Blade CP upgraded, now tail wont hold

[bohh]

Hey guys,

I upgraded my old Blade CP (not the pro) to a 3600kv brushless motor with 8t pinion, and put a DD GWS EHS50 motor with a 4025 sqaure prop on the tail. I then swapped the whole thing over to my JR 6102 radio. I have no revo mixxing set and I have the tail set up as a tractor, to blow air over the tail motor. And I did it in a way so that I could use the stock 4-in-1 gyro and esc for the tail. (took some stuff out and did a few mods to the 4-in-1 to do that)

So what's my issue? Well, I go out to try it out and I find that it's nosing hard left soon as it gets light on the skids. No prob, tweak the proportional a little - try again. Same thing. Long stoy short I've ended up with full proportional and full gain and it still noses left as soon as it's light. I have to end up giving it almost full right rudder stick to get it to hold straight.

Any ideas what the issue is?

Thanks,

-Mike

[HeliDan]

Did you reinitialize (unplug then re-plug) the battery after each adjustment?

[bohh]

Yep, made sure to do that for both the gain and proportional adjustments (I think I read it was only need for proportional though)

[zooland1]

Check you tail rotor orientation. It sounds like your gyro is continually correcting in the reverse input or not working at all. My Trex did this when the gyro reversed orientation on me. The tail was working properly with stick input, but would spin out of control as soon as I lifted off. You could try flipping the plug for the motor and if everything is backwards then reverse channel 4 on the radio. You might also try the stock Rx temporarily with the stock Tx and that way you will be able to tell if it's in the radio or tail.

[bohh]

Thanks zooland. I will give that a try, but I'm pretty sure it's setup right. I mean if the gyro was correcting the wrong way it would spin to the left at a fast rate right? It seems what happens is I'm tail in, get it off the groun and it turns 90 degrees to right side in and stops.

[rcboosted]

Are you still using the stock 4in1 as the receiver or are you using a seperate receiver? If you are, how are you using the 4in1 as a gyro for the seperate receiver?

[Funky]

I know it doesn't sound right, but have you tried a smaller prop? 4025 square is a big prop and might not be getting enough speed to compensate for the main motor's torque. I use a 3020 square prop for my direct drive and it works great. The light weight lets it build a lot of speed to compensate for a brushless main motor (I am running brushless 370 4100 kv). It also slows quickly for left turns or quick dives. The smaller prop also helps the motor run cooler. I tried the 40-something prop (not sqaure) but it didn't hold the tail as well as the 3020 and my tail motor was running very hot.

[carlo_the_wonder_frog]

Are you using the stock transmitter? You will probably have to set your trim differently to compensate for the Yaw. Normally this issue could be taken out with subtrim on the rudder channel, but the stock Tx doesn't support that feature.

If the Gyro was reversed, the heli would spin uncontrollably no matter what input you give, so sounds like its correct the way it is.

[bohh]

HI guys,

Tried some of the suggestions you've all given. Tried a smaller prop and even a bigger prop and no luck. I'm also using a JR6102 radio. Set rudder trims full right (and now the tail spins all the time) and still no luck. Thinking that mabye the tail can't compensate the torque of the rotor.. (though other people are using the same setup) I reduced my throttle curve to 50 at the highest point. Not enough lift to fly, but even at this point full right stick does not make the nose go right.

I've also changed the orientation, no luck. I've also plugged the motor in backwards (switched the polrity to make sure it didn't hace anything wrong) and it made it worse as you'd expect.

I'm using a JR RX, a brushless esc for the main, and the stock 4-in-1 esc and gyro for the tail.

rcboosted: I opened the 4-in-1 and took out the RX board so all I was left with in the box was the 2 esc's and the gyro on the remaining board. I just plugged my tail motor into the 4-in-1 like usual and used some servo extensions to go from the ports that the RX usually goes in to go to my new RX. But you have to create a "Y" and plug the other port in to the main throttle too. It seems the 4-in-1 needs to see something on the main motor or it won't work either. Though - as you can see I'm having issues so mabye my work around doesn't work. I guess if we can't figure this out the next step would be to try a seperate gyro and esc for the tail and see how that works out.

[chopperdudes]

so if i get it correct, it'll spin on the ground when it's skids are light, but will hold during the flight, right? if that's the case, i'm 200% sure it's your revo. even if you didn't do anything to it, the stock tx has revo mixed in it, play with the low end of your revo, i have a futaba 7c and when i set the low end revo right (suddenly chop throttle and tail will hold), it'll swing on the ground, but i can correct it with rudder imputs.

[bohh]

Negative. It will spin on the floor when its light on the skids, and full opposite rudder will not make the nose hold in the least. Still spins. Get it in the air, same thing, spins and full rudder does nothing. Of course I don't keep it in the air more than a few seconds but that's whats happening until I put it down.

[carlo_the_wonder_frog]

Is the prop on correctly? the gws and prop size letters should be viewable from the front of the prop. I doubt thas it, but worth a shot. What side is the motor on? It should be on the right side of the boom as you look at the tail with the Prop on the left side. You have probably already verified all this and are just pulling your hair out trying to figure it out. Good luck and if you do resolve the issue make sure to let us know.

[bohh]

Thanks for the continued support, but yup - everything you outlined is correct. I'll let you know if I get somewhere though. :arggg:

[chopperdudes]

if your porpotional is all the way clockwise, and i know this may sound stupid, but you may want to try another tail motor... maybe you just got a defective one. also,
It seems what happens is I'm tail in, get it off the groun and it turns 90 degrees to right side in and stops
i'd strongly suggest you try to max out your low end revo point (try both positive and negative) to see if i make a difference. also, you might want to see if someone can lend you a 3 in 1, it's not likely, but you may have damaged your 4 in 1 during soldering.