First time helmet build - EVA foam

[Amswickard]

I just moved away from cardboard and begun working with EVA foam to attempt to build my first rounded helmet, but I seem to be having some difficulties both in design and execution. When I cut I'm getting these little nubs and tears across the foam, even with a new blade. Is this normal and needs to be sanded down or is my blade duller than I think?


The upper portion of the helmet is giving me problems as well. I've tried several time to get it to look right but it always ends up looking wrong even though it's a simple design. I'm thinking that the problem may be that it's too simple without any extra detail to break up the otherwise round helm. Maybe building over a bicycle helmet would give me the mass i'm looking for?

 

[Zlurpo]

Your blade is duller than you think. Cheap blades won't work as well as nicer ones. EVA foam, especially the thick stuff you're using, starts to dull blades after only a couple feet of cuts in my experience. Get a knife sharpener, and use it very gently on your blade to restore it. That will get you many uses out of each blade.