Sewing props has become a hobby of mine. It saves money and is a joy to do. In the first picture you see how I've carefully glued the parts together (it helps if the parts are all from the same prop but not entirely necessary) Then I drill a number of holes and use a durable wire to secure. Often the prop lengths have changed but that doesn't matter. In the above example the left side is shorter than the right. I'm using this one on my UCD and I simply reduced the degree of RH thrust I had on my motor. Works great. The second picuture depicts the underside of the prop. As you can see this is the less cosmectic side of the repair. Here is where the wires are tightened and where I do the all important balance. I use stick on weights but a word of caution. Once you get the weights in the right spot be sure and glue with 30 minute epoxy. They will not stay on with just the sticky tape if you exceed 10000 RPM.
Another benefit of this proceedure is unique. You can mix prop to get your own special pitch and diameter. I've actually made some successful hybreds. I start with a 16" 6 pitch and break them in half and sew a 14" 4W pitch on the end. Works great. Ends up something like a 14.5" and 5.25M pitch. You can't buy anything like that. It doesn't work for every application or airplane. But on certain ones, it's great.
Surprisingly this isn't all that difficult of a proceedure. (not brain surgery). With just a few hours of training you could be doing this yourself.
Thanks
Barry