gear primitive geometry puzzle

[Heimhenge]

I needed a quick and simple 4-bladed turbine, and hit on the idea to use the gear primitive tool with a "reverse" taper on the "teeth" (attached image). Felt pretty clever until it came time to apply surface properties. The small 4-pt polys that make up the edge of the turbine surfaced fine. But the two faces of the turbine (16-point poly?) would not accept a surface. They appeared to have a surface in Modeler, and showed surface properties in Surface Editor, but were transparent in Layout.

The surface was a simple single color. Nothing fancy. Tried multiple times. No joy.

Finally hit on a workaround. When I tripled those face polys, the surface worked.

Question 1. Apparently LW 9.6 will create polys with as many points as required to generate some of the primitives. Could my messing with the gear properties, creating reverse taper and a non-convex poly, somehow have confused the Surface Editor? Or might I be missing something obvious here?

Question 2. What would be the easiest way to break that complex poly into many small ones? Tripling worked OK for me, and actually put a nice bevel on the blades when I twisted them 20 degrees. But if I wanted a smoother propeller style blade, I'd need many more polys than tripling gave me.

Thanks in advance for the wisdom.

Heimhenge
XP Pro SP2
Intel Quad Core 2.6GHz
2 Gb RAM
NVIDIA 7800GS

[wayne1 huffman]

Were the normals flipped? That might make them appear transparent.

[Heimhenge]

Nope. That's one of the first things I checked. I've been further exploring this issue, and believe it's a bug in the way the gear primitive is interpreted by the surface editor. A normal gear (with a convex perimeter) seems to work fine.