Cox prop question

Hi Mark,

I have been prop shaping for years, I also like to scratch build all my planes so the custom bug is always biting.
The trick is take a photo of the prop then put it in paint or some photoshop type application and simply draw out the curves that look right for your needs. Next you get some paper packing tape on one blades and copy draw on the lines you liked. Cut out with sharp medium size curved cuticle type scissors / remove the tape and match it up on the uncut blade the rest is all in the shaping work file in the foil and buff to a shine with fine sandpaper use the same technique in your shaping style for both blades you will be surprised what you can do by hand. After you're done and you feel your best efforts have been made to match up the work on both blades (balance the prop) and fine tune some material off the heavy side.
The prop shown took me less than 30mins (being so small) from design to finished prop.  

The modified modernized prop puts out more rpm it is still a 3in dia prop providing good thrust yet the swept (sharper) leading edge increases the rpm and the relief in the trailing edge of the tips expound the rpm even further for the TD .010 this made for a huge jump in rpm depending on the nitro content you can expect a 1,800 to 3,000 + rpm increase over the stock prop.


The plastic flexible props are not easy to shape you have to really want a robust prop to endure the extra shaping work.
The 3.3 x 2 is a hard glass/plastic prop easy to shape.