I'm by no means am expert, but 3/4" material sounds way too thick for a scroll saw.

Edit: A five second Google search not only proves me wrong, but revealed these:

Scroll Saw Blades for Thick Wood, 12-Pack https://www.amazon.com/dp/B001G9POE6/ref=cm_sw_r_other_awd_nUqzwbANHWVNT