jstrach

So I finished up my ElectriCub and used the T600-R motor / transmission assembly as instructed. This configuration supposedly is the best performance setup per the manufacturer. It's utilizing an 8.4v 3600mAh NiMH for power running the ElectriFly C-35 Mini ESC with a Master Airscrew 10x8 GF Nylon propeller. All recommended by Great Planes.

Anyway, the plane is completely underpowered. It won't even get down the runway at adequate takeoff speed. I'm terrified if it did get into the air it would be so underpowered it would stall immediately. Which would be catastrophic to my delicate nature because this kit went together very, very well. I'm so proud of her. She looks great and I really want to fly her.

SO..... what other motor / battery configuration would someone recommend? Has anyone modified their ElectriCub for this very reason and if so, what did you do?

FYI: ElectriCub Weight: 3.3 lbs

Please and thank you!!! (in advance)

Dr Kiwi

A monstrously heavy, gutless 600 on 7-cells is a recipe for disaster.....you probably want a brushless motor, running on 3s or 4s Lipo, which can cope with 450W (~150W/lb). This Dualsky might do well. http://2dogrc.com/product/dualsky-xm...-350w-21-speed. A Cub doesn't need massive power so this motor spinning a 10x8 might well be ideal.... you won't be needing WOT!

Motor: Dualsky XM3542CA-5; 1120rpm/V; 2.11A no-load; 0.027 Ohms.
Battery: Thunder Power TP2650 (G4 ProPower 45C) (45C); 3 cells; 2650mAh @ 3.7V; 0.003 Ohms/cell.
Speed Control: Castle Creations Phoenix 45; 0.0026 Ohms; High rate.
Drive System: Direct; 10x8 (Pconst=1.17; Tconst=1) direct drive.
Airframe: Anything you want.

Motor Amps = 40.7
Motor Volts = 10.6
Input (W) = 432.2
Prop RPM = 9952
Thrust (oz) = 51.0
PSpd (mph) = 75.4

You probably don't need anywhere near that pitch speed so a 10x5 APC E might be better, if you want to be conservative (or an 11x5.5 APC E if you want more thrust)

jstrach

Dr.Kiwi - you simply rock! I will begin investigating immediately.

Icontacted 2DOGRC and Iam asking those guys if they have a more economical ESCImight use. They're at a show in Toledo and will respond on Monday(tomorrow).

jbogdano

My Feedback: (13)

Probably a bit late for you but . . . I had a nearly identical setup and it flew reasonably well. My battery was the 3000 mah great planes nimh. My battery weighed a few oz less than yours but the same power output. I also used an APC "thin electric" prop, 10x8 if I remember correctly. It was no 3D ship for sure, but it could lumber around the pattern with the occassional loop and roll.

I think you could get your setup to work without too much hassle by just changing the propeller and battery out. Good luck and let us know how it went!

Jeff

jstrach

It's not too late. I haven't done anything with my Piper Cub yet. It is just sitting. I am skeptical that just changing out the battery and prop will do anything. (I believe I'm already running a 10x8 Electric prop). I still feel the motor needs to be a direct drive and not through the transmission. Just not sure which motor to get... and then the ESC is still an issue.

flytreetimes

I flew m yElectra Cub on 185 watts with no problems at all. I used a 2836 1000 with a 10/6 prop (Apc) 2200/3S 20C Flightmax battery. Overpowering this plane will get you into trouble almost a soon as underpowered. The original 600 brushed did not have enough oomph even on a 3cell lipo to get this little bird airborne. The plane flew very scale on this little motor (2836-1000), could just pull an eggshaped loop.
My AUW with this system was 2 lbs,4ozs.
A turnigy 3536-1000 would provide 250- watts or so for little more spirited performance on the same 2200/3S battery Fwiw

blvdbuzzard

I built one way back when and used a 8 cell sub "C" pack, direct drive 8X4 prop. Flew for about 3 minutes before running low on power. After a while I pulled the electric out and put in a Magnum .10 sized glow engine. Flew it for years with that setup.


Now I have the plans and will be scratch building a new one. I do not want glow this time so I figured I would make a better brushless/lipo setup. Here is the setup I am going to use in my ElectriCub.

http://www.hobbypartz.com/volcano-40...oller-esc.html

http://www.hobbypartz.com/96m601-big...20-1100kv.html

http://www.hobbypartz.com/83p-2200mah-3s1p-111-20c.html

This setup running a 11X7 prop should give around 60 ounces of thrust. So if your Cub weighs in at 3.3 pounds that is 52 ounces, this setup should be right there for you.


Buzz.

jstrach

FOLKS

To follow-up on this thread, I now realize I'm most likely suffering from a high altitude problem regarding my ElectriCub being underpowered.  I'm most likely going to convert to a direct drive - lose the transmission - and be more aggressive with my prop to compensate for the 6000 ft altitude....

Thanks.
Jerome

blvdbuzzard

Are you still using the NIMH batteries? If you would use a brushless motor, ESC and a new LIPO battery, all of that together would weigh less the just the battery pack. It would save a pound at least. That would really help the power to weight issue plus give you a lot longer flight times.

https://www.leaderhobby.com/product....=9394001223744 (4.3 ounces)

https://www.leaderhobby.com/list.asp...&categories=64 (6.8 ounces)

https://www.leaderhobby.com/product....=9394001224050 (2 ounces)


Let us know how it works with a direct drive and different props.


Buzz.