As a newcomer to this forum, (and to forums generally), please excuse any lack of forum etiquette, should I inadvertently become guilty of it.
I was fortunate enough to receive for Christmas a kit of Dumas' PT 109. While not a complete novice at model boat building, this will be my first "running" model. My question has to do with the selection of engine(s). I would prefer to stick as close as possible to the historical configuration, which would call for three engines. This seems impractical for this size of model. However, I do have two 5.5v motors (manufacturer unknown - presumabley the Asian area). Does anyone have any experience with the installation of two power plants in this model (or similar)? I would be particularly interested in some discussion on the appropriate ESC, batteries, whether one or two rudders are required, whether I should have props counter-rotate in relationship to each other (and if so, how best to achieve that), and so forth.

Many thanks in advance for sharing your expertise...

Look at my posts (#7 shows motor install) in this PT Boat thread. I scratch built the PT 188 at 1/32 scale. I have two MACK #3150 motors in the boat. The boat runs about 30 minutes on a single 7.2V 3000mAh NiMh battery. I installed two rudders, the rudder servo is near the stern. I am using counter rotating props, Octura 427's or 430's. You dob't need to have counter rotating props. The full size PT boats had three right hand pitch props - they all turned they same direction.

The MACK motors came with the motor lead wires already installed. Since I have counter rotating props, the blue and orange wires from the ESC are each connected to a black and red wire from the motors. The black wire from the port motor and the red wire from the starboard motor are connected to the blue esc wire.

Three? Impractical? Never!
See three Speed 600's in a slightly smaller PT at:
http://www.geocities.com/patspt41/

Pat M

Which size Dumas kit do you have?

Thanks
Steve

Originally Posted by 38special

As a newcomer to this forum, (and to forums generally), please excuse any lack of forum etiquette, should I inadvertently become guilty of it.
I was fortunate enough to receive for Christmas a kit of Dumas' PT 109. While not a complete novice at model boat building, this will be my first "running" model. My question has to do with the selection of engine(s). I would prefer to stick as close as possible to the historical configuration, which would call for three engines. This seems impractical for this size of model. However, I do have two 5.5v motors (manufacturer unknown - presumabley the Asian area). Does anyone have any experience with the installation of two power plants in this model (or similar)? I would be particularly interested in some discussion on the appropriate ESC, batteries, whether one or two rudders are required, whether I should have props counter-rotate in relationship to each other (and if so, how best to achieve that), and so forth.

Many thanks in advance for sharing your expertise...

Steve, its the 33 inch model.

Thanks to all for responses - most helpful!

Three Speed 400 motors would power it quite nicely. I powered my Lindberg 109 like this and it runs quite well, it is just a little smaller than the Dumas Model.

Thanks
Steve

Welcome, 38 Special! (You a handloader, or just like the old rock group?)

While building your PT, have a look/listen to this new sound system for model PT boats: Click Here

From this business:

JJC Electronics

Awesome sound bite, Kmot. Seems like the boat won't be complete without it! And yes, I do my share of handloading, altho the climate for us handgunner's is definitely turning chilly up here in the frozen north!