Brief Description: Fly Cutter and Hole Cutter Bits
I bought this fly cutter from Amazon for about $29 dollars. It has a 1/2 inch diameter shaft. It is pretty stiff and beefy. I used it at slow speed 300 rpm and it worked good. You gotta clamp down the material being cut.
Up date 5/30/09.
I bought a few of these hole cutter bits. They work great on aluminum. They have a cheap version which works and a more expensive version called bi-metal which have harder steel teeth. I try to buy the bi-metal versions if they have them.
