I've had a few messages asking about my Playdate crank mod so I'm documenting it here. Do this at your own risk obviously.

• Get hold of a plastic Davies 1900H knob clone. It needs to be all plastic with an array of fins on the inside; not the type with a metal inner. I got mine from eBay
  
  
  
• Remove the crank from the Playdate: using a SIM ejector tool or pin to push the yellow axle out. It's a friction fit so it should should slide out easily.
  
  
  
• The crank axle is reused to hold the Davies knob in place so put it back in the mount. Using a small screwdriver/implement prise open a gap wide enough to hold the spindle tightly on opposite sides of the knob. It's a friction fit again so you don't want to make the gap too big, start small and work your way up until it fits nicely. Don't push too hard or you'll risk breaking the crank mechanism inside the Playdate.
  
  
  
• That's it, it's fully reversible if you ever want to put the crank back.