I know the Skills USA folks us AC for their E7018 open root pipe and plate welds.
I know AC will often mitigate arc blow.
But I would think AC might also create a "softer" arc with slightly less in the way of a penetration profile... This would be a benefit on lighter material where burn-thru is an issue... It might work the opposite for thicker material or procedures that demand a very specific perpetration profile that was attained with DCEP.
I still have an old AC only Lincoln tombstone buzz box in my garage that I at one time used with special 7018AC electrodes... Now it just sits, dormant, silent,, waiting for an opportune moment.
Kent,
What are you up to now? Always trying to cause some kind of trouble with the powers that be. LOL.
Smoother is not always Better.
As Lawrence points out, you must consider arc characteristics for penetration, spatter, and other side issues.
Then, again as pointed out, most do make a 7018 AC electrode. But, I believe most all of them WILL work on AC, but the AC formula works even better on AC.
Been a LONG time since I even tried running 7018 on AC. Now I will have to try it just to see. You always find a way to give me more projects. I haven't even finished my last one yet though I don't think it was you that started that discussion.
He Is In Control, Have a Great Day, Brent