Modifying Carbon Fiber Props

Two part question -- how does one go about modifying a stock carbon fiber propeller? The first part would be repitching the prop, the second part would be cutting down the prop to a new length. In looking at Noel Drindak's technical sheet of Nats planes in the latest Stunt News, it seems as though nobody really uses a "stock" CF propeller -- I was curious as to how one would successfully go about repitching and/or resizing these props.

Thanks,

Mike

Mike,

There are two ways people re-pitch carbon props.

By filing/sanding, and by heating/twisting.

Personally I prefer filing/sanding provided you aren't changing the pitch by mutch. I use a piece of permagrit tungsten abrasive glued to a piece of maple. Undercambered props are a little trickier, but you can just make a curved tool. A bit of emery cloth is usefull too.

I've not had consistant results with the heating/twisting method as I found the props had a "memory". A hot day was often enough for them to move back. I tried over twisting to allow for a bit of memory, but it was never an exact result.

Some people do have success with this method though.

As far as cutting to length, I use a fine tooth saw.

Your saw will last longer if you cut the carbon with an abrasive wheel.