150% MSBP. Mini Scout Biplane, Not so Mini!

Wildthing

Legendary member
I have never done a 2 engine plane so ill be asking lots of questions but if you guys can show me how to do it I'm game. I have a matching pair of e-max MT2212 1000kv motors and I have 2, 30 amp esc's. BUTTTTT. I was thinking, how about 2 e-max motors on the wings and the big Turnigy 3536/5 in the middle?
Easy enough to do with your motor pods, I have to find the thread and link to my 3 motor combat plane I called Shredder. Running 3 and the size of plane I would try to make room for 2 minimum 2200 3S batteries , just need to get you soldering iron out to make a connector for 2 batteries and 3 motors, the rest is easy. The wing mounted motors those you want counter rotating props.
 

sundown57

Legendary member
Easy enough to do with your motor pods, I have to find the thread and link to my 3 motor combat plane I called Shredder. Running 3 and the size of plane I would try to make room for 2 minimum 2200 3S batteries , just need to get you soldering iron out to make a connector for 2 batteries and 3 motors, the rest is easy. The wing mounted motors those you want counter rotating props.
ohhh. yeah , this is starting to sound very cool. I have matching pair of both 3000 mah and 3300. so I'm sure I can design it to fit 2 in somehow. I need to figure out the best way to mount the wing motors. like what kind of a pod i should use.
 

Wildthing

Legendary member
ohhh. yeah , this is starting to sound very cool. I have matching pair of both 3000 mah and 3300. so I'm sure I can design it to fit 2 in somehow. I need to figure out the best way to mount the wing motors. like what kind of a pod i should use.
Here is a link to where I started building Shredder. The only real fun part is you have to plan your wiring and somehow make them all meet in the middle :D . Usually it does involve some creative fishing , heck on one plane I ran a thin coated picture hanging wire through the wing before I folded it so once folded I just tied it to my motor leads and pulled them through.

https://forum.flitetest.com/index.php?threads/bloody-baron-going-smooth.58059/post-495313


If you want to get fancy you can program thrust vectoring into the side motors (depending on your equipment you have) . On Shredder I did mix in throttle for them on a different channel and had a kill switch just incase one got knocked out.
 

sundown57

Legendary member
If you want to get fancy you can program thrust vectoring into the side motors (depending on your equipment you have) . On Shredder I did mix in throttle for them on a different channel and had a kill switch just incase one got knocked out.
now the English version, please.
 

Wildthing

Legendary member
If you want to get fancy you can program thrust vectoring into the side motors (depending on your equipment you have) . On Shredder I did mix in throttle for them on a different channel and had a kill switch just incase one got knocked out.
now the English version, please.

Well my radio is just a cheap FlySky so I don't have many options but even your should have a kill switch that you can activate. My main (center) motor I mixed channel 6 to the throttle and it was plugged in there, the two wing motor got plugged into channel 3 and then with the kill switch activated I could turn them off any time and the center one keeps going. Thrust vectoring is more mixing and mixed in with the rudder, eg., when turning left with the rudder the left motor slows down and right speeds up and visa versa turning right. I didn't do that on Shredder , I just kept it normal .
 

sundown57

Legendary member
looking at pics of twin-engine biplanes it seems they all put them close to the fuselage, id like to figure out a way instead of adding the weight of 2 more pods incorporate them into a heavy-duty double-wing strut. added support with less added weight.
 

BATTLEAXE

Legendary member
I have never done a 2 engine plane so ill be asking lots of questions but if you guys can show me how to do it I'm game. I have a matching pair of e-max MT2212 1000kv motors and I have 2, 30 amp esc's. BUTTTTT. I was thinking, how about 2 e-max motors on the wings and the big Turnigy 3536/5 in the middle?
What's better then two motors you ask, three of coarse. Hell yeah man and it would be so era scale as well
 

BATTLEAXE

Legendary member
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looking at pics of twin-engine biplanes it seems they all put them close to the fuselage, id like to figure out a way instead of adding the weight of 2 more pods incorporate them into a heavy-duty double-wing strut. added support with less added weight.
t you go with all the cool ideas, I am getting excited for you to build this thing
 

Wildthing

Legendary member
looking at pics of twin-engine biplanes it seems they all put them close to the fuselage, id like to figure out a way instead of adding the weight of 2 more pods incorporate them into a heavy-duty double-wing strut. added support with less added weight.

You could make a strut that incorporates the motor mount right in the middle so you are giving the wings the structure they need plus a spot to put the extra motors. This is my X wing as an example.
2019_0128_065106_001.JPG
 

sundown57

Legendary member
another thought,, the 1000 kv motors need like an 8 or 10 inch prop. But I have 2, 2212, 2200KV that use a 6 inch props. They would actually sit inside the wings. but I only have CCW props for the 6 inch. so would it work if I put 2, 6 inch in the wings turning CCW and the big motor in the center turning CW?
 

Wildthing

Legendary member
The closer you keep the motors to the fuse the less strength you need to build into the wings , if you hang the weight out on the wing tip you will need to be extra strong. Plus with the weight more central the flight characteristics will be better.
 

Wildthing

Legendary member
another thought,, the 1000 kv motors need like an 8 or 10 inch prop. But I have 2, 2212, 2200KV that use a 6 inch props. They would actually sit inside the wings. but I only have CCW props for the 6 inch. so would it work if I put 2, 6 inch in the wings turning CCW and the big motor in the center turning CW?
Hard to say how much torque roll you would have, having the counter rotating ones there is zero torque roll. With having the center one as the main power it might hide the other two guys .
 

sundown57

Legendary member
The closer you keep the motors to the fuse the less strength you need to build into the wings , if you hang the weight out on the wing tip you will need to be extra strong. Plus with the weight more central the flight characteristics will be better.
ok so there is a good reason to go with the faster smaller 6-inch props. Now I just need to find a forum that has a bunch of really smart guys that know cad and stuff to design me a strut that will hold a motor, fit in between the wings and that I can make without a 3d printer. wonder where I can find that forum?
 

sundown57

Legendary member
Hard to say how much torque roll you would have, having the counter rotating ones there is zero torque roll. With having the center one as the main power it might hide the other two guys .
in my thinking no matter how i set it up 2 motors will be turning in the same direction. so what would it matter what 2? plus if i have a 10 inch and a 6 inch both turning in the same direction that other little 6 is going to have a hard time countering it.
 

Wildthing

Legendary member
Simple cross mount is all you need and cut out a plywood motor mount you epoxy to the strut Attached is the X wing strut and the cross mount to give you an idea of what to build. The motor mount you can use 3/32 plywood like I use to before I got the 3D printer :D .
 

Attachments

  • Strut Brace.pdf
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  • Motor Mount Cross Piece.pdf
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  • std_motor_mount.pdf
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