I started to shape the propeller blank by cutting out the profile. Unfortunately, I noticed that the wood had warped slightly, and there were some gaps between the planks. Not enough clamping pressure, apparently. So, I cut them apart and glued them again.
While I was at it, I decided to add two more planks (for a total of six) so that the hub could be 4 inches thick instead of 3. Then I re-cut the profile and sanded it down. It's actually starting to look like a propeller!
Total Time: 13.5 hrs.