Actually most of the way to cutting them to squares just finished cutting long way to get 3 strips, then put a couple of pieces through my bandsaw to cut them down the other way.When you cut out the blanks from that chunk of AL, are you planning to cut squares or circles?
I was thinking to use a Ø3.75 hole saw to cut the blanks. You will have to measure the saw to be sure there will be enough material left on the OD of the puck, it will be close. This will also give a center hole to start from.
I found the centers using the diagonal method which I'll use to set these up in the 4 jaw. I figure I'll cut the centers, then make an arbor to hold them centered while I cut the outside to size. I haven't decided yet if I'm going to cut the center too small do my arbor can have a key to keep them from spinning (then come back to cut the center to full size!), else I was just thinking super glue.
Too bad this wasn't designed with a woodruff key, it would make my decision way easier
I thought about that, but I couldn't think of a way to ensure that the set-screw ended up between two teeth that way.You could start by drilling and tapping for the set screw and put a channel on your arbor.