In the process of adding a motor drive to a rotary positioner kit, that was originally designed to be driven my a cordless drill motor. I bought the positioner kit knowing this, and never intended to use the drill motor, as that seemed pretty useless. Welded an adapter plate to one of the shoulder bolt axles, so it all moves as one unit, and happy with how it works. The combo of the 100 RPM 12VDC gearmotor, and the 40:1 gear reduction in the positioner, makes for a turntable that rotates at 0-2.5 RPM. Next is to make an enclosure for the motor, and a control box that will have the speed/direction control board and the battery( this will be powered with a Milwaukee M12 tool battery ). A foot switch will start/stop the table.

Before sinking too much effort, decided to run a test bead in DC and AC to make sure the HF start and/or AC freq didn't screw with the electronic speed control and motor. Didn't miss a beat, so will proceed with the remainder of the project. First beads ever using a positioner. 

Edit. Thought I'd add a rundown of the major parts I used to motorize this Weltables rotary positioner. My subscription here expires in a few days, and not sure if I'll be renewing. Some work came in, so I won't have time to finish this project until next week. 

Motor-https://makermotor.com/pn01007-100-10mm-2-flat-shaft-electric-gear-motor-12v-low-speed-100-rpm-gearmotor-dc/

PWM Speed Control-https://makermotor.com/pn00218-cyt13-25amp-7v-58v-high-voltage-dc-motor-driver-speed-controller-md25hv/

I got the flex coupler, 12V battery adapter, and foot pedal on Amazon, and should be simple enough to find in a search. I had to turn the hex end of the positioners shaft on a lathe. You could also simply adapt a socket to the motor shaft.

Edit to add: Another follow up, with a few photos of the final assembly of the motor housing and battery holder. Positioner works great and has plenty of torque. Set a 60 pound chunk of 1045 bar on the plate, and it rotates it smoothly at any speed. Very happy with it.

Yesterday's project was welding up today's V-day gift for The Woman.

Edit. I thought that I'd posted this in the questions but ended up in General. So I thought I'd tag Matt Hayden in case he doesn't see it here. 

Not real crazy about what I saw when cut and etched some sample 2F welds with the dual shield at 25V/250 IPM 35 CFH C25. They look OK on the surface, but about zero root fusion, and pretty shallow penetration. The etch wasn't great and didn't photo well. The 1/4" material was spotless clean and square; no rounded over sheared rolled edges. It was belt sanded square. Maybe I was traveling a little too fast? The throat is definitely under 1/4". Thoughts anyone?

Photo 1 cross section is pull beads top left/bottom right, and pull top right/bottom left. Photo 2 is pull, and Photo 3 is push.

Edit to add: Not sure what the hell is going on. Ran two more beads. Photo 4 is 25/250 and photo 5 is the Auto Set suggested 22.9/265. Slower travel speed to build up a bigger bead, which it did, but as you can see in the last photo, the root fusion in both is terrible. Squashed it in the 40T press and it held up OK, but I would hope so, welded on both sides.