I built one today. I used stuff I had around the shop, so the materials aren't ideal. I figured if I like this thing, I can remake any particular part. I used aluminum for the outer collar (mistake) Aluminum is VERY sticky when in contact with steel.
I found some 2 inch round bars of bearing bronze on ebay for a pretty fair price. I'll rebuild the collar if I like this tool.
I did make the mid/rocker plate out of 4140, and man do I hate working with that stuff. I did 4 reamed holes instead of slots. This was mainly because I didn't think far enough ahead with my work holding.
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