sledgehammer with secret storage

this is a kit bash of
https://www.thingiverse.com/thing:5554440
and
https://www.thingiverse.com/thing:61205

I wanted a sledgehammer head that was hollow for the body of guitar. I wanted it to be able to access the cavity for storage. I reworked this so it can be really big by printing in parts and glued. It fits on a 8x8x8 print bed.

I've included my source files in AC3D .ac