I decided to use an older Troyke 9" rotary table I had on hand as the basis for a welding positioner. I made an adaptor plate to mount it on a drill press rig with a 12" high column. This gives it the ability to tilt 90 degrees to either side, and swivel to either side as needed to distribute the weight.
It will be driven by a variable speed gear motor through a timing belt and pulleys. If necessary, the speed range can be tweaked by changing the size of the timing pulleys.
At present, I'm working on a mount that places the motor out of the way under the table. Waiting for some steel to arrive.
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