Single Servo Flaps and Upgrading a Super Cub Questions

[Jimd0586]

Hey all, I've got a super cub and I love it. A buddy bought a Flyzone Beaver, and it has scared the hell out of me to fly... just too powerful. I landed it successfully on the lake, but it's just too much plane for me. Instead, I opted to upgrade my Super Cub to learn 4 and 5 channel flight before moving to something bigger.

I added 8 inch ailerons but didn't remove the dihedral. Consequently, my roll ability is minimal... I'm thinking of taking out the dihedral and making the ailerons 10 inches. Either way, the two servos and the hardware currently in the wings really add on weight and seem to bog down the Cub... I would like to add flaps with just one servo and was wondering if anyone had any suggestions and pictures.

I am also considering changing out the engine and ESC to power this sucker... again I am looking to change this from a 3 channel trainer into a more powerful 5 channel trainer before I move onto the Beaver. If I wreck the cub I wouldn't feel nearly as bad.

Anyone know a solid brushless motor, motor mount, ESC, and Prop combination that is not outrageously expensive... and if a 1300 MAH battery would still give me decent flight time (around 8-10 minutes)?

I know this is pretty particular, but this is a thread for builds...

Any help would be great. Oh, and I also already have a 6 channel receiver and DX6i.

Jim

 

[DDSFlyer]

There's a great thread on rcgroups that you can use for reference, but with my super cub I have only upgraded the power system and never went to ailerons and such. David did an upgrade on the FT channel a while back.
What I did was go to a Park 480 motor and 30 amp red brick ESC. I also got a custom motor mount to mount it to the stock firewall. I also replaced the Rx with an Orange Rx 615 and did the vertical battery mod to fit a 2200mAh battery. I flew it recently after not flying it for awhile and it still is a blast to fly. It is WAY overpowered, but will carry a gopro in the heavy housing no problem. It seems to fly forever on 2200mAh so I never worry about it. Have fun and flatten that wing with a carbon fiber spar, you already have the ailerons anyways

 

[Foam Addict]

Hey all, I've got a super cub and I love it. A buddy bought a Flyzone Beaver, and it has scared the hell out of me to fly... just too powerful. I landed it successfully on the lake, but it's just too much plane for me. Instead, I opted to upgrade my Super Cub to learn 4 and 5 channel flight before moving to something bigger.

I added 8 inch ailerons but didn't remove the dihedral. Consequently, my roll ability is minimal... I'm thinking of taking out the dihedral and making the ailerons 10 inches. Either way, the two servos and the hardware currently in the wings really add on weight and seem to bog down the Cub... I would like to add flaps with just one servo and was wondering if anyone had any suggestions and pictures.

I am also considering changing out the engine and ESC to power this sucker... again I am looking to change this from a 3 channel trainer into a more powerful 5 channel trainer before I move onto the Beaver. If I wreck the cub I wouldn't feel nearly as bad.

Anyone know a solid brushless motor, motor mount, ESC, and Prop combination that is not outrageously expensive... and if a 1300 MAH battery would still give me decent flight time (around 8-10 minutes)?

I know this is pretty particular, but this is a thread for builds...

Any help would be great. Oh, and I also already have a 6 channel receiver and DX6i.

Jim

Hey Jim!

I have had 2 SCs, an LP and the original SC.

I am a weird character who still uses brushed motors if they are given to me, but that means I know a few tricks.


EDIT: this combo draws only 11-12 amps at WOT, so you can still use your stock lipo.

Do you already have the LP? If so, just get a brushed ESC (20 amp) from hobbyking, an orange RX receiver, and a GWS 11x7 HD prop.

Replace the stock RX/ESC brick and prop then enjoy!

This combo has 15-20 min flight times when throttled back, but can can prop hang at 6000'. It also drags itself off the water very nicely.

A bit of advice, if you go brushless, I would recommend either a low KV park 450 or a DT-750. With a 35-36-1000 I discovered that the SC has a nasty snap roll at high speeds regardless of wing reinforcement.:black_eyed:

 

[Jimd0586]

Thanks guys!

I actually had a bad crash with my first SC months back... it was an LP. I thought the damage was so bad that I bought a new SC S version. Flew it, improved my flying, and subsequently went back and repaired my LP. I got her flying. Can't say the damage didn't change her, but she is airborne. As such, I have two SC's! So if one mod fails, I can still use the old one for conventional flights.

 

[Foam Addict]

I'm glad you fixed it! No problem, we're glad to help.

Either way, it's a great plane, even with a little "crash character".:black_eyed:

Hey, would you be willing to tell me how many channels the safe RX brick has? I thought it was three, but I can't find that anywhere.

 

[Jimd0586]

The safe flight Super cub? The newest one? 3. I know for a fact because I only brought it to the cabin this weekend with both the stock wing and the aileron wing. I left the LP at home. I decided to fly the cub with ailerons and realized that the receiver didn't have a 4th port. The 4th port on it is a bind port. Needless to say, I didn't get to fly with ailerons over the weekend.

 

[Foam Addict]

I figured they'd do that.

Thank you!

 

[joshuabardwell]

Here's a good example of how to do flaps with one servo. Although, frankly, with the additional weight of the hardware, I'm not sure you wouldn't be better off just putting a second servo in.

https://www.youtube.com/watch?v=f8l_fzUYXMY

 

[Jimd0586]

I went with the Park 450, 30 Amp ESC, and a customrc motor mount... though I may have gotten the 1050kv instead of the 890. Will that create all kinds of problems?

Also, what prop is the best match? I fly with floats a ton. Although the shaft is different, pretending the stock engine and the Park450's were identical and could use the stock 9x6 or 10x8 props, would the park450 have higher performance... or must you match a different prop with the engine to see results?

Thanks.

 

[Foam Addict]

I went with the Park 450, 30 Amp ESC, and a customrc motor mount... though I may have gotten the 1050kv instead of the 890. Will that create all kinds of problems?

Also, what prop is the best match? I fly with floats a ton. Although the shaft is different, pretending the stock engine and the Park450's were identical and could use the stock 9x6 or 10x8 props, would the park450 have higher performance... or must you match a different prop with the engine to see results?

Thanks.

Well, good for you!

If you got the 1050 KV variant, I'd recommend an APC 10x3.8- 10x5, or possibly even a GWS 10x6 HD prop.
The stock props are awful IMO.

If you got the 890 KV variant then I'd recommend the GWS 11x7 HD. Absolutely my go to prop for sub 1000 KV motors.

Have fun!

 

[Jimd0586]

Ok. So can anyone explain to me why the upgrades from the stock brushed motor to a brushless 450 or 480 sees such a big performance increase? I am trying to understand KV and prop pitch and diameter (top end speed and acceleration)... its just that the stock cub turns a 9x6 or the 10x8 for the floats on the stock brushed engine... yet, people upgrade the engine to brushless and seem to have relatively similar prop sizes, yet report huge performance gains... is the brushed just a really low KV rating... like 600 or something? I'm just curious why the big gains with the newer engine over the stock...

 

[Craftydan]

After the gear box, typically yes.

Keep in mind, most brushless motors are direct drive, becasue they're designed to spin quite a bit slower with a LOT more torque.

 

[Foam Addict]

Ok. So can anyone explain to me why the upgrades from the stock brushed motor to a brushless 450 or 480 sees such a big performance increase? I am trying to understand KV and prop pitch and diameter (top end speed and acceleration)... its just that the stock cub turns a 9x6 or the 10x8 for the floats on the stock brushed engine... yet, people upgrade the engine to brushless and seem to have relatively similar prop sizes, yet report huge performance gains... is the brushed just a really low KV rating... like 600 or something? I'm just curious why the big gains with the newer engine over the stock...

The reason is that Brushed motors are typically 10-15% less efficient and are around 3 times the weight for the same current draw.

The idea for any power setup is to put the prop and motor in their optimal efficiency range. For brushless motors, that can be anywhere, but cheap brushed motors are highly efficient at >25000 RPM, while props are generally more efficient at lower RPMs. That stock motor is a speed 480, it's geared 3:1 for 750kv and good for about 14-16 amps.

My best flying plane uses a custom wound 400kv motor spinning a 12x8 prop at around 4000 RPM, the motor only draws 3-4 amps static, yet gives a 16 oz plane pretty incredible vertical performance and 15-30 min flight times.

So the answer, in a nut shell: brushless motors are more efficient and much lighter, giving a far better power to weight ratio, but gains can also come by using a prop more efficiently.

 

[Americium95]

As far as single servo flaps go, I was scrolling through Hobbyking's website the other day and found this:
It was one a Cessna 182 foam model.

 

[Jimd0586]

Thanks everyone for the help. I experimented a bit with a one servo setup and found it too tricky to make. I decided to use a two servo setup instead, and it seems to work just fine. I am now trying to trim my flaps on my DX6i.

My SC now has a Turnigy Park450 installed on a customrc motor mount, a 30 AMP ESC with UBEC, a six channel spektrum receiver, flaps, ailerons, floats with one single float rudder installed, and an APC 10x7 prop. Have not flown it yet. Not sure when it will happen.