Hello Mike and gjamo,
Thank you for your suggestions. The disadvantage of going DC is that it requires the drill's case to be opened up and wires to be joined. Plus, I do not know which wire from the drill should connect with each of the wires in the controller. Wiring the drill up also has the disadvantage of making the drill a dedicated machine hardwired to the bead roller.
My copying the YouTube clips using corded electric drills is the ability to just use the manufacturer's plug into a controller. Then run through the controller into a foot operated on/off pedal switch. The drill can also be simply unplugged and used elsewhere.
I visited our local Jaycar and they no longer supply 240 volt motor controllers. They did have a foot pedal - which I bought. Interestingly their DC controllers only go up to 12 volts and my drills are all 18 volts. Plus, they need to be physically wired into the drill.
Of course I also revisited eBay tonight, and what was the first thing that comes up for my search? ... Accessed 10th December 2020 from,
https://www.ebay.com.au/itm/254667693197.
What is it? It is an Australian flagged
220V-240V Variable Router Fan Speed Controller Control Motor Rheostat 8A Australian plug. It bloody was not there a couple of days ago when I first checked without any success and made the first post in this thread.
Kind regards
Lionel