After some waffling I decided to go the popular Pez route, but I wanted to refine it a bit. I ground out and polished a proper cavity in the nose, added the points to the base of the breathing grill, added the front edging to close out the "V" depression under the chin for a bit more screen accuracy, built out a base neck and added the plug, and of course rounded out the back of the helm and added the seam molding... then molded and recast a copy to sand/polish the bejeebus out of.
These 2000 to 12000 grit sanding pads are really awesome. Not only could I remove the mold lines to almost nill (afraid to drop it down further since I don't have a vacuum or pressure cast set-up... You start decapitating hidden air bubbles after a while) but I also removed the seam from the back-fill and got the entire thing down to a pretty wicked shine. After several hours of sanding I realized I was actually looking at myself.
If all goes well and my shaker table can get most of the bubbles out of the silicone I should be pulling some nice final casts tomorrow. (I'll leave the removable helmet mod for later... but I have to admit I've already thought it through.)
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