I used the small screwdriver that came with my dripper for a mandrel and tied a 28 guage coil 5 wraps
came out to .77 ohms worked pretty good.
I agree with the other poster that 28 and 26 is good-----32 is like human hair nd coil sags like the leaning tower
of pizza---------24 and lower seems like coat hanger and ramp up time is forever---heat is tremendous.