Finally got all the bits together to fit a power drive to my mill x axis; a 12v window wiper motor, 110/220v -12v transformer, 12v PWM speed controller, some 3 core cable & some other bits 'n' bobs. I made up the framework from some 10mm aluminium plate, a couple of 10mm rounds. For the coupling I used a couple of spare sockets I had from an old imperial set together with a universal joint from the same set, to link the two I fitted a piece of 1/4" key steel with a spring over to keep the two sockets located on the modified leadscrew end & the motor shaft. I fabricated a cover from a piece of .5mm aluminium sheet I bought from a local DIY retailer & fastened on to the framework with a couple of 4mm SHCS.
It works quite well, giving me linear speeds of.. @ min.rpm - 18mm/ per min. & at the fastest rpm - 140 mm/per min.... max motor- speed 30rpm. The only thing that is concerning me is a after a few minutes operation (trial run) the motor seems to get overly warm so I was querying have I missed something in the build? I have tested the amperage... low rev amps- 2... max rev amps- 3.8, PWM speed controller input 12.2v output... 12.1v. Have put a torque wrench on to the leadscrew & it doesn't even register 1ft/lb to turn so there isn't a lot of resistance. Can anyone assist?

Have att. some pics for your perusal...