Paul
I was looking at some Titanium, Aluminum, and Ceramic Printing Systems.
I found this Planetary Gear printed on a 3d Printer, note companies are
now offering Titanium and Aluminum Printing, could this offer some
potential for future use?  Note in the YouTube it says has thrust load
potential also.  If some graphite could be added to Titanium printer
material, a self lubricating part, with light weight, high strength
would give you a reduction gear assembly for the prop.
http://www.youtube.com/watch?__v=ZghwSBiM0sU
<http://www.youtube.com/watch?v=ZghwSBiM0sU>
GF Curtis Jr.

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All depends on it's structural properties. Like powdered metal.

Paul Lamar



Actually Paul the DMLS (direct metal laser sintering) has proven to be
at least as good as cast material. They have successfully made short run
jet turbine blades in stainless steel and Titanium. Not forged level but
strong. The gear could be made but would need lots of post processing.
Likely to be cheaper to have a gear hobbed.
Bill Jepson.