KDS 600E Innova FBL

[bwoollia]

I managed to get a couple of flights in this morning before the wind came up, with good results. The first one I reduced the bar gain as a friend suggested, there might have been a marginal improvement in the tail wag so for the second flight (number four for the helicopter) I moved the ball in closer to the centre of the servo arm and tried that. Some improvement, but not perfect. I'll have to start playing with the gain, the long term solution is a replacement of the tail servo.

I did have some sort of glitch on the fourth flight, in the worst possible place. I was hovering inverted, probably about a couple of metres off the ground or less when my headspeed dropped! I punched a little bit of negative collective to give me a bit of extra altitude without losing all my headspeed and turned it over. By the time I was back in the normal hover, the power was back. I have all this on video, I'll have it up sometime today or this week.

The only explanation I can offer is the receivers on the helicopter were shadowed by the carbon frame. I have one receiver antenna sticking back and up on the rear left hand side of the frame, and the other is sticking out below the frame on the right hand side. I can see how they might have both been blanked out at that orientation, however I was very close. I forgot to check for the flashing lights before I unplugged the receiver power and turned off the transmitter, but I can't think of any other reasonable explanation. I do have another receiver at home that has two ports, perhaps I'll switch that over and run another satellite to the very front of the helicopter.

Anyways, still happy with the helicopter, and I'm looking forward to the challenge of getting that tail sorted out!

[bwoollia]

Second and third flights:

[snooze98k]

I hate to ask, But how the hell do i use this 8amp UBEC supplied by kds?
Input requires a 2-3cell battery. Well, i haven't found Anyone who uses a reciever battery for this Innova, nor do i want to go out and buy a proper rated ubec :|

[bwoollia]

I am using an 1800mAh 2S 20C battery as my receiver battery. Do you know of anyone who isn't using a separate receiver battery on a helicopter this size?

[wonderd]

Does anyone know if the servos are capable of taking a 2s lifepo4 batt.?

[bwoollia]

No they're not.

[wonderd]

Why not? - 6.6v is too much for them?

[bwoollia]

They're spec'd for 4.8V, I'm running mine at 6V: http://www.servodatabase.com/servo/kds/n690

[bruno95]

N680 & N690 are Rated 4.8 - 6V.

Checkout the servo spec given with them.

N690:
Output torque: 4.0 kg (4.8V) / 4,5 Kg (6V)
Speed: 0,07sec/60 (4.8V) / 0.06sec/60 (6V)

N680

Output torque: 10 kg (4.8V) / 12 Kg (6V)
Speed: 0,09sec/60 (4.8V) / 0.08sec/60 (6V)

I'm running mines direct connected to Life 2S 2100 (6.6v)

Regards.

Bruno

[bwoollia]

Thanks for the info, Bruno!

[JeremyT]

Hi bwoollia,

I am also right within the process of building my KDS Innova 600 FBL.
Frame, rotor head, tail are completed, the wait is now for a receiver and 2x 6S LiPo's to run in series.

There is one thing that I am not sure about.
When spinning the main rotor head (no main blades installed yet) there is some resistance coming from the belt while it's driving the tail rotor assembly.
Everything does spin together, so it has been assembled properly, but the belt definately doesn't run it all 'silky smooth'.
At a certain point of the belt's 'coming by' the belt's resistance becomes even higher. Continue to spin the main rotor head and it becomes less fast, but briefly comes back over and over again when I pass that point of belt again while spinning.

The belt is twisting only one time inside the tailboom as it should, and the tail rotor is spinning the right way. To be absolutely sure I have dis- and reassembled the complete tail to check it over.
The belt also is not too tight. As a matter of fact, if I slide the boom in a tiny bit more from this point, it already becomes too loose and comes off the main driving gear when spinning.

Maybe it's all the way it should be on a 600 (it's my first 600) and is it no problem for when the motor drives it all. But for example, would this resistance be a potential problem for autorotation?
Or does the belt just needs to be 'worked in' and is it just a little stiff because it's new?
It is just that in my 450 when spinning the main rotor by hand the belt gives no resistance at all.

Thanks!

Jeremy.

[bwoollia]

My belt was similar, and still does that a bit. It definitely drags more in some positions than others. The head will spin around quite freely for a couple of turns then the next it slows down a bit. There doesn't seem to be any adverse affect once things are spinning, and I have done several autorotations from altitude. Just adjust the tension as you normally would. I think the issue is that the belt isn't 100% "straight" - it has a bit of a wiggle to it and the resistance is from it settling into the gears. When it's running with tension this seems to go away - there is no evidence of the belt wearing unusually.

This effect seems to be reducing - I think it may have happened in storage and is working out.

[JeremyT]

Hi,

Thanks! That was pretty much the answer I was hoping for.
If I may ask you two more questions:

What receiver are you using and do you have the KDS 8A UBEC going to the receiver only (powering receiver and all 4 servo's through receiver) or do you use an external power bus?

I am planning to use a Wallera RX-2801 Pro together with the KDS EBAR, but I'm not sure if it's 100% safe to pull all the needed servo Amps through it, by only connecting the UBEC output connector to the BATT input port of that receiver.

Second: does the 500KV KDS stock motor really need 12S, or can you also use a single 6S pack?

Thanks a ton!

Jeremy.

[bwoollia]

Originally Posted by JeremyT

Hi,

Thanks! That was pretty much the answer I was hoping for.
If I may ask you two more questions:

What receiver are you using and do you have the KDS 8A UBEC going to the receiver only (powering receiver and all 4 servo's through receiver) or do you use an external power bus?

I am planning to use a Wallera RX-2801 Pro together with the KDS EBAR, but I'm not sure if it's 100% safe to pull all the needed servo Amps through it, by only connecting the UBEC output connector to the BATT input port of that receiver.

I power the 8A UBEC with a 1600mAh 2S lipo, it goes into the battery port of my 9ch Orange RX. You shouldn't have an issue with your receiver, the servo power doesn't go "through" the rest of the receiver, there should be a + and - strip that connects all of the servo connectors.

Second: does the 500KV KDS stock motor really need 12S, or can you also use a single 6S pack?

I wouldn't try to modify it to work on 6S. I'm guessing that I'm pulling 80-100A (really guessing, I don't know) through my power system, to get similar power on 6S you'd have to double whatever I run. So you might save a little bit by buying only one, larger 6S battery but you'd have to pony up for a much larger ESC. Even then, your batteries would tire much sooner at those power levels. Not to mention that you'll need a new motor to provide the headspeed required. Essentially, you'll be paying more money to have an inferior power setup.

6S batteries aren't that expensive anymore. I bought two sets (pairs) of 6S batteries from different brands, each battery was less than $60. Here are the batteries I am using:

http://www.snhobbies.com/product_inf...oducts_id=3427
http://www.snhobbies.com/product_inf...oducts_id=3454

Thanks a ton!

Jeremy.

Good luck! Keep us posted with your results!

[JeremyT]

Hi,

Thanks again!
I will continue my build and will keep you posted.

My 2 6S LiPo's came in today.
I was planning to put EC5 connectors to them, as well as to the stock KDS 120A HV ESC.
Something you'd say to go with, or is it better to stick with the 6 mm bullets that are already on the LiPo's? May I ask what you have?

I first need to find a way to charge them anyway, as their balance plugs don't seem to fit in my charger. There's just a very tiny difference in the plastic shape of the plug, so I guess I need a converter cable pf some sort.

[bwoollia]

I'm using 6mm bullets: http://www.hobbyking.com/hobbyking/s...dproduct=20353

EC5 connectors should work well too. Are you using Hyperion batteries? They have a goofy balance connector too.

[JeremyT]

Hi,

I have found myself a balance board that fits my new 6S packs and connects to my charger on the other end.
I guess I'll stick with the 6 mm bullets and will start with soldering the series cable.

What LiPo (specs) *do you use for the flight electronics, and where have you placed it while flying?
With some 2S packs I have just enough room left to place it either on top or next to the 6S packs, but is that ok if the battery 'bodies' are touching due to potential heat generation, etc.?

Thanks!!

[bwoollia]

I use a 1600mAh 2S 20C battery: http://www.hobbyking.com/hobbyking/s...idProduct=7370

Mine is strapped on to the top of my front 6S battery. No heat issues, really but I've only been flying mine in cold temperatures so far. I don't anticipate much heat anyways. There are six cells touching each other just below it!

[JeremyT]

Hi,

Did you also find that the EBAR manual is incorrect about the EBAR mounting position and the corresponding orientations in the PPC unit?

In my EBAR CH1: elevator servo, CH2: right servo (top view, nose pointing up), CH3: left servo (top view, nose point up), CH4: rudder.

The EBAR is mounted on the upper back plate of the Innova 600, with the ports facing to the rear/tail.
My orientation setting in the PPC unit is "REAR" for swashplate setting "HR-3".

The swash moves in the right directions when banging the cyclic stick on the transmitter. Giving positive and negative pitch also moves the swash down and up the proper way respectively.

When I tilt the heli in all directions, the swashplate shows the correct opposite movement.

Yet the EBAR manual says the way I have installed the EBAR has to be set as "FRONT" orientation in the PPC unit.

Manual error?

[Adventurer]

Originally Posted by JeremyT

Hi,

Did you also find that the EBAR manual is incorrect about the EBAR mounting position and the corresponding orientations in the PPC unit?

Manual error?

Yes, the manual is wrong withe regards to the orientation of the EBAR, simply swap FRONT and BACK and it works.