I recently converted an old beer keg that I got from my FIL. There was a lot of conflicting views on the web so I thought I’d share my experience.
I used a cut off wheel and abrasive flap disc from bunning for the top hole.
I then used a step drill and knock out die from keg land. These worked well with a battery drill on slow using chainsaw oil mixed with water.
I installed a 2200w element and a ball valve with a 90 degree elbow as the pick up. It leaves 3lts and picks up a bit of hop trub. This settles in the cold crash.
The element gets 38lt from 20 to 70c in 1 hour 10 and to the boil in 40 mins. The boil is a perfect rolling boil that doesn’t evaporate too much. (4lt per hour).
I use a pizza tray as a lid and a $10 Kmart yoga mat for insulating.
Including the bag and ratchet pulley from bunnings, it was around $125 for the build