Brushless Lama V4

[tomfn]

I already had the DX6 and the DX6 is programmable. The DX6 reciever is much smaler and lighter than the stock 4in1 reciever. With the stock radio i could not change the trottle curves, with the DX6 i have the trottle curve set to 0-60-100. At 60% trottle the stick is in the midle and the heli hovers.

[MTBikerTim]

Hey tomfn

Your post has been awesome in helping work out what I need to make my lama brushless.

My two reasons for going brushless are that my almost fully extreme v4 can barely get it's fat arse of the ground currently and that I'm bored since I don't have a bigger heli to play with. My v4 used to be a v3 but I went to v4 when I bought all the extreme upgrades. The only part I didn't get was the extreme frame and I may get that eventually too. I know most of the upgrades are useless but I did it for the cool factor and once again for something to do over christmas since my Trex 450 never showed up. Now I'm waiting for the pro so in the mean time the v4 is getting brushless.

All the parts I need to make my v4 brushless arrived in the mail today. Can't wait to put it together and hopefully it will work.

The parts I'm going to be using are:
DX7
AR7000 (temporary until I can be bothered ordering a 6100 or 6100e)
Futaba 401 (temporary but it's what I have sitting here)
2 x Castle Thunderbird 6 speedy (no idea if these will work but I have heaps of castle speedies in my cars and like them)
2 x ELE C10 2900kv motors from Strong RC Motors (Don is a legend)
GWS V-Tail Mixer II v2.1 for JR (Should I have gotten the futaba one, so confused as I have a jr radio and futaba gyro?)

So hopefully this setup will work and keep my heli airborne for longer then the 30 seconds it currently flies for.

[tomfn]

Hello MT Biker

Glad to hear that my post was helpfull. The Thunderbird esc will and the GWS mixer will work fine. The 401 is a litle bit heavy (27gr), the MK191 is only 4,8gr but i think it will work fine. I tried to keep the weight as low as possible when i picked the parts. I have been flying over 50 flights since the conversion and have only changed one skid :-) Before the conversion i had to change a part everytime i had a crash. Its winter in Norway and -15degrees so i fly alot around the living room. (my wife is very happy when i fly over the table and blows out the candles.....) And it is a lot more fun to fly with 13 to 14 min.flight time. Tail is rock solid....

Good Luck with the conversion, and sorry for my english :-)

[MTBikerTim]

Originally Posted by tomfn

Hello MT Biker

Glad to hear that my post was helpfull. The Thunderbird esc will and the GWS mixer will work fine. The 401 is a litle bit heavy (27gr), the MK191 is only 4,8gr but i think it will work fine. I tried to keep the weight as low as possible when i picked the parts. I have been flying over 50 flights since the conversion and have only changed one skid :-) Before the conversion i had to change a part everytime i had a crash. Its winter in Norway and -15degrees so i fly alot around the living room. (my wife is very happy when i fly over the table and blows out the candles.....) And it is a lot more fun to fly with 13 to 14 min.flight time. Tail is rock solid....

Good Luck with the conversion, and sorry for my english :-)

Yeah I will get a smaller gyro like the mk191 and smaller receiver too. I hadn't even pulled my 401 out of the box, now I have I realise just how big it is. I will move it to the 450 when it arrives and get something a little smaller then.

I have it together, still tweaking though. With 0 throttle the blades will still spin due to the gyro. I still have to work that one out. Back to testing I suppose.

[tomfn]

Remember that you probably will have to rebind the reciever with trottle stick at the bottom after you have settup the esc. and callibrated the endpoints :-) I also had to callibrate 1 esc at the time with endpoints and without w tail mixer and gyro.

[MTBikerTim]

Originally Posted by tomfn

Remember that you probably will have to rebind the reciever with trottle stick at the bottom after you have settup the esc. and callibrated the endpoints :-) I also had to callibrate 1 esc at the time with endpoints and without w tail mixer and gyro.

Thanks tom I got that sorted now I have another issue. The throttle pulses when the gyro is plugged in, the gyro is working and the tail is locked in but every 2 seconds or so the throttle stops for a fraction of a second. I disconnected the gyro and used rudder direct to the mixer it works perfectly, just really hard to control the tail. I probably need to create a new thread for this I suppose. Bed time now though.

[tomfn]

The GWS V tail mixer opperates with 200Hz resolution, if the DS switch on the 401 is set to ON the gyro opperates with 270hz high speed pulses (this mode is for Futaba digital servos only). If your DS switch is set to ON, maybe this is your problem? What is your gain set at, maybe you have to lower the gain?

[MTBikerTim]

DS mode is switched off and my gain is switchable between 25% and 75%. If I understand the 401gyro correctly 25% should be rate mode and 75% should be HH. Those are the only 2 gains I have tried so far. I'll have to try a few more I suppose.

[MTBikerTim]

I borrowed a dodgy esky gyro and it solved the pulsing throttle problem but it wouldn't hold the tail. I think the pulsing problem was due to the funny signal the futaba gyro produces. One of my mates said JR servos behave in the same way when used with a futaba gyro. I'll have to grab a gy191 sometime.

[tomfn]

Glad to here that you sorted it out :-) I also think that it might be the pulses from the 401 that are not working togheter with the V tail mixer. The MKS 191 works great, other people also uses the Telebee gyro on their brushless Lama`s. They are both under 40,- USD.

[MTBikerTim]

Originally Posted by tomfn

Glad to here that you sorted it out :-) I also think that it might be the pulses from the 401 that are not working togheter with the V tail mixer. The MKS 191 works great, other people also uses the Telebee gyro on their brushless Lama`s. They are both under 40,- USD.

Yep you are probably correct. The futaba mixer may have worked but I never planned on using the 401 forever. I am also still lacking power. I still get absolutely no runtime out of a battery. Are those esky packs just complete rubbish?

[barak1001]

I had to set my throw for the throttle on my DX7 to 150% up and set the throw for the rudder to 150% left and right.

That allows the chopper to get full power.

I set the limits for both of the ESC using the throttle channel with the trim set at center.

[MTBikerTim]

Originally Posted by barak1001

I had to set my throw for the throttle on my DX7 to 150% up and set the throw for the rudder to 150% left and right.

That allows the chopper to get full power.

I set the limits for both of the ESC using the throttle channel with the trim set at center.

I'll have to give that a try. I have to get another gyro first though.

[barak1001]

Might want to try out either a Telebee GR201 or an MKS191.

Both have been proven to work really well in brushless Lama/CX2.

[MTBikerTim]

Originally Posted by barak1001

Might want to try out either a Telebee GR201 or an MKS191.

Both have been proven to work really well in brushless Lama/CX2.

Yep ordered the 191 today as well as an ar6100 to hopefully lighten the heli up enough so it will fly. If that doesn't help I suppose i'll go 3 cell.

[tomfn]

The MKS 191 will work great :-)

The AR6100 is 3,5gr. and the AR700 is 14gr. The 401 is 27gr. and the MKS191 is under 5gr. Your heli will be 33,5gr. lighter with the mks and the AR6100 :-)

The C10 motors should have more then enough power to lift the Lama. Even with the extra weight it should weigh around the same as the stock Lama (230gr with battery)?

Maybe you are not getting full trottle? Is your trottle travel adjustment set to -150/+150, is your trottle type in your esc. set to fixed trottle, the trottle endpoints must be callibrated with your esc(turn the radio on with full trottle, plug the battery into the heli and wait for several beps and then turn your trottle all the way down)? A 3cell 800mah battery will also ad around 20gr. of extra weight. Hope it works for you when the new parts arrive :-)

[MTBikerTim]

Originally Posted by tomfn

The MKS 191 will work great :-)

The AR6100 is 3,5gr. and the AR700 is 14gr. The 401 is 27gr. and the MKS191 is under 5gr. Your heli will be 33,5gr. lighter with the mks and the AR6100 :-)

The C10 motors should have more then enough power to lift the Lama. Even with the extra weight it should weigh around the same as the stock Lama (230gr with battery)?

Maybe you are not getting full trottle? Is your trottle travel adjustment set to -150/+150, is your trottle type in your esc. set to fixed trottle, the trottle endpoints must be callibrated with your esc(turn the radio on with full trottle, plug the battery into the heli and wait for several beps and then turn your trottle all the way down)? A 3cell 800mah battery will also ad around 20gr. of extra weight. Hope it works for you when the new parts arrive :-)

Thanks for the info Tom. Is that esc calibration info for the castle esc? I think the throttle end point issue is part of my problem. I haven't read anything about programming them other then it says that it is automatic.

Edit: Cool after reading through the stick programming instructions properly I now see that this probably calibrates the full throttle stick position, thanks tom. I'm an idiot. Sweet I'll give this all a go tonight and let you all know how it goes.

[barak1001]

I set my throttle endpoints on the ESCs with the throw set at 100% both directions, then I change it to 150% up on the throttle after it's set.

[MTBikerTim]

Originally Posted by barak1001

I set my throttle endpoints on the ESCs with the throw set at 100% both directions, then I change it to 150% up on the throttle after it's set.

I wonder how the mixer works. I assume the mixer is why you need to do this. I was having issues with mine still spinning the blades with the throttle at 0 which was a bit of pain. Calibrating properly will fix that though. Does the mixer slow one motor and spin the other faster to turn or does it just slow or speed up one motor?

[tomfn]

Hello again Tim.
The mixer slows down one motor and speeds up the other to turn the heli. The reason to set the trottle endpoints is to "learn" your esc the signal your radio gives at full and zero trottle. With the turnigy esc i had to sett the trottle to -150 to be able to callibrate it. I also had to do the settup with one esc. at a time and without the gyro. If you have the Castle link setting up the esc is realy easy.