Had to give another quick reply because that wetwork helmet looks awesome! I haven't seen to many h4 builds come to life yet, can't wait to see the finished product!
Yes the wetwork will be worn, although it is too small as is. It's going to be cut into two parts and held together with ND magnets, hopefully by Wednesday you'll be able to see what I mean
The visor will be the half circle side panels.
The foam is called EVA foam, it't the kind you use for floor mats. 5 sheets are usually like $20.
UPDATES The wetwork mold is done!
Disregard the tear at the bottom, it won't affect the integrity of the cast.
Also, Discovered a neat little trick for this two part mold. Use Vaseline to keep the two halves from sticking together, then spray it with a little mold release. Holding the mold up to a black light helps you see what parts have and haven't been lubed. It might just save you hours of silicone surgery.