Finishing Darth Nihilus Masks
Here are the steps I use to finish fiberglass masks:
Be sure to take precautions before sanding fiberglass. It is unhealthy to breath the dust, and the fibers will really irritate your skin if you don't cover up! Wear a good respirator (not one of those silly paper dust masks), goggles that will protect your eyes from blowing dust (not just glasses), long sleeves, and gloves. Nitrile gloves are great, since they protect your hands but still allow a good grip. Trust me, you WILL regret it later if you don't cover your skin! I like to wear a Tyvek painter's coverall... just zip it on over my clothes, sand a bunch of fiberglass, and then brush off the dust (or use a blast of air from my compressor) to clean off the coveralls before I unzip them and emerge all clean!
1. Sand off the extra material around the outer edge using a mouse sander with a rough paper such as 80 grit. A belt sander is faster, but you have to be careful not to take off too much material. I like to take the extra material off with the belt sander first, and then use the mouse to get in close and smooth things out.
2. Use a Dremel with a wheel drum sander (rough grit) to take the extra material off the eyes and nose. I generally ignore the center and focus on the outer edges. Trim those down, and the center falls out.
3. Run your fingers (wearing gloves!) around the inside surface, and use the Dremel to trim off any bumps or prickles left by the fiberglass cloth/resin. If there are any spots that came out excessively thick, you can also use the Dremel to knock them down a bit.
4. Using rough wet/dry paper (150 or 300 grit or so) under slowly running water, sand the cut edges to round them off and wash away all the dust from the Dremel and sander. If there are any bumps on the front surface, sand them down. Let it dry.
5. Fill any visible air bubbles or low spots with putty, and let the putty cure. I use 3M Acryl-White Glazing Putty, or model putty from the hobby shop. Try to make the putty application as smooth as possible. Leaving a big lump just means more cleanup time later.
6. Lightly wet sand the mask with 400, 600, or 800 grit to take off any last bumps and smooth the edges of the putty. (Fine grit won't take off the indentations for the red paint as long as you don't scrub at them.) Dry.
7. Spray front and back of mask with primer, preferably white. Dry between sides. A large Dixie cup with some sand or bolts in the bottom to keep it from falling over holds the mask nicely while painting. I use Rustoleum 2X Flat White Primer, from Home Depot. I always spray the inside first, and then the front of the mask.
8. The primer usually reveals some spots you missed before that need a bit more sanding or filling. Take care of those spots, rinse again if needed, primer again if needed, and dry. After that...
9. White paint! I use Rustoleum Satin White
10. Silver paint! I use two coats of Testors Enamel Steel. I've fund that true silver usually looks too bright.
11. Red paint! I mask the lines with Tamiya masking tape to keep the lines looking good, and use three coats of Testors Enamel Flat Red with a few drops of Flat Black to darken it a bit.
Hope that helps!
Darth Nihilus and his apprentice, Darth Shredder