Help! Simple Cub Takeoff/Power Problem

[AIRFORGE]

Yep. My fingers are in the right spot. I have a few glue drops over them so I can find them easily. And my prop was facing the right direction. That's the first thing i checked, so I know the direction isn't a problem.

Your fingers are too far forward of the actual CG marks on the plans. The CG should be on the lead edge of the wing spar. In the video, it appears to be balanced overly nose heavy, judging by the position of your finger tips, which are near the lead edge of the wing, not the spar. Try correcting the CG marks to the lead edge of the spar, and balance slightly nose heavy.

 

[Crutchy]

@Addicted I put glue where the holes are on the Speed Build Kits. That's where the CG is at. Unless FT is wrong. And my fingers aren't straight up. They are slightly angled back, so the tips tips my fingers are slightly in front of the leading edge of the spar.
@Matthewdupreez Do you know where I can get APC 10×4.5 props?
@The Hangar Thanks for letting me know!

 

[Matthewdupreez]

https://www.horizonhobby.com/product/multi-rotor-propeller-10-x-4.5/APC10045MR.html

https://www.apcprop.com/?s=10x4.5

 

[Hvon11]

Check that throttle high point is calibrated on ESC. You may not be developing enough thrust. Normaly you can set ESC throttle high point by putting throttle all the way up before powering on plane. Power on plane and listen for some beeps and then lower throttle all the way within two seconds. Check your ESC instructions for proper procedure.

 

[Crutchy]

https://www.horizonhobby.com/product/multi-rotor-propeller-10-x-4.5/APC10045MR.html

https://www.apcprop.com/?s=10x4.5

These propellers are for multi-rotor aircrafts. Is that going to mess anything up?

 

[Crutchy]

Check that throttle high point is calibrated on ESC. You may not be developing enough thrust. Normaly you can set ESC throttle high point by putting throttle all the way up before powering on plane. Power on plane and listen for some beeps and then lower throttle all the way within two seconds. Check your ESC instructions for proper procedure.

My transmitter is a FlySky FS-I6X, and it won't turn on without the throttle being all the way down. Not sure if I'll be able to do that.

 

[The Hangar]

My transmitter is a FlySky FS-I6X, and it won't turn on without the throttle being all the way down. Not sure if I'll be able to do that.

You can put the throttle to full after turning the transmitter on, then turning on the plane. Just take off your propeller first in case anything wonky happens.

 

[Crutchy]

You can put the throttle to full after turning the transmitter on, then turning on the plane. Just take off your propeller first in case anything wonky happens.

Okay! I'll look and see what ESC I have and look at how to calibrate it!

 

[Matthewdupreez]

These propellers are for multi-rotor aircrafts. Is that going to mess anything up?

Should be fine...

 

[Crutchy]

Okay, I calibrated my ECS, and I don't know if this is an issue that I had before and I just didn't notice it, or what, but at about 60% throttle, the motor starts to change its noise and starts to sound like it's vibrating more, and then at 75%, the throttle won't go any higher. I calibrated it all correctly, and it did this. Not sure why.

 

[Matthewdupreez]

Okay, I calibrated my ECS, and I don't know if this is an issue that I had before and I just didn't notice it, or what, but at about 60% throttle, the motor starts to change its noise and starts to sound like it's vibrating more, and then at 75%, the throttle won't go any higher. I calibrated it all correctly, and it did this. Not sure why.

Check that the motor mount screws are not, going to far in and pushing against the windings....

 

[Crutchy]

You mean into the firewall?

 

[Matthewdupreez]

You mean into the firewall?

No..the ones that attach the x bracket onto the motor

 

[Crutchy]

As far as I can see, everything is okay with the screws and the motor. I'm so confused with whats happening to my motor and why it's making that noise and doing what it's doing, and I'm confused why it won't takeoff.

 

[Matthewdupreez]

As far as I can see, everything is okay with the screws and the motor. I'm so confused with whats happening to my motor and why it's making that noise and doing what it's doing, and I'm confused why it won't takeoff.

A video of the motor acting up?

 

[Hvon11]

It sounds like a mechanical restriction on the motor which is almost always too long of a screw on the X bracket as indicated by Matthewduprez. Or it is a problem with the propeller out of balance or slipping on shaft. Or a loose motor bullet connector.

1) Remove propeller and check that there is the proper bushing to snuggly fit your motor shaft. If correct then return propeller and tighten prop nut snuggly so that prop can’t turn when you hold the body of the motor and try to turn prop. Power on and see if noise/vibration is gone.

2) This will be a hassle but if you haven’t done it, it needs to be done. Remove the propeller and remove the motor from the firewall. Now remove the motor screws attaching the X bracket and remove X bracket. Push each screw into a hole in the X bracket and see how far they pass through. There should be no more than 1/8” of exposed threads. That is, just enough threads are exposed to mate with the thickness of the threaded hole on the motor. If too long of a screw was used and pushed into the motor windings, the motor may be ruined.

3) Pull each motor bullet from the ESC and reconnect firmly. Brushless motors can act weird if one of three connectors is loose.

4) Reattach X bracket and power up transmitter and plane. Holding the X braxket in your hand, run the throttle up and see if it is smooth and gives linear control form 0 to 100%

5) Reassemble power pod and return to plane. Attach propeller and test again.

Good luck.

 

[Crutchy]

Thank you! I will try this! Also, I have a 10×60 Propeller, and I was wondering if it would work. I had it from a few years ago and forgot I had it.

 

[Hvon11]

A 10X6 will be too much prop for the recommended power pack B motor which is a 2212-1050kv. I run a 9x4.5 on my Piper Cub but have used a 9x6 previously. the 9x4.5 is more responsive to throttle in my experience but both will work.

If you are running a power pack C motor, the 2218-1180kv, then a 10x4.5 up to a 10x6 will work fine.

 

[Crutchy]

Oh! Well maybe I should just get the C Pack instead. Will that solve my issues completely?

 

[Hvon11]

The B pack motor is well suited for the Cub with a 3S battery that weighs about 150grams. I hesitate to recommend an Amp-Hour size because two different brands with the same Amp--hour rating can have significantly different weights. You can get a Tattu 1800mah that weighs 156g that will work fine but there are many 150g batteries with larger Amp-hours but are a bit spendy.