Twin Motor Mono Question

[b.mcdaniel.2009]

What's some pro and con's on having a twin powered large mono? Thinking a 47" Promise hobby deep V with either 2 Leopard 5692 1090kv W/ Castle HV ESC's or on a budget 2 Castle 1717 1580kv W/T-180A. ESC's.

[sundog]

If you mean surface drive, wouldn't one prop be out of the water when it heels over in turns? That might be hard on the esc, methinks!

Maybe not! Check this out: http://www.youtube.com/watch?v=Gl6Yg...eature=related

[Brushless55]

I think the twin 1717's would get it done real nice!
not sure of the speeds your looking for, but it should be fast

[b.mcdaniel.2009]

If you mean surface drive, wouldn't one prop be out of the water when it heels over in turns? That might be hard on the esc, methinks!

Maybe not! Check this out: http://www.youtube.com/watch?v=Gl6Yg...eature=related

I think as long as the drives are mounted close together the props should stay in the water I would think?

[b.mcdaniel.2009]

I think the twin 1717's would get it done real nice!
not sure of the speeds your looking for, but it should be fast

60-70MPH would be fine!

[Jesse J]

pros: very cool, motors/esc working half as hard, you have a back up in case one motor/esc/driveline/prop fail, that sweet sound of double power, no torque roll

cons: more batteries, twice the wires, twice the maintenance, limited by sizes of CR props, a lot of cash gets dumped in.

[sundog]

60-70MPH would be fine!

I bet!! Yes, Jesse J. was considering staggering the motors to get the stuffing tubes as close together as possible and encountered an interesting sympathetic 'assistance' phenomena http://forums.offshoreelectrics.com/...ighlight=jesse. Quite interesting - might even use less amps or get more torque because of it.

[Jesse J]

Interesting, yes. I have been thinking about that experiment and have some further insight. I have yet to try unplugging the Y connector for the ESCs. I am suspecting that the sympathy was cruising down the Y connection - power from the powered motor to the unpowered one along the radio wire. Still sympathetic, but maybe not related to the magnetic field. I have NOT observed this phenomena with inrunner motors ever! I don't think there will be anything for free, except maybe some "cushioning" - maybe bad on ESCs? probably not, but need data to be sure. Anyone with two Eagle Trees?

[sundog]

Interesting, yes. I have been thinking about that experiment and have some further insight. I have yet to try unplugging the Y connector for the ESCs. I am suspecting that the sympathy was cruising down the Y connection - power from the powered motor to the unpowered one along the radio wire. Still sympathetic, but maybe not related to the magnetic field. I have NOT observed this phenomena with inrunner motors ever! I don't think there will be anything for free, except maybe some "cushioning" - maybe bad on ESCs? probably not, but need data to be sure. Anyone with two Eagle Trees?

I don't think so. Since the motor was disconnected it was totally sympathetic, the esc's weren't involved. The outrunners, having the magnets under the outer spinning can is what I suspect allows/causes this. This is quite an interesting (phenomena) - it'd be nice for someone to build/use this idea - it has merit. Anything that can save amps or give more power for the same amps is always cutting edge!

[H2OCamel]

Jesse i think I have four eagletree's need to borrow 2? ;-)

[Jesse J]

Hey Chris, if you lent me one, I would then have two and could perform the experiment. pm on its way.

If you have one with 5.5mm bullets, that would be best. thanks!!

[sundog]

[b.mcdaniel.2009]

Wowo way over my head LOL.....Going to be innrunner's if I go ahead with this build. Glad you chimmed in Jesse, I know you've built a few twin powered mono's lol.....

[H2OCamel]

It on it's way! Can't wait to see the data.

[b.mcdaniel.2009]

Anyone else have any thoughts?