G'day, George. I can't help much with your immediate query. But to add to Mal's (malb) suggestion, you can enhance alignment with a specific tool: Milescraft 30018 from the Turn Lock kit. It has concentric shafts, 1/4" at one end, and 1/2" at the other. Place the shaft in the appropriate collet, and use a bushing for the other. Then tighten the base. Then remove, add the appropriate bit and desired bushing. The Turn Lock kits should be available at Lowe's or Home Depot in USA.
And welcome to the best woodworking site in the world. I found it by accident too, and couldn't stay away.
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