Home made Power Feed electrical question

[BH_N0mad]

Hi, I have a LatheMaster LMT25 mill and would like to put a power feed on it.
I picked up a DeWalt DW268 type 3 screwdriver. It has variable speed and forward and reverse with plenty of power. My question is the switch, I took it apart and there is a thyristor in the switch and the trigger has two sets of contacts that touch a strip on the board for speed control. I can't seem to get a good ohm reading of the strip to size a external pot. Has anybody every dug into this? It is a basic SCR circuit I think.
Thanks for you help
Tim

 

[BH_N0mad]

Ok, thanks, I made some progress with the switch on the drill and will see if I can make it work as I have it torn it apart to the point of no return..
If it doesn't work I will definitely give it a try.
Tim