Progress!
While we're waiting on material quotes, we decided to burn some 60% scale rapid prototypes on the Z Corp. We've already cut these several times in CAM, but wanted to run our fingers over it before making a commitment:
Problem with material is I'm competing for 17-4 with the aerospace and medical industries, both of which have deep pockets. The trick is locking in a supplier at the right size and price.
The issue with the core (shown above) is minimizing mill time. The vane pockets as shown are smooth, or .001" step. Bumping this to .003" step would decrease mill time considerably. The surface would be slightly more "rough", i.e. not perfectly smooth, but this would also increase surface area by ~3-5%, which is a good thing.
At this point, the plan is get the prototypes together in time for testing at Putnam in April, followed by their formal debut at Winged Warrior in May. Watch for a complete assembly mockup in the next couple days...