Help! My first question: Can I Fly "Carbon Cub S+" with 2200 mAh 4S Battery

[Yoshio]

Hi there,

happy to be here and hoping to receive some good advice since I am not a battery expert.

-> I have the "Carbon Cub S+ (RTF)" which came with the recommended 1300 mAh 3S battery. I know that many people are flying it also with a "2200 3S" pack and this is also listed in the manual as an option. Now, I l also have a "2200 4S" battery for another plane (V900). Can I use it also with the Carbon Cub S+ resp. what do I need to consider?

Thanks a lot!

 

[FDS]

The huge extra weight of a large 4s. It will mess with the CG. You would want a 4s battery the same weight as the 2200mah 3s not just the same capacity, usually they are lower, like about 1500mah capacity, to account for the extra cell.
It will easily have the power to haul ass with that in, it’s just wether or not you can balance it. Also check that the electronics, especially the ESC, can take 4s.

 

[heartland]

I wouldn't. The motor and ESC are only designed for 3S.
I actually fly mine with the 3S 1300 most of the time. Seems to fly best with the lighter battery.

 

[Yoshio]

The huge extra weight of a large 4s. It will mess with the CG. You would want a 4s battery the same weight as the 2200mah 3s not just the same capacity, usually they are lower, like about 1500mah capacity, to account for the extra cell.
It will easily have the power to haul ass with that in, it’s just wether or not you can balance it. Also check that the electronics, especially the ESC, can take 4s.

Thanks a lot FDS for your answer. Actually size and weight of 2200 3S and 4S only slightly differ and that is in my opinion mainly because my 3s is a Modster and the 4S is a Spektrum Smart Battery, which are in general a little bigger than other batteries with the same specs due to the microchip and packaging. But maybe you are right and even that difference crosses the line.

 

[Yoshio]

I wouldn't. The motor and ESC are only designed for 3S.
I actually fly mine with the 3S 1300 most of the time. Seems to fly best with the lighter battery.

Thanks a lot heartland! I guess I will follow your advise to not risk any (more) damage caused by battery issues. I had a decent crash yesterday ... battery wasn't fixed well and when ascending fast and steep in expert mode the EC3 connectors lost connection as the battery rushed to the back of the compartment. Plane went down INTO earth - even steeper and faster. Repair time

 

[heartland]

Yoshio, I hope you can fix it. It's a great flying airplane.
I like my 3S 1300 battery quite a bit forward and I use a velcro strap to capture and secure it.
Also, I get 8 to 10 minutes flight time with the 1300 with moderate to full speeds.
Enjoy!

 

[cranialrectosis]

4S will spin your motor much faster than 3S. If you want 4S power, you will need to check to see if your ESC and motor will handle the current. Most people prop down when going up a cell. If you were running a 10" prop on 3S, try a 9" prop on 4S.

Experimenting with lipos and power levels is what gave us racing quads. In 2012 most of us were on 3S. It was @FinalGlideAus who moved us into 4S both here on FT forums and internationally circa 2014. We all thought he was nuts. He was right and now we see 5S and even 6S racing quads.

More voltage spins props faster. You get a LOT of power going from a 6" prop on 3S to a 5" prop on 4S. It is a VERY noticeable bump in thrust.

Less voltage spins props slower. You get less thrust going from a 9" prop on 4S to a 10" prop on 3S. But you are more efficient. If both lipos are 1300mAh you CAN (depending on how you fly) get more flight time from the 3S particularly if the 3S is lighter.

My big suggestion... When you do experiment with power, don't do it on your ONLY flyer.

One last note. A heavier 2200mAh lipo MAY get you more flight time. But it weighs more. A heavier plane flies more sluggishly in the air. It takes more experience and more planning to fly a heavy plane than a light one. You may crash more often with the heavier plane and since the plane is heavier, it WILL take more damage in a crash.

Learn as light as possible. It will save you repair time.

 

[Yoshio]

4S will spin your motor much faster than 3S. If you want 4S power, you will need to check to see if your ESC and motor will handle the current. Most people prop down when going up a cell. If you were running a 10" prop on 3S, try a 9" prop on 4S.

Experimenting with lipos and power levels is what gave us racing quads. In 2012 most of us were on 3S. It was @FinalGlideAus who moved us into 4S both here on FT forums and internationally circa 2014. We all thought he was nuts. He was right and now we see 5S and even 6S racing quads.

More voltage spins props faster. You get a LOT of power going from a 6" prop on 3S to a 5" prop on 4S. It is a VERY noticeable bump in thrust.

Less voltage spins props slower. You get less thrust going from a 9" prop on 4S to a 10" prop on 3S. But you are more efficient. If both lipos are 1300mAh you CAN (depending on how you fly) get more flight time from the 3S particularly if the 3S is lighter.

My big suggestion... When you do experiment with power, don't do it on your ONLY flyer.

One last note. A heavier 2200mAh lipo MAY get you more flight time. But it weighs more. A heavier plane flies more sluggishly in the air. It takes more experience and more planning to fly a heavy plane than a light one. You may crash more often with the heavier plane and since the plane is heavier, it WILL take more damage in a crash.

Learn as light as possible. It will save you repair time.

WOW, that's a ton of great advice.

Yoshio, I hope you can fix it. It's a great flying airplane.
I like my 3S 1300 battery quite a bit forward and I use a velcro strap to capture and secure it.
Also, I get 8 to 10 minutes flight time with the 1300 with moderate to full speeds.
Enjoy!

Yeah, thankfully I ordered the S+ with three 1300 3S. Ordered some (hopefully) strong hook tape yesterday to fix the battery better. Thanks for the tip though!

ANY IDEA how to strenghten the EC3 connectors in a way that changing batteries will still be convenient? Just in case anything goes wrong again with the battery fixation.

 

[heartland]

Yoshio, I'm a little surprised the EC3 connector came loose. I have been using them for a long time and mine seem very tight to me, takes a little side wiggling to get them loose. Make sure you have them pushed all the way together. I coil the connectors and the wires in front of my battery in the bay in a way that should keep them connected. Do all 3 batteries seem loose? If so, maybe the ESC end is the problem. Or is it just 1 of the batteries? Try to isolate the problem.

 

[cranialrectosis]

Ordered some (hopefully) strong hook tape yesterday to fix the battery better

I used to use hook tape on the lipo and hook tape on the plane and stick them together. Doesn't work well enough IMO.

Now I put hook tape on the lipo and use a hook tape strap, or two if I can fit them, to lash the lipo down tightly to the airframe. This way there is no stress on the connector, ever.

 

[heartland]

Yoshio, use this in addition to the tape:

https://www.horizonhobby.com/hook-and-loop-fastening-strap:-20x280mm-spma4020

 

[Yoshio]

Yoshio, use this in addition to the tape:

https://www.horizonhobby.com/hook-and-loop-fastening-strap:-20x280mm-spma4020

Heartland you are so helpful, thanks. I opened my laptop right after I pulled this epic failure out of the plane to search for another solution and got the answer right away. Very cool!

 

[Yoshio]

Yoshio, I'm a little surprised the EC3 connector came loose. I have been using them for a long time and mine seem very tight to me, takes a little side wiggling to get them loose. Make sure you have them pushed all the way together. I coil the connectors and the wires in front of my battery in the bay in a way that should keep them connected. Do all 3 batteries seem loose? If so, maybe the ESC end is the problem. Or is it just 1 of the batteries? Try to isolate the problem.

Again your were right: I hadn't pushed them all the way together. Also the wiggling-tip to disconnect helped.