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[Abuelo3]

Hello
I need some help here, before I burn my boat , I'm planning to put 3 cheap motor's at the Italeri PT,(plastic kit) in order to drive by one ESC(cheap too) I want that the 3 motor's run ad equal velocity and the props will be left handed, each one with one ruder.
Which will be the best way to wire that?
Thank in advance,
Feliz Navidad :angel:

[Tug-Kenny RIP]

It all depends on the voltage rating of the motors.

Say they are 12 volt motors, then you would have a 12 volt battery. The motors in this case would have to be wired in Parallel.

However, there is No guaranty that they would all revolve at the same speed.  It would be impracticable to wire three 4 volt motors in series, as the current fluctuations would be wild, due to drag and start up speeds. If one motor should short out, then the others would quickly follow and burn out.

Hope this helps

Cheers...Ken

[DickyD]

It's the Italeri PT,(plastic kit) Ken.
Think a 12v battery would be bigger than the boat.

[malcolmfrary]

It is unlikely that the motors will be an exact match, so the only simple way of ensuring that their outputs are equal is to gear them together. 
That said, bench testing the three should give the two closest matches.  I would use these as the outer motors.  Provided that the ESC can handle the power, just wiring the motors in parallel will work fine.  Any imbalances in power delivery will have to be sorted by making steering corrections, much like the real thing.

[Tug-Kenny RIP]

Do you really need to have three motors then ?  If it's that small, then one good motor would fit the bill.  If it's three propellers you want  ( for realism ) then just energise the centre prop perhaps, and have one each side freewheeling.

Cheers...Ken

[FullLeatherJacket]

I've just had a good long stare at the photos of Dave Abbott's conversion of this kit in the Model Boats Kit Special. It looks very much like there are two 6-cell AA x 2200 mAH NiMH packs, wired in series (to give 14.4 volts). The motors are MFA-Como RE385's while the ESC is an MTroniks Viper 15 (spit!). All three motors appear to be wired in parallel to the ESC. Dave has used counter-rotating 20mm x 3-blade brass props on the outer shafts and an anti-clockwise prop on the centre motor. At the speed these things are going to spin on that power supply then I doubt if a couple of hundred RPM difference in relative speed would have any noticeable effect on the performance of the model.
I can't help but think that if it's good enough for a National champion then it's good enough for most of the rest of us.
BTW Ken; in this context "freewheeling" = DRAG, and lots of it! 
Suit yourself.
FLJ

[Abuelo3]

Thank you very much, I will make first some bench test.
Happy new year