Hello all......

From some info I found on the scale ships forum, I decided to try my hand at making a replacement impeller for the jet boat. Luckily I found brass at my hardware store. The threads involving people making props from brass, really didn't apply to this application, since an impeller has such a high pitch, so I had to make each blade individually.

Mind you, this impeller was a test run, just to learn the basic technique, it's not perfect and not the way I wanted it, but I think its pretty decent for 3 hours of work.

So the I used brass piping, first I took my old impeller and covered the blade in tape to make a template. I had to guesstimate how much more blade area I had to add, since the hub is so much smaller in diameter. I transfered this template to the brass plate etched it and cut it out with my dremel, giving myself some extra material to work with.

Then using a propane torch, I soldered the first blade and then the second using silver solder. Tip here; cool the brass immediately with water to reduce softening of the metal.

After this, it really was more like art then engineering. I just used some vise grips and pliers and bent and shaped the blade, then using a micrometer I cut down the blades to a uniform radius. Overall the impeller is 31mm, instead of the originals 29mm, but I just finished and honestly enough work for the night, so I'll have to cut down some more tomorrow.

For the jet boats guys here. The benefits of this impeller over the plastic one are numerous. I plan to make the real one with 3 blades, which will load the motor more and reduce slippage. Secondly the reduced hub diameter dramatically increases blade area further improving thrust. And lastly using metal the impeller will not flex as much. You may think the brass is soft after all this torching and it being soldered on, but its actually quite hard to bend.

Question and comments are appreciated as well as any words of wisdom when it comes to shaping props.

~QS