Building the prop

With no engine to play with I made a start on the prop. The only timber that I could buy in the correct size was pine from Bunnings. The grain was not very good but I chose the best out of many pieces. I thought pine will be strong enough as its going to get glassed anyway. So 6 pieces of 186mm x 19mm were laminated together using marine epoxy. After it had cured I used a belt sander to clean all surfaces ready to mark the cut lines. I triple confirmed the direction of rotation before marking the leading edge line, top flat area line and the trailing edge line from the prop drawings. Now the fun part, I had to use a hand saw to cut every 20mm down to the lines I had just marked on all 4 sides.

After this I used a chisel to remove as much of the timber away then a belt sander to get the surfaces flat. Then a orbital sander was used to round all edges.

Now I trimmed the prop to size by drilling a 1 3/8 hole in the bench and placing the prop over the hole. Then I put the shaft through to act as a pivot. A belt sander was clamped at 759mm from center and the prop was simply pushed through the sander. The prop was balanced and then glassed with 3 layers of 6oz. After it had cured I sanded smooth all surfaces and re balanced the prop and painted in gloss black.

To balance the prop I used an old broken router and ripped out all the magnets. I 3D printed a 1 3/8 shaft with a center bore the size of the router outlet. This way I can get very accurate balancing.