large scale boat help

[Aubie]

My wife and I are planning on building a replica of the Orca boat from the jaws movie. The twist is we are planning on blowing up the plans to a 90 inch length and a 30 inch beam. The construction is no problem but the running gear for something of this size is. We will be ordering the plans tomorrow and start construction next weekend hopefully. We are open to any and all suggestions on running gear.

[Umi_Ryuzuki]

Well if you haven't already had a look around the boards, read thru this thread.

http://www.rcgroups.com/forums/showthread.php?t=221839

It talks about some of the potential motors that you could use.
However, a 30 inch beam soulds like a lot of water to move.
Using an old wheelchair motor might be an option.
Also, I have seen where large scale modelers were satisified with using the
propeller from an electric trolling motor mounted under the hull.
It is not scale, but provides plenty of power.We have a twelve foot Fletcher class destroyer here in Portland that runs on one of these motors.
And it handles beautifully.

Have a look at Robert Voorhees' PT Boats. :)
http://www.rktman.com/rlh/gallery/robert/robert.html

[Aubie]

Thanks Umi, We will probably go with the trolling motor. We have some time to make a final decision but with the width of the beam the trolling motor would probably be best suited.

[P. Tritle]

Aubie, When you get the big Orca project underway you will have to post the construction thread. I'll be watching it closely, sounds like a great project, and will be an IMPRESIVE "model".
PAT

[Ron Olson]

If you decide to go with scale running gear, Junkyards can be a great source for electric motors. I saw a 14 foot Warship that was powered by power seat motors from a Plymouth Volare' a few years back.

[English Nige]

Hi everyone,
Im new here - so hello to everyone from England !

I noticed this thread with interest as I always admired the Orca in the Jaws movie. I thought she was a very good looking craft.

A lot of people here in England who make large models, have become attracted to using car windscreen wiper motors or car heater blower motors. They source them from scrapyards and they are usually very cheap. As to power, because they come from a car, it seems logical to use a car battery for the main drive.

Im currently building an 8 foot long model of the CPR ship Empress Of Asia and I intend on using two car batteries for her. I figure that if she's going to need about 20 kilos of ballast - why not have it doing something !!! :D

There are a few pictures of her here:-
http://groups.msn.com/WHITESTARSHIPS/mymodelspage3.msnw

Hope the Orca project goes well - I'd Love to see some pics !
Nige