using the vacuum former i made previously i made this:

it's not very fancy and actually didn't work well at all as a sheath.  so i kept playing...

this was a fun process...and got me interested even more.  the plastic sheet used was 0.030" polystyrene.  a nice cheap thermoplastic sheet. but not very durable, and quite brittle.  was great to practice on and play with.  but not for anything tactical

i kept playing though :)