ORIGINAL: f3a05
If you solve this, and somehow end up with the spare inner bit, I'd love to know how much it weighs?
Well, I had to check. I did some thumbnail calcs on a 45 size pattern plane I have drawn up and it looks like that one would be 1.25oz or so. So a full 2M size core might actually weigh a noticeable amount. I would definitely eliminate that core if it is 3oz or more of dead weight...
Mark