Very cool Ed! I like it! The 2nd one-- the black Retro with the flower-- that is classy!
As far as getting them centered, couldn't you use a disk sander or even a band saw to cut/sand the little doo-dad thingies to the EXACT square dimension of your blank-- and then to get a good, flat edge on your blank, mount it on the closed-end mandrel and shave the end of the blank to a dead flat for a good true glue joint, remove the blank, apply the doo-dad on that end, flush on all four sides to make it centered, grip it in a Quick-grip clamp until cured, and viola..... or ooops.... you tell me which reaction you have...[
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