invertedthoughts

Ifinally built up the stones to hover my Blade 400 and it was much more steady than Iimagined it to be. (Idid have the training gear on though)


Toward the end of the pack though the head started wobbling a little bit, not crazy out of control but kind of doing a bit of a toilet bowl effect thing around it's own axis. (kept the nose locked in but just wasn't as rock steady stable as Iknow it can be. Ichecked everything post flight and everything appears to be secure and fastened so it wasn't that something came loose mid flight.

Everything is bone stock, has anyone else noticed this before?


Also, is it important to have the gyro mounted perfectly square to the fuselage?When I got it was mounted cockeyed a bit which seems like it would throw it off a little.

JPEE

Inverted,

Try another pack. Make sure that pack is fully charged and balanced. If you run the battery down to low the head speed drops a bit, then that slows down the tail and you lose authority. You posted you really had more TBE (toilet bowl effect). If you were hovering to low you pick up main blade wash which will effect the heli as you stated and that might also give you TBE. Also, the higher the head speed as you lifted up will highten any main blade out of balance. If the training gear is not set perfectly and blanced to the heli that too will be a contributor and make TBE. Lastly, with the batttery in place (not connected) and canopy on, make your blades face nose to tail. The with your fingers used as slings, pick up the heli by its flybar with your fingers out about 1" from the head. This will be your centering test of the heli. If you pickup the heli and it still hangs there perfectly level you are golden. If not! there could be another reason and you need to get the heli level, move the battery around if needed.

Good luck and give this a try JPEE

invertedthoughts

Thanks for the reply JPEE, very much appreciated. Yes, the battery I think is tired as it's a few years old Esky 1800mah pack that I have had in the tool box for a while. It doesn't quite balance when it peaks (4.19, 4.19, 4.20) and seems to lose punch pretty quick. (only about 3-5 minutes of spooled up time before it hits the low voltage cutoff on the ESC. Also in doing some research I found that the blades must be perfectly matched in their grips in regard to tightness. I did the test where I turned the copter sideways and shook it, one main blade fell fairly quickly and the other one was much more sticky but finally did come down with some more authoritave shaking. So I made that adjustment and they both fall fairly easily when shaken per some instructions I found online.


I ordered 2 brand new Zippy 3S 2200mah 20C packs last night so as soon as they get here and I solder the connections on, I'll post a report. I will also check the balance as you suggested and were kind enough to post detailed pictures as well.


Thanks again, and I will post an update when I get the new batteries.

JPEE

Hello Inverted,

Forgive me, but itmight be that either you got some poor information or I am not understading what you posted. I am well aware of the blade taughtness test you performed, but the blades show not fall when "lightly" shaken and here is why. When you spool up while Horizons ESC's have a wonderful slow start if the blades move back in their grips from the motors torq while spooling the up the heli will wobble on the ground!
Here is a video to teach you the best way to balance your blades by Finless on Heli Freak which he is your mentor to learn anything you want you know and is sponsered by "every" band name of heli, servo, gyro and radio out. If you dont have a Log On there yet for this site get one, you will never regret it.
http://video.helifreak.com/?subpath=...lancing101.wmv

By the way, when you move up from the stock 1800 mAh pack to the 2250 (which is what I use) your heli will become ALIVE and will need to be totally retrimed. That new power will throw all of your settings off, just a bit so be ready. For sure your tail will drift and will have to be reset.

invertedthoughts

I'll join up at the Helifreak forum and check out the resources there, thank you for that link. What settings will I need to change? Throttle and pitch curves? Do you have a baseline I can start from by chance?

Thanks!

JPEE

Right now you should stick with a liner curve.That means the lin accross your screen in either throttle or pitch curve should go from bottom left to top right. Do you have the Blade 400 manual?

http://www.e-fliterc.com/ProdInfo/Fi...nual_loRes.pdf

Go to page 30 in the manual and you will see what I mean. Things like having out of wack pitch will make the heli come up before it should with low head speed making it hard to control. To low of pitch will have you cranking rpms way to high before you lift off!



http://www.e-fliterc.com/ProdInfo/Fi...400RTFHeli.pdf
Here is the blade pitch and throttle curves recommened. This page is in your book above too.


Here is your DX6i manual as well
http://www.e-fliterc.com/ProdInfo/Fi...6600Manual.pdf


http://www.e-fliterc.com/ProdInfo/Fi...6600Manual.pdf
manual page 105

As far as changing anything I cannot give you any recommendations because I dont know ig you bought the heli new or it is used or you have moved the factory settings. AS I said give the book a look see and see where you are now.

JPEE

invertedthoughts

Thanks JPEE, I have both the manuals and have read them both fairly thoroughly. The manual has the settings based upon the 1800mah stock battery. So when you made the suggestion that my trims will be out of whack from stock with the 2200mah battery I was just wondering if you had any "other than stock" settings to start with.


I did in fact buy it used but the guy had crashed it and then paid a hobby shop to completely rebuild it for him with brand new parts. (all Eflight parts, $70 parts/labor worth apparently). The hobby shop hovered it out in the parking lot and the original owner didn't fly it again after that. It was his first heli and he admitted that he bit off more than he should have by buying the 400 as a first heli. So he sold it without even getting to fly it again. Iwill say Ireset the swash plate from where the hobby shop had it set because they were using almost full trim on the down cyclic control to get it to trim out. When Icentered the trum the swash was out of whack. ( I think they got a little lazy here perhaps?) Anyway, the blades are tracking to within 1mm of one another which Iwas told is "close enough". ( Iknow, that term is probably considered blasphemy to use in regard to a helicopter setup)

It was put back to bone stock though. Ireally need to get a pitch gauge as I'd like to tweak that last mm of blade tracking differential and get it just right.

With the aftermarket battery packs did you stay at a 50/50 throttle/pitch curve at mid-stick?

JPEE

[quote]ORIGINAL: invertedthoughts

Thanks JPEE, I have both the manuals and have read them both fairly thoroughly. The manual has the settings based upon the 1800mah stock battery. So when you made the suggestion that my trims will be out of whack from stock with the 2200mah battery I was just wondering if you had any ''other than stock'' settings to start with.There is nothing from the stock settings you need to do other than............ simply re adjust your surface trims for the alieron (side to side) and elevator (front to back) and perhaps a bit on the tail as well. It may want to slip and bit but with a click or two of the rudder trim you'll be cool. With the power of the new battery "even though" the voltage is the same and amerage will go up so your head speed will jump up bit, all good things. Once you adjust the heli to the 2200-2250 packs you probably won't go back to the 1800 and then your trim will be out a bit. For me, it no bigger you just counter as you fly, but starting out it wont be that easy, but try it, you have nothing to loose at this point in low hovering

I did in fact buy it used but the guy had crashed it and then paid a hobby shop to completely rebuild it for him with brand new parts. (all Eflight parts, $70 parts/labor worth apparently). The hobby shop hovered it out in the parking lot and the original owner didn't fly it again after that. It was his first heli and he admitted that he bit off more than he should have by buying the 400 as a first heli. So he sold it without even getting to fly it again. I will say I reset the swash plate from where the hobby shop had it set because they were using almost full trim on the down cyclic control to get it to trim out. When I centered the trum the swash was out of whack. ( I think they got a little lazy here perhaps?) Anyway, the blades are tracking to within 1mm of one another which I was told is ''close enough''. For what your doing now, you are alright now. The whole deal is to have the blades follow each other "perfectly" so that you are not cutting through the air twice, once with each blade. Having them perfectly trailing eachother will make the heli handle better and...... you'll get longer flight times.( I know, that term is probably considered blasphemy to use in regard to a helicopter setup) [img][/img]

It was put back to bone stock though. I really need to get a pitch gauge as I'd like to tweak that last mm of blade tracking differential and get it just right.

With the aftermarket battery packs did you stay at a 50/50 throttle/pitch curve at mid-stick?
I am not following, sorry. NO matter what battery you use, at mid stick you should be at "zero" pitch. Then as you either close the or raise or lower the throttle you will incounter positive or negative pitch as it should be. Let me explain a bit simpler, I might have scared you a bit regarding the battery upgrade. It will be like putting premium gas in your car rather than regular if that helps clear things up

JPEE

invertedthoughts

Ok, thanks very much JPEE! Will post a flight report when the new batteries arrive!

invertedthoughts

Got the new batteries today and got them soldered up. (switched everything over to Dean's too)


Balanced it, and it's very good but a hair nose heavy. That's with the battery back all the way. I may need to move the ESC back a little or something to get it perfect. With airplanes it's always good to err a bit on the nose heavy side but with helis I doubt that's true as the head is everything. (someone correct me if I'm wrong please)


WOW, the new batteries are going to make this heli like a different ship altogether. I didn't get to hover it because of the wind but I spooled it up in the garage while holding it and all I can say is these batteries are going to be awesome from what I can tell so far.

invertedthoughts

Well, got to hover with the new packs and I'm a little disappointed I'm only getting about 5 minutes before hitting the LVC. I am running long wooden dowels with practice golf balls epoxied to the ends of them so I know that is adding a lot of weight but damn, I thought I would get more than 5 minutes out of 2200mah packs.


They are Zippy Flightmax. (I know, they were cheap but still should get more than 5 minutes) Could the wooden doweled training gear really be zapping the batteries that quick or do you think I just got crappy batteries? Also, the batteries are barely warm, the motor is barely warm, but the ESC is pretty hot to the touch. Problem there perhaps?

JPEE

Inverted,

There are a few factors here. When you can you should by a small Harbor Freight scale that denotes grams, oz. Then you can measure the extra weight of the training gear. Wood is lot heavier than carbon fiber rods they make gear but I would "not" suggest you go buy a store bought set, stick with what you have.

The flight time, it takes more power to hover than to fly! Why....... because there is lift from the forward motion so your times will get longer when you get to foward flight. If you ever watch a real helocopter lift off they do not lift up and go straight up, once airbourn they pull forward to lessen the stress on the copter. If I get a change I will try and fly a 400 pack and see what I get. I havent flown my 400s in more than a year

Your ESC is maxed out right out of the box. Many of us had to move from the 25 amp (as I recall) toa 35 amp like a 450 Trex has to not stress the ESC. Again, with the heli hovering no air is moving accrossed it's cooling fins so it too will get hot and feel the stress from just hovering.

Batteries: What C rating is your new battery, I know it is a Zippy, and what amperage does it say. You can buy a 2200 pack at 15, 20, 25, 30 C ratings so they will have different flight times. Also what charger are you using? the stock one without a read out that comes with the 400? What you want to know with a charger is how many mAh (milliamps) you put back in a battery after a flight. Here is some reading for you that will explain everything to you. The maximum you can fly out of a pack is 80%. So if you have a 2200 pack 8X= 1,760 mAh. So when you charge back up the battery the charger readout should NOT show that you put more than that amount back in. Like for me with 5000 pack X 8= 4,000 mAh I can take of the battery during the flight. This is not all about battery voltage it is about amps use too.

http://www.skysharkrc.com/battery_faq.htm


JPEE

invertedthoughts

Yah, the thing is, I only put back between 500-600 mahs back into each battery. I have a Sigma Pro charger that balances the cells as well. The batteries were at 11.5 volts when put on the charger, but didn't take nearly as much mah as they should have in my opinion. Which makes me wonder if these batteries can't sufficiently satisfy the power demand and it pulls the batteries down under the low voltage cutoff threshold causing the LVC protection circuit in the ESC to kick in. But then when hooked to the charger they jump back to 11+ volts without a load on them. But at 2200mah and 20C rating, they should be fine because stock batteries were only rated at 1800mah. Could it be that the Zippys aren't honest in their "C' rating? HMMMM..........????


A friend suggested I lessen the pitch a little to take some load off the motor/esc with the hopes of getting more flight time.


How much more flight time do you think would come without the training gear and mixing in scale-speed (or slower) forward flight?

invertedthoughts

Well, apparently the ESC is getting hot from hovering with the wooden dowel training gear on, so it's actually reaching thermal cutoff as opposed to low voltage cutoff.

This guy has a fix, mount the ESC on the side of the frame and really tame down the throttle/pitch curves. What do you think of this?


http://geekozoid.blogspot.com/2009/0...too-early.html




Throttle was set at:0-42.5-60-80-100

Pitch was: 35-42.5-50-75-100 (head speed was ROCKIN' at mid-3/4 stick!!)

These were setting given by Eflite for begginers on this video Iwatched:



http://www.e-fliterc.com/Articles/Ar...ArticleID=1907








I'm going to try the guy at geekozoid's numbers for hovering and slow forward flight and see how the ESCheat issue does:

Throttle:;

Position L = 0%
Position 2 = 15%
Position 3 = 30%
Position 4 = 45%
Position H = 60%


Pitch:

Position L = 35%
Position 2 = 55%
Position 3 = 70%
Position 4 = 85%
Position H = 100%


That's going to slow the head speed WAYWAYWAYdown from where I had it. I'm anxious to try it out!!!

invertedthoughts

OK, just hovered with those settings in the semi-dark. [:-]

The ESC didn't get as hot and didn't thermally shut down either but the wobble was getting pretty bad. (that's why this thread was started in the first place, right?)


So I took the training gear off and hovered it without it, WOW, smooth as silk now and I think I like that toned down head speed, much more predictable handling.

The only thing now is that when I throttle up past 3/4 throttle the tail is swinging right on me requiring constant rudder input. I don't want to trim it out because at 5/8 throttle the tail holds well.

My gyro is set at:

0: 66.5%
1: 63.5%

I was flying it in gyro setting 0, any suggestions on gyro setup would be appreciated!


(I feel like a friggin' dog chasing his tail with this thing, but it's FUN nonetheless!) [8D]

JPEE

Inverted,

I wrote your reply earlier today only to have the thread time me out so and when I hit the key to post it, it was lost to cyber space.......Arrrg So this time I'll I do it in MSW to make sure I don't lose it.

I checked my gyro and is it set at 69. Let me explain briefly about your gyro. First your 1: number should be below 49-50 so your gyro will go into "rate mode" so you can set up you tail properly. When you flip that toggle switch top left on your radio you should hear the servo zip and center itself. Now you check the tale blades to make sure they are in neutral, no pitch either way, the blades should be straight. If not then pop of your tail servos rod at the tail and screw the end in or out as needed. Also.... when you are in rate mode and the servos centers itself look hard at the servo arm it too should be stright up and down or horizontal depending the arms you have. Once you flip that back to HH Heading Hold "0" then the servo will move and the tail kind of settle at one end or the other. Once you start to spool up the gyro tells the blades how to hold you in center.
As far as adjusting your gyro you can raise that number in increments of 3-4 at a time and then see how it feels. Once the tail starts to rapidly wag or pulse left to right you have too much gain and you must back some off.

But this is what I feel is your real problem at hand. Try this and I'll bet you a dozen donuts it clears up your issues. Right now your throttle curve has that sweet spot where you can hover and the tail holds. Then with a bit more throttle past that 5/8 spot the tails start to slip. So................ try to nail down tightly just where your stick is when the tail lets go. Then go into your radio and look at the existing throttle curve which will be 0-25,25,75,100. So if you can determine let's say that you are at 70% throttle where the heli is hovering for you then level off the rest of the throttle curve to let your curve go in a horizontal direction. So you would see 0-25-50-70-70. What's happening is, when you start to lose the tail the main blades have reach a speed and torque that the slower tail blades cannot keep up with and counter. So either try what I suggested or push UP the curve so at just at lift off you are above where the tail "was" coming loose and then you can adjust to tail trim to counter. That slipping tail always happens with a low head speed. My buddy flies a 4 bladed head on a scale 500 and when you fly 4 blades you have a very low head speed. His tail was sliding too. So he took a set T-rex 600 tail blades and cut them down to a bit longer than the stock 500s and that way those would catch more air than factory 500 blades and YES it held his tail.

Just remember with the slower that head speed you lose some stability and the heli may be a "floatie" to you.

Good Luck

invertedthoughts

That makes perfect sense when you put in those terms. In other words, the pitch is creating the lift more so than the head speed, therefore the tail blades are spinning at a rate that would in usual circumstances keep the heli on the ground so it doesn't have enough authority to maintain head tracking since they are directly tied to the main rotor blades through the belt. I SEE SAID THE BLIND MAN!

invertedthoughts

I set up the tail mechanically and bumped the HH rate up to 78% and with 2 clicks of right rudder trim the bird holds it's tail pretty well at this point. I has a SLIGHT wag back and forth when I go from steady hover and pop the throttle to almost full just to test it. but it doesn't break free anymore so I'll live with the very slight wag going from 5/8 stick to around 7/8.


I also adjusted my throttle curve to be linear to 70% instead of 60%,  The ESC still doesn't get hot now because I mounted on the side of the frame as opposed to tucked away inside as it was before.

So at this point, I think I can officially say she is set up and ready to actually fly instead of tinkering with. Thanks a ton JPEE,you were a major help in this quest for a hover sir, thank you.


In all her glory!

JPEE

Inverted,

You do have a beauty to be proud of there. Sound like with your adjustments you have really gotten her on track, enjoy!

It has been a pleasure to help, my goal is make sure your having the level of fun I am with this "insane" hobby.


JPEE