In was thinking of a way to get the boat back to me if the winds quit without having to have a separate rescue vessel. How about using a bilge pump for propulsion. I would have 2 routings on the pump lines. I would use one when I was not racing with the club which would pump through a hole on the bottom of the hull and expell the water out the stern thus kind of creating a crude jet drive to get it back to shore. When I was with others and a rescue vessel was available, I would use the routing which would pump from the bottom of the bilge only and expell the water at the stern above the waterline so as to not have any water propulsion.
Have you had a problem with getting your boat back to shore on no wind days? I have found that RC boats respond to even the lightest winds in such a way that the boat will get to shore. I have never experienced conditions where the wind was so light that you could not retrieve your boat.
Having said that, the problem with your idea is that you would need an intake hole as well as a “jet” hole. Given the shape of the ODOM hull, you would need to devise some sort of tunnel for the jet hole (in other words, if you just put the tube straight out the bottom, it would not do a good job of pushing the boat). Then how would you cover that for racing so that your boat would be class legal?
You also indicate that you plan to use this pump to pump out water for club races (in such a way that it would not result in propulsion). Do you have a problem taking on water? If you do, then you should maybe try to solve that rather than adding a bilge pump. In my experience, ODOMs should not take on water under even fairly extreme sailing conditions. I’m not sure that a bilge pump would be class legal either. They can be rigged so that they turn on automatically which means they technically are not a radio controlled item. But the class rules may limit the amount and type of electronic equipment on board in some other way.
The weight of the pump and the battery would render the boat non-competitive. Putting holes in the hull and adding exra equipment would render the boat illegal as an ODOM.
Consider extra tape around you hatch if you are taking on water.
If you need a “retriever” boat, think about buying a ready-to-run r/c powerboat. You can find some for around $60.
I like your idea a lot, but I’m not sure how you’d turn it on without some other servo. Perhaps you could set up some kind of limit switch on your winch so that when you reel your sails all the way in / out it activates the pump.
Here’s how I envision it.
Download Attachment: pumper.JPG
Like the other guys said, it probably would suck for competitions, cause it would be illegal or something, but if you’re not competing, then whatever.
My other suggestion is a long piece of fishing line tied to the bow.
If you don’t realy care about keeping your ODOM competitive, Hobby Lobby Int sells a Motor/gearbox/shaft system with a folding prop that you can install in your boat. A small battery pack like a 270 5-6 cell pack should be be enough to bring you back to shore …unless you’re way out there.