Making a power lift for my Milling machine from an old drill

I have a small milling machine but recently been finding it hard to wind the head up and down after straining my arm, so I thought it time to make some assistance. I tried adding a gas strut but found it had a sticking point when you wanted to come down. so I tried using a drill motor and a speed controller powered by the original battery. this worked better than a plug in power supply. It helped that the drill motor had a round body to grip. Anyway I'm very pleased with the result.
Geoff
https://youtu.be/sINkyXLbXo0?si=VBsIokBxnjOyXjsp

Clever addition! 

That's a really neat solution to a problem Geoff, well done.
Andy.