I believe a machete was used to kill Nicole and Ron.
Sure looked like it didn't it. But, autopsy showed it was a small bladed knife. Mark Fuhrman found an empty Swiss Army Knife box in O.J.s' bathroom. It was apparently new. They never found the knife and O.J. wasn't talking.
OJ used a knife with two blades, I believe, because of his finger injury (Y-shaped).