frequency

Has anyone had experience with one of these? I have an opportunity to get one of these. I would need to tig weld with it, anodized aluminum. What's the availability of a high frequency box for this machine? Is it worth bothering with?

I'm about to change over to the royal purple 4stroke oil I bought for my predator but how long do you guys run synthetic oil before you change it out? At $9 a quart I hope its not very often :smile: