Anyone have a trick way of cutting open a oil filter w/out contaminating the results??

I suggest an oil filter cutter. Here is the one I bought.
http://www.aircraftspruce.com/catalo...lcancutter.php

I just put mine in a vise and cut it with a hacksaw. You will be able to tell the material from hacking it open. It will be on top of the element, and in my case was white. If you see the metal flakes of death, you will recognize them.

I use a hammer and chisel. Cut right at the steel base with the bevel of the chisel facing the base. Go all the way around and the can slides right off.

BT

A large tubing cutter...looks like a C-clamp with a cutting wheel....ask your plumber.

Sawzall at the base with the filter base down, cheap and effective. Pull off the canister and "read" your fortune or misfortune!!