Last year Dr. John C gave me a set of Durafly Skymule floats conversion kit (Thank you again Dr. John!!!). So I decided to convert my Skymule to float plane too. It's a challenge for me (being a noob in model building). Finally I managed to convert it. I noticed my Skymule does not have float rudder to control. Although I can use throttle and rudder to steer, but I am worried it's not that easy. Then, I found others use 'Differential Thrust' to control the steering. With a bit of research (thank you Alan B who gave me ideas on how it works) , trials and errors, I finally got it working.
For others who are interested in setting up the differential thrust, here is how I did it.
Spektrum DX7 (or higher) - I am using DX9
Left Motor in Throttle (CH1)
Right Motor in another channel - I am using AUX4 (CH9). Assuming you have DX7 and up, you can use AUX2 or AUX3. I leave out CH5 (Gear) and CH6 (AUX1) because I am thinking to use it for other purpose in the future (like FPV headtracking, LED lights)
Assign a switch to toggle On/Off differential thrust. Differential Thrust will only be used in water steering. Turning off when take off and flying. I am using Switch A since I don't have landing gear.
Assign a switch for throttle cut both motors. You don't have to but for safety purpose (my fingers will thank me) I am using Switch H to perform throttle cut
Assign a switch to adjust the right motor speed. You want to synchronize both motors when performing Differential Thrust. I am using right knob to adjust the right motor
Programming the Mix function.
Here is the video with the setup instruction. :)
https://youtu.be/GOhIIhYPc1k
Where to get the float conversion kit - http://parkflyerplastics.com/cart/index.php?main_page=product_info&cPath=28_50&products_id=706
Side Note: Suppose to be look like a Grumman Albatross. But the final result looks like a bit of everything (GA+CL215+Twin_Otter). I don't know how well I build. I guess I will find out in our float flying event. Hopefully it won't turn up to be a submarine :P )
Oscar, I also use differential thrust for my Guinea Pig cargo plane. I tested it for ground steering, taking off, flying and landing. I assigned a switch to turn differential thrust on and off for testing its flying characteristic and found that there is no real advantage in turning it off. Here's a taxi test in my garage over the winter. Note the nose wheel is not under user control.
https://www.youtube.com/watch?v=ydttePbIgdU
Frank
Yeah.... so cool while taxiing. ;D
I look forward this year float flying event. :D
Frank, are you sure that's your garage? I don't see any tire marks.
Oscar, here's a DHC-6 Twin Otter in differential/reverse thrust action without any water rudders.
https://youtu.be/x2q_tLn8Dfw
I have been unable to set up differential thrust with my DX18.
Oscar, if I bring my radio and new twin-float-plane to the next meeting, will you try to help me?
Sure. :)
Quote from: gmcnic on March 20, 2016, 10:25:29 PM
Oscar, here's a DHC-6 Twin Otter in differential/reverse thrust action without any water rudders.
It's so cool. :D I doubt it can be done in my Skymule.
A big thank you Rob D who recorded my maiden flight. :D Here is the maiden flight.
https://youtu.be/2DpZ0eyxEZg
On final approach, too slow with sharp turn causing its stall (pilot error). Minor damage on the canopy with prop marks, aileron hinge went missing. :-[
And thank you Michael R for the flying advice with the twin motors. (turn with Rudder)
Lastly, thank you Dr. John who gave me the conversion kit. :D
Way to go Oscar- You conquered another milestone.
Ken
Thank you Ken
Oscar, thanks for all your posts. They keep me up to date with ROGO stuff and show your increasing skill in the hobby. Well done. :)
Thank you Bill