Couple hundred tries huh? What's your secret.:-) How about a few years and a couple hundred tries, I was thinking more along the lines of using time as a measurement for this application since no one has time anymore.;-)
I did see some pics in one of the journals of a new hi si stainless wire that didn't require a purge. That was a few years ago though so I'd never find it. They also have some new rod with a flux on it that they are using in those ethanol plants. I heard it's a real bugger to get one to shoot clear though using that flux rod.