I went to the mechanic and he said it sounded like the harmonic balancer was wearing out, like it was missing or something. I'm going to go back later when he has more time to do a better diagnoses.
edit: went back to the mechanic, and it's not the harmonic balancer. could either be the starter or the flexplate.
here is a video of startup, the metal chattering is what to try and listen for.
https://www.facebook.com/marshal.cor...46578162036899