Brushless Lama V4

[MTBikerTim]

Originally Posted by 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.

Yeah I'm a brushless car person so I know setting up end points is important for some reason I just didn't think it was needed with these escs. I ran through the setup via the radio one esc at a time (programed them with the castle link last time)) and it does seem to have helped a little bit with the power. I was having an issue with the gyro not working. Then I realised I was an idiot and you can't mount this gyro like the 401.

After that the new gyro works well. I get a bit of tail wag though. If I move the gain down to the point where the wag stops the tail drifts so I can live with a little wag.

My batteries must be shagged though. The runtime isn't very long (maybe 2 or 3 minutes) and the tail starts drifting towards the end as I'm almost at full throttle to keep it in the air.

The other little issue I was having was with the low throttle point. With the throttle off the blades would still spin. Not when I first plugged the battery in but after landing or crashing. So I enabled throttle hold on my transmitter and set that to -20% so low stick is 0% and throttle hold is lower. This seems to work well and it's good practice for crashing a bigger heli.

[barak1001]

I think that the issue with power is due to the mixer itself.

I think it's only putting out 50% of your stick when you push forward due to how it mixes both channels. I set the end points on my throttle ESC with my limits set to 75% high and 100% low yesterday and got way more power that way. I think I'm going to try the same thing with 50% high and 100% low and see if it improves things.

Just tried it outside, massive increase in power! I also set the rudder travel to 50% left and right and then set the endpoints on the rudder ESC that way. Then moved them back to 150% left and right.

As far as throttle hold goes, I have my gain plugged into my Aux channel and the light kit plugged into my Gear channel. So I use the flap switch to a change my gain. I have it programmed at 0%, 10% Up, and 20% up. When I first plug in the battery I have the switch at 0%. Then if I'm inside I flip to 10%, outside I switch to 20%. I also have the trim enabled for the flap channel so I can adjust the gain up or down on the fly if I need to.

Although this isn't as effective as throttle lock, I can flip the switch up and move the chopper around pretty much without the blades ever turning.

I chose not to fly in heli mode since it automatically robs you of your 5th channel if you do. I control the landing light of my light kit with my 5th channel.

[tomfn]

Tried setting the throttle endpoints with 50% limit today just to se and i don’t think i got any more power (rpm) with my set-up. When flying it seems to have more power but it is only because you get 100% throttle (rpm) at 75% stick movement. I do not have anything to measure the rpm but if i hold the heli the rpm will climb up to around 75% stick movement, from 75% up to 100% the rpm does not seem to climb.

After trying this i bind the receiver again with limits at -100/+100, then programed the endpoint in the esc again. If i hold the heli in my hand at full throttle and then increase the throttle limit from +100 up to +150 the rpm does not climb. If i lower the limit from +100 the rpm falls.

[barak1001]

What ESC are you using?

[tomfn]

I am using Turnigy Plush 6A.

[barak1001]

Strange, I'm using the same ESC.

I saw a marked improvement in head speed when I set the end points with the throw limited on the transmitter.

I'm using a DX7.

[MTBikerTim]

I should try increasing the upper end point on my radio then. I might see an improvement in head speed. My escs are definitely not at full power when I am at full stick. I will try moving my end point up and see how it goes.

I have also started getting more run time too. I must have just run the batteries longer then I thought at the start. I don't think i'm getting 10 minutes but at least over 5 now.

[barak1001]

I timed a flight tonight. 15:15 and I had 3.67 volts per cell (Probably should have set it down 30 seconds earlier, but I wanted to see if I could hit the 15 minute mark).

[MTBikerTim]

Bastard I'm not getting any where near that long. What batteries are you using?

I redid my electronics layout last night, shortened some wires and tidied it up a bit. I can now fit the body on and it looks good.

I changed the way the throttle hold works too like you said. I set the gain to 50% (really 0 gain) when on throttle hold and the blades do not spin at all when it's on.

I tried increasing the throttle end points to get more power and I do for a little bit then the power drops again. I think no matter what I do the power won't increase due to the automatic end point detection of the esc.

[barak1001]

Might be time to change out to el cheapo Turnigy 6amp ESC?

I'm flying generic batteries I bought off ebay.

Another thing to check is if your motor shafts are slipping. I finally got tired of screwing with mine and put blue thread clock on the set screw AND shaft.

Will be hell to ever get it out, but my rear motor shaft slipped constantly.

http://cgi.ebay.com/2-15C-11-1v-900m...3%3A1|294%3A50

$12.60 a piece, not too bad for 3s lipos. They will only last about 100 cycles, but they're cheap enough that you can buy 5 or 6 of them and fly constantly.

As far as weight goes, my chopper weights about 220 grams with light kit and all. I put all of my electronics forward rather than try and balance COG. You'd be amazed at how quickly my chopper can move in FFF.

[MTBikerTim]

Originally Posted by barak1001

Might be time to change out to el cheapo Turnigy 6amp ESC?

I'm flying generic batteries I bought off ebay.

Another thing to check is if your motor shafts are slipping. I finally got tired of screwing with mine and put blue thread clock on the set screw AND shaft.

Will be hell to ever get it out, but my rear motor shaft slipped constantly.

http://cgi.ebay.com/2-15C-11-1v-900m...3%3A1|294%3A50

$12.60 a piece, not too bad for 3s lipos. They will only last about 100 cycles, but they're cheap enough that you can buy 5 or 6 of them and fly constantly.

As far as weight goes, my chopper weights about 220 grams with light kit and all. I put all of my electronics forward rather than try and balance COG. You'd be amazed at how quickly my chopper can move in FFF.

Yeah I am starting to regret getting these speedies but like you have suggested I think I'll try a 3s pack first.

As far as CG goes mine is tail heavy due to the xtreme tail. Who makes a lighter tail similar to the xtreme. I also moved the linkages out on the servo arms for faster flight. It makes a bit of difference but not a huge amount. It makes the most difference when you first move the stick but then the top blades start to counter act the bottom and it slows down again.

I'll have to check to see if the motor shaft is slipping. Maybe that's why my tail drifts one way when I give it full throttle.

I noticed last night that one of the plastic gears would catch on the pinion at one point. I could not work out what it was catching but after forcing it a few times it seemed to go away. I'll have to investigate that a bit further too.

[barak1001]

Get a BoomTown model 4 boom.

It weights in at 2 grams less than the stock tail did. Great tail boom.

As far as the upper blades slowing you down, buy a Dynam Vortex flybar, then cut it down to 4.25 inches overall length, you'll be amazed at what your chopper will do after that.

[MTBikerTim]

Originally Posted by barak1001

Get a BoomTown model 4 boom.

It weights in at 2 grams less than the stock tail did. Great tail boom.

As far as the upper blades slowing you down, buy a Dynam Vortex flybar, then cut it down to 4.25 inches overall length, you'll be amazed at what your chopper will do after that.

I've got the vortex flybar. I'll move the weights in and see how it goes then.

That's the tail I was thinking of too thanks.

[tomfn]

Originally Posted by MTBikerTim

Bastard I'm not getting any where near that long. What batteries are you using?

I redid my electronics layout last night, shortened some wires and tidied it up a bit. I can now fit the body on and it looks good.

I changed the way the throttle hold works too like you said. I set the gain to 50% (really 0 gain) when on throttle hold and the blades do not spin at all when it's on.

I tried increasing the throttle end points to get more power and I do for a little bit then the power drops again. I think no matter what I do the power won't increase due to the automatic end point detection of the esc.

Do you have the possibility in the castle link to set the throttle to fixed endpoints? If so i would have tried that and programmed the endpoints one more time.

[MTBikerTim]

Originally Posted by tomfn

Do you have the possibility in the castle link to set the throttle to fixed endpoints? If so i would have tried that and programmed the endpoints one more time.

Yeah I found a cheap 3 cell and bought it, will probably get here tomorrow. It's not going to help though. I discovered tonight what is probably causing all my problems, the upper gear is stripped. I am amazed the thing flew at all. The pinion didn't even touch the gear at one spot. So that is what the catching was that I described in a previous post too.

Anyway that problem is easy to fix. I do have a question though. How to you mount the 3s pack with the v4 battery holder?

[barak1001]

A piece of plastic and some cheap velcro strips from Walmart.

[Kevo450]

Anyone know if the vtail mix function coudl be used to remove the need for an onboard vtail mixer ??

I know that both the dx6 and dx7 have that feature.

Thinking about doing this to a cx2 I have laying around with burnt motors

[dragonue]

In regards to a Lama V4 Brushless Upgrade, I have just successfully completed a double brushless conversion using the Turbo Ace Brushless Conversion Kit from http://wowhobbies.com/brushlessupgra...skylama34.aspx (Thanks Jonanthan for making this conversion so easy). The instructions, the connectors, the mounting holes and the pre-installed pinions were all well-thought-out and most importantly my Brushless Lama V4 worked on the first try (although some minor adjustments also helped later) and the extra torque, lift, manuverbility, excellent tail hold and flight time were simply an amazing combination. All in all it only took me 20 minutes.

[Jack the R]

Originally Posted by MTBikerTim

Yeah I found a cheap 3 cell and bought it, will probably get here tomorrow. It's not going to help though. I discovered tonight what is probably causing all my problems, the upper gear is stripped. I am amazed the thing flew at all. The pinion didn't even touch the gear at one spot. So that is what the catching was that I described in a previous post too.

Anyway that problem is easy to fix.

I've been through 3 outer shaft gears on my v3. I've now got in on an Xtreme outer shaft with replaceable outer shaft gear. If you get this problem figured out, be sure to post your solution. I'm getting tired of replacing stripped gears.

[Mr.Andersen]

I was sitting down and playing a litle around with my DX6i radio.
The original 4 in 1 box use 1 rotor to controll rudder and gyro function and that would be weary easy to replicate on the DX6i radio together with a spectrum RX, brushless motors, ESCs and one gyro.
Set throttle curve and pich curve linear and set swash type to 90 degree.
If watching the monitor now throttle and aux indicator will move paralell but oposite so reverse the aux channel.
Now they bought will work in paralell.
Now use throttle and pitch channal fore the two ESCs and mix in rudder to pitch so the ESC controlled bye the pitch channal will allso be set off bye the rudderimputs.
A gyro on the same channel controlling the ESC will then stabilise the tail and controll it like a electric tailrotor on a single rotor heli with separat tail motor.
I even think it would be flyable without any gyro but the tail will allways drift a litle like the tail of a stock lama doing allready.

But are there no motors from hobbycity possible to use on a Lama?