I was struggling to rebuild my coils and found Coil wrapping | Steam Engine | free vaping calculators to be immensely helpful. I could get a coil to fire but it was like it was really boiling and not vaporizing. This takes a lot of the guess work out of it. And the advance view calculates surface area to really show what i was actually shooting for. Built my first coils that were as good as the shop built coils when i first bought my dripper. Kinda weird I was able to dial in my fogger before i could get a dripper hitting that wasn't soggy.