cf molded parts
Here is a project I tried that kind of fits your description. Its a copy of a spoke/lightened aluminum spinner backplate. The mold was poured from a semi rigid form of urethane. It happens to be a Smooth-on product, but others are available. Urethane are good for stuff like this because: it captures details well, it is 50/50 mix, it has reasonable viscosity, it demolds in a matter of minutes, it has some flexibility to demold the cf part when reverse curves are inevitable, it is relatively inexpensive. The only neg factors are when you require super accuracy or are involved in larger parts & distortionbecome an issue. The #1 part was so-so, the subsequent ones were basically perfect once the tow length formula was worked out. It was a finicky little part to make with the web intersections & varying cross section thicknesses but it was fun.