RPM and motors

[Ronald Hallgren]

Hi all,
I have bought a Glasgow paddletug model from Graupner to my daughter
for christmas. Since the recomended motor for the model is rather
expensive here in Sweden, and I´m also planning separate drive of
the wheels, I wonder what RPM the wheels should have (the boat is ca
1 meter) and what type of motors should I use. Even if they too are
expensive I can get a couple of speed 720 BB torque from Graupner
for less than one of the recomended but an even cheaper alternative
is preferable. What about Model Motors Direct are there any internet
info from that company? they are said to have geared motors for
paddlewheelers. Any tips on gearing is appreciated.

Thanks

Ronald Hallgren
Sweden

[TEX]

Sorry I can't tell you much about em, but I've heard Ford Windshield
Wiper motors are good for use in tugs and have a low amp draw. As
for gearing, I hear all kinds of stories. Most recommend nylon gears
over metal due to the noise. I've also heard of pulleys an belts.
Sorry I can be more definitive. I could do some reseach an give you
better answers, but I fixing to make my annual pilgrimage to Texas.
Good luck. ... TEX in South Carolina

[KC6OLD]

The best I ever had was two motors from a pair of those Ride in cars they
sell for small children. 12 V Motors, with gearbox, used speed controls and 1.5
to 1 final on toothed belt drive.
worked great in pool, pulled 9.5 pounds stalled in bollard pull.(my fish
de-liar) never finished (destroyed when neighbor tried drycleaning, so was he)
Dave

[Tony Mattson]

re motors for Graupner Glasgow paddletug,

having been through a similar discussion recently when I joined the
group, I recommend using the search function on the Paddleducks website
- there is an abundance of useful information regarding paddle speeds.

Your Graupner kit is a 1:40 scale tug of around 40 inches so is not too
dissimilar to my own current project. (At the risk of boring other
members senseless) I'm building a 1:32 scale Reliant at present (also a
40 inch model) and have used two MFA/Como 919D 1481 motors powered by
12V. These come complete with gearboxes that provide an unladen output
shaft speed of 106 rmp. I understand that this will drop under load to
around 90-95 rmp per paddlewheel.

I have a picture of my "engine room" in my pictures folder <Kiwi
Paddler>. I've used brass pulleys at 1:1 ratio transmission and 'O' ring
belts to connect shafts to motors. The motors are mounted on sliding
mounts so that I have plenty of adjustment along the fore-and-aft axis
to tighten or loosen my belts or to accomodate different length belts,
and the configuration allows easy change-outs of pulley sizes to fine
tune paddle speed.

Please note that I am a budding technopeasant as far as the finer points
of engineering go so I have gone for commercially available motors for
my project. However there are some very interesting alternatives in the
Paddleducks message archives. For example, one low cost option might be
automobile car window winder motors - these are high torque, low drain
motors, geared down via rack and pinion. I've picked up a couple from a
wreckers yard and may use these next time (tks Derek).

Please do keep us all up to speed with your progress.

Tony Mattson