This is an "exploded" view of my rotor design. Leading and trailing edge foam cores moved out of position to show internal details.
This design features a cylindrical bearingless rotor root, with droop stop. Airfoil shaped pieces on inboard and outboard ends of rotor airfoil provide an equidistant path for fiberglass cloth layup, to minimize wrinkles where fabric goes around end of airfoil. You can see the (lead) tip weight at the most outboard portion of the leading edge airfoil. These tip weights were sand casted in the LE shape with a concave groove on the front to help position the weight against the leading edge rod. Leading edge foam core, tip weight and leading edge rod will be wrapped with fiberglass at +/- 45 deg layup pattern to provide torsional rigidity to transfer torsional moments from the pitch control horn (extension of leading edge rod) along the length of the airfoil. Will also include at least 2 layers of 0 deg layup to provide rigidity in bending, forming a "spar" out of the leading edge portions of the rotor.
The brownish section is a composite beam which distributes the large centrifugal tension forces from the inboard end cap (which is being pulled outward by the fiberglass fabric that will be wrapped around it - not shown) to the cylindrical flexelement which connects to the rotor hub (not shown)
Trailing edge will get a thin strip of alum inserted into a slot in the foam core to give some durability to the TE.
Below is a timelapse of the rotor tip casting, and a pic of the final product
Comments
Hi Randy, i remember some people posted rigid model rotor design, was that you?
I don't know if 3D printed HIPS dissolvable with carbon fiber will be useful for you. stratasys has its demo in car manifold and rims.