observations on the fluidity of puddles (SS, Al, mild steel)

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i've been messing around with stainless steel lately and have made several observations. hopefully, the experts here will comment on them.Stainless steel takes a lot less filler dip.  is it because when i heat up SS into a puddle, not much of it vaporize?when i form a puddle on SS, moved it around a bit, then kill the tig torch, the under-cut isn't as severe as mild steel.a little filler goes a long ways when it comes to SS.  I bought 5lb of 1/16" 316L today.  I'm regretting not getting .045 or even .035its very easy to get the stack-of-dime look with SS, just as with aluminum... is this because the puddle cools so quickly as soon as i dip the rod?  mild steel puddles seems to want to stay liquid no matter how much filler i jab into the puddle.just some late-night, early-morning ponderin'
Reply:Stainless melts at alower temperature than mild steel and it does not disipates heat at a much slower rate.
Reply:stainless steel is more sluggish than mild steel. So yes that means undercut and the whole gouging mechanism won't be as severe. It also won't penetrate as much or wet out as nicely, which can create their own problems.the filler use shouldn't be any different between mild steel or SS what you're probably noticing is that you're getting less penetration on SS  so it feels like you need less filler.  both processes essentially transfer 100% of the metal to the puddle, the metals don't get vaporized in any noticeable amount (like 0.01%)