Kort Nozzle props

[rhodge]

I am looking for a Kort Nozzle prop system to run a 51" long x 14" wide cargo ship that will draft a max of 5" and loaded will be about 80 to 90 lbs. Can any one tell me where we can get the Kort Nozzle and any required materials and instruction to install the same?
Thanks for me and the kids in my class that are building the ship,
Bob

[bugfanatic]

Try harbormodels.com, they should have some. Also, I think Dumas has a running set with a Kort Nozzle. If I remember right they use it on their larger boats like the Mr. Darby. Let me see if I can find a link.... Here's one for starters: http://www.harbormodels.com/Harbormain/Templates/m14-propulsion.htm

[mjmsprt40]

I did it the hard way: When I had the Shelly Foss, I had a pair of nozzles made at a machine shop. They worked reasonably good, steerable, didn't require too much power to turn them. I had a lot of weight tolerance so I had them made of stainless steel. On a smaller ship, or one with less tolerance for heavy weight, I would choose one of the plastics.

The "Foss" model that I had came as a fiberglas hull, with a sheet of plywood and two sheets of plans. You come up with the way to make everything else. On this cargo ship, if I had to make a nozzle I would choose a plastic. You don't want a lot of weight on the extreme end of the ship. If you make one, make it with the leading edge of a larger diameter than the trailing edge, and make it so that the inside diameter at the propeller is only slightly larger than the propeller itself. The rudderpost should be at the maximum diameter of the propeller. This assumes a standard propeller setup, where the prop itself doesn't try to steer the ship. If you do the bit with the steerable prop, you're on your own. That means using universal joints and trying to get everything adjusted so it all works. Fiddly at best, I think, and I personally prefer to make the job as simple as possible to get the job done.

[mjmsprt40]

I have a suspicion that you're going into "uncharted territory" with your steering system, rhodge. I think what you're really trying to do is make one of those pods like they have on certain experimental vessels. The pod has a propeller on its leading edge so it actually pulls the pod-- and the ship it's attached to-- through the water. The ones I've seen are completely steerable through anything from 180 degrees up to the full 360 degrees. No one that I know of makes these things in model sizes, so--- you're on your own. Note that in full-size ships, they're using a diesel/electric system, so the pod has an electric motor in the pod itself that drives the prop. I have seen one recently in the BoatUS magazine for a pleasure boat, made by Volvo/Penta that appears to be a gear and shaft driven system. Here's the link:
http://www.volvopenta.com/ips/us