The wear groves in the prop shafts were repaired with a molybdenum thermal coating. The process consisted of grinding back the shaft, spraying on the molybdenum thermal coating, then grinding the shaft to size.
The photo below shows the finished shafts. It was not necessary to remove the bearings etc on the shafts which saved additional expense.
The repair was handled by Sam Cobb of landtosea.co.uk, he uses a local factory, I don’t know which one. It took 3 weeks in all. I was charged £290 plus VAT per shaft. Ropewalk were very happy with the quality of the finished shafts. They have been refitted and are in use and my boat launched yesterday, yippee.
I was told the repair should last longer than the original shafts, since I got 1500 hours out of them it should mean I’ll never have issue again. Sam told me the process is used to repair wind turbine shafts, IPS drives among many other items.
Also a big thank you to Charlie for letting me have a reconditioned steering ram to replace one I found leaking on the night before launch, it got me out of a hole.