Thanks Dub, I appreciate what you're saying and I've followed the thread with interest. But I just can't get the spaced coils to work without that nasty pop after the tanks been set aside for any length of time - be it overnight or 5 minutes. My spaced coils have been similar to yours, maybe slightly less spaced. But kanthal 28g not SS, don't know if that's important.
Tried tight wicks/loose wicks/long tails/short tails/different diameters, etc. You name it, I tried it. Tried talking nicely to the Doggy, taking Doggy for walks, swearing like a trooper at the Doggy (enjoyed that). But the Doggy just looked at me and said ".... spaced, not interested".
So for now I just do contact coils and I can happily report that my Doggies are house trained, bless 'em.