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My boyfriend and I just bought a Don Post imperial guard helmet. It has been badly cracked on the top but i think we can fix it using some sort of plaster and then smoothing it out. We would then like to make a mold using this helmet and make two additional masks. However, we are new to the costuming world and have now idea where to start. Any help would be greatly appreciated!!!

If you aren't going to wear the DP helmet and only use it as a mold the I'd use bondo to fix it. Sand the area down with a rough grit sandpaper then switch to something a little softer, but leave some texture there for the bondo to grab. Lay the bondo down and then sand it smooth.

On a side note, something to think about since it will be used as a mold, you could use the crack to your advantage and make the helmet bigger. The DP helmets are small and tough for some people to get their heads into. If you were to split the helmet into a front and back you could give a little more head room in the process. Use the bondo afterwards to repair and give the whole thing a smooth finish.

Ok we'll prrobally use the bondo to fix the crack, luckly both of our heads fit nicely into the helemt. Once we get that done, how should we go about making the mold? Are there any guides on making molds of helmets?