Question: Did it take a long time to repair the broken propellers? How did you do it?

Bernard Ennis answered on 11 Nov 2015:

It took a team of four guys around five days working in shifts to weld the propellers, inspect them for cracks and then machine them (by hand) to the right profile.

First we had to measure up the propeller to see how much material we would have to weld back on and then we cast new blade tips according to the original drawing. Then the broken tips had to be cut off with a grinding machine and then the new ones were butted up to the cut edges and held in place with very large clamps. The welding was all done by hand, layer by layer with one man at either side of the blade going from the centre to the edge. We inspected the weld from time to time with a special dye which seeps into the cracks and if there were no cracks, then we carried on until the weld was built up to fill the gap. After that we ground out the weld on the back and redid this including inspection.

After both blades were welded and found to ok, the guys got to work grinding the weld and the blade to the proper shape. The propeller has to be very smooth to avoid turbulence over the blade when it is rotating in the water.