The 3M #2090 Scotch Blue painter's tape is just the best tape to make PLA stick to a cold or heated bed when printing.
Why 3M #2090 ?
- The tape sticks well to the bed
- The printed part stick well to the tape
- Leaves no trace on the printed part (compare to many cheaper green tapes)
- 48mm (2 inches) is perfect for regular MK1 / MK2 heat bed (4x2" = 8" = exactly 4 strips)