Avoiding trouble with 7018 electrodes

7018 are really nice welding electrodes. They can however be
a bit difficult to ignite. That is until you understand what's happening.
As a lit electrode goes out there forms around the tip a ball of
non-conductive flux. All you need to do is remove this with a file
and you're good to go. I can't claim to have invented this method
but I'll include it for anyone learning to stick weld 7018.