I came across these pictures while looking for something else

This was a little trial boat made of thin styrene - probably .020

It used a Twin-turbo radio unit which was intended for blimps and has 2 channels each with Forwards, backwards and off on two sticks,

It was powered with 3x  50mah  sanyos ( a standard flight pack) and worked reasonably well except that I never made any paddle covers so the electrics got considerably splashed!
Motors were two similar flat mabuchis from Walkman tape drives wired to the motor outputs of the T/T


She was about 5 inches long, and would manoeuvre  happily in a pint measuring jug

Now sadly scrapped - but the concept could revive as I was given a contra-rotating toy heli for Christmas which did not make it to the evening before a rotor broke!

andrew

Hi Andrew,
Great paddler i really like the small scale. I also have a defunct twin rotor Helli that didn't survive too well, will you please keep us updated with your progress.
Many thanks
Malcolm