Hey guys, for an engineering project I have to build a boat that can transport an orange approximately 300 feet as fast as possible. The actual boat is made out of a styrofoam block, measuring approximately 18" long by 12" wide and 6" tall. It will have a 6v 10,000 rpm motor, accompanied by the necessary 6v battery. All in all i'd say it weighs about 5 lbs. I am looking for help on what prop would best be suited for this task. There is about a $5 budget on the prop. If anybody can give me some suggestions, or point me in the right direction it would be much appreciated. Thank You!

offshore electrics have carbon filled props for about $5 but the smallest is 40mm in dia
most of our motors spin in excess of 20,000 rpm and closer to 30,000 or above
maybe some one who has scale boats mite be able to help

Try to find a Robbe dealer, you can get some decent scale props in that budget. Also look for Graupner K series. They start at 31mm for the M4 type

If the $5 is indicating that you are at the end of your budget than this won't matter but you could also consider gearing the thing up, so the prop turns I higher RPM. Some nylon gears would work as it doesn't have to last a long time.

If the budget is only 5 bucks then you maybe in trouble as i'm sure your going to have to try a few diffrent ones before you find whatever suits your need the best. I do recall reading in the Mini Rio thread about some guy named John thatssome kind of an engineer and he supposedly can steer you in the right direction when it comes to prop set up. Im newish here (to boats as well) so hope my info is good for your project.

Rock On!!!
JRockZ

Hmm, 10k rpm on 6v, sounds like a scale prop to me too. Check ebay under rc parts and acc. then under boats, you should find something there for your $5.