401 gets its best resolution between 80-100% app. Then there is a switch for digital or analog servos, and of course I'am running it in digital mode. there's a "Dir" switch if I need to ever reverse that, and there is also a "Delay" pot, which on all my 401's that is set at 0 which is also recommended by Finless when running a digital servo.

Then the last thing is my settings in my DX7, in which my gyro gain is set at 75%... I've been at 80% with no wag when I first was getting used to her, but then as I've slowly been learning forward flight I've reduced the gain now to 75% to help loosen the tail a bit more when I'am swinging around in a corner for instance, to help make it look and feel more natural.

I wonder if Finless has a set-up video for the Spartan ? I'am betting maybe ? But not sure.....



Have a good one,

~ Jeff

dunkonu23

Thanks Jeff!

You really took a lot of time to help and Iappreciate it, big time. Taking all those measurements and pictures must have taken some time.

Ijust finished redoing the ESC (now in fast throttle response) and pitch (13 -13, cyclic 9 and -9) and tested it. It reduced the kick quite a bit. In fact, on more than one punch out, it didn't kick, so I'm thinking I'll increase the rudder deadband some to eliminate error on my part. I was kind of lucky because the wind is kicking up big with gusts to around 30mph, so even though the helicopter performed well, I'm not going to stop until the wind dies down.

The gyro has a USB interface and software so I can program it, deadband is one of the adjustments. It's interesting though. If it's not me, it would seem that the gyro is over correcting because the kick (or my error) is nose to the left, tail right. If it was under correcting, I would think the kick would be nose right, tailleft.

Yep, Finless has a setup video. I've watched it several times during the gyro setup and I can't see where I've got anything different other than the high and low endpoints.

Thanks again, Jeff!

Scott

dunkonu23

I found this is Spartan support.

15. The tail kicks to the right when I suddenly increase the collective.
This it typically the result of low gyro gain, slow tail servo or tail mechanics that are unable to provide enough thrust to compensate for main rotor toque.

Try increasing the gyro gain as high as you can reach without and tail wag seen at any time during flight. A slow tail servo, stiff push-rod or faulty tail grip bearing may prevent you from reaching the optimal gain value for your helicopter. On these grounds it should also be noted that the S9650 servo that has been a popular tail servo choice in past in 450 size helicopters is not fast enough to bring out the best performance from your Spartan gyro.

If the helicopter has been fitted with a significantly more powerful motor than the helicopter manufacturer's recommendation and the collective range gas been increased it is possible that the tail may not be able to provide enough thrust to compensate. If enough clearance is available between the main and tail rotor, try fitting longer tail blades.

Finnally, it should be noted that some ESCs with build in governor create an irregular/delayed response resulting to such tail kick on sudden collective changes. Disable the governor function and observe in the problem persists.

noobflyer01

I sure hope you get your gyro sorted out Scott.

I just finished my EXI450 build today. Just took her out in the driveway for her maiden flight and happy to report she's flying awesome. Here's some pics. NOTE: the tail boom and everything on it is upgraded to align parts.

dunkonu23

Looks great, Noob! How's the tail? LOL! Easy build?

In my case, I'm done for the day. Three packs, moving ball links, adjusting tail endpoints, removing Chinese weights. No drift, just a kick.

Scott

noobflyer01

I had the metal tail for a while when i had the trex450sa and wanted to upgrade the tail. I just never had a chance to install them until now. Since its brand new its smooth as butter.

My last crash with the Poseidon was worst than I thought. I went in pretty hard. http://www.youtube.com/watch?v=2_47S...e=channel_page as you can see in the video. I just had to try backwards inverted flight for the first time. Ihad practiced easily on the sim for a while and had to try it for real. It wasnt a totally lost since I learned plenty on that 2:30 minutes. Igotta keep trying.

Repairing the Poseidon was easy.But i think that last crash really messed up the all the bearings and alot of the head. Ijust couldnt get her to track. Instead of getting more spares Igutted her and used them on the new EXI450.

Here a break down of the EXI450: JustGoFly 500TH w/12T, Align 35a esc, hs65mg cyclic, futaba gy401 with 9257 tail servo, flightmax 2200mah 3S 25C, align boom, align carbon fins, align boom supports, align tail blades, align metal tail complete, carbon tail servo pushrod. fiberglass canopy. Tail is holding ROCKSOLID!

noobflyer01

I will do a video tommorrow on my new victim......er I mean my new helicopter. lol   This one is unlike alot of my previous helis.  She is really smooth and tame.  so quiet.   She doesnt have that  " I'm going to Rip the sky attitude".....but we'll see tommorrow.     I expect LONG flight times with the current setup.  maybe 6-7 minutes per pack lol....I'm so used to flying ballistic for 4 minutes per pack.

noobflyer01

here's some more pics. 450 and 500 size comparisons.

dunkonu23

Hey Jeff,

Did the S9254 fit in the standard mounting bracket?  Just wondering because I may have to consider a different servo.

Thanks!

Scott

dunkonu23

It looks really cool, Noob.  But man, gutting the Poseidon!  I really like those helicopters.  They're different and it's a shame you crashed! 

Scott

J-MICHAEL

Noob ~

Dang sorry to see the Poseidon go down like that. I'am liking your new EXI 450 though ! [8D]


Scott ~

For using the standard size servo like the 9254, I had to use a mounting bracket from a Trex 600. I got the idea when like you, I was wondering how they were fitting them on the 500, and heard that most will just use the 600's bracket. Its worked great, and I just use the CNC mounts from Microheli. The stock ESP CNC mounts should also work just fine...


~ Jeff

dunkonu23

Thanks, Jeff! One more question: How do you handle its weight in terms of CG?

Scott

dunkonu23

Well, I went ahead and ordered a 9254 and the TRex 600 mounting stuff just to be on the safe side. If it turns out I don't need them, I can always sell them...

Scott

noobflyer01

that's a pricey tail servo Scott. its nice.  but your JR 3500 should be plenty good for the ESP.  Not sure why you have a tail quick.

I'm loving my new 450.  It seems i lost my memory card for the camera.  I will have to buy a new one on friday.  should be cheap at best buy on black friday.  I will try to get a video up on friday.  

getting 6 minutes of flight with 100% throttle curve on stunt.   I was able to pull off flips and rolls with easy and precision.  all it needs is a good set of carbon blades.

dunkonu23

Sounds good, Noob! I like watching your videos and thing... wow... he makes it look easy. One day, I'll be at your level.

In the meantime... today, I found a problem. I'm not certain it is the problem, but it's a problem. I've got a tiny amount of play in one blade grip. I've ordered replacements and they should be here tomorrow, along with the new servo.

Scott

dunkonu23

No luck with anything so far. Changed grips, no change. Longer blades, no change. Swapped servo to 9256, no change. I'm out of options.


Jeff did you also use the standard tail push rod guides to get 10 mm? On the 9256, I can only get 17 mm because that's where the link falls naturally. Just wondering.

Scott

KCinNC

my 500 ESP was suppose to be here Friday........but i missed the UPS guy by 35 minutes [] i was ALL excited to start building this weekend. now gotta wait till next week !