TIG Tacks and Post-Flow

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Hi Everyone,I'm looking forward to easing my way into this community and its wealth of knowledge. I'm new to TIG welding and inert-gas welding in general.I bought a Syncrowave 250 dx after a TONNE (ya, an entire metric tonne) of research, which was the best compromise between functionality and cost (love the 60% duty cycle at 200 amps). I have a lot of questions about the machine but I'll save that for another thread.I've been reviewing lots of instructional DVD's and manuals and there's one thing that always confuses me... when you're laying down a bead, you program in ~ 1 second of post-flow per 10 amps. BUT when you're tack welding a piece, I've never seen anyone provide sufficient post-flow to each tack in order to avoid slag.I can understand the temptation to fly though your tacks, instead of waiting 10 seconds between each weld, but what is the best practice here?My thoughts would be that a tack doesn't put enough heat into the piece to require the full post-flow that you'd need at the end of a long bead. Am I close here?I've just been poking around these forums for the past couple weeks and its been an eye-opener. You folks really deserve a pat on the back for maintaining such an informed and up-to-date community; most online forums I've seen are like a petting zoo for *insert subject here*. Hopefully I'll be able to start contributing soon.Thanks for your helpT
Reply:Wait a minute...http://lamar.colostate.edu/~hillger/faq.htmlDo you mean to say that you did a full megagram of research? Howdy.The tig 'xperts will be around shortly. City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:My thoughts would be that a tack doesn't put enough heat into the piece to require the full post-flow that you'd need at the end of a long bead. Am I close here?
Reply:I have a watercolled machine and tacking depends on thickness of metal.  I go as fast as possible and the argon never 'times out'.  If 18ga or less i just fly, esp butt welds, i just roll the electrode across the seam, no filler; just hammer the pedal on move on fusing the existing metal.  Don't worry about argon it'll keep up with you.
Reply:Post flow for small tacks?None..Post flow for end of weld 5 sec.What is your post flow timer set at?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:tack doesn't put enough heat into the base metal to really worry, unless you're doing something very crack sensitive, or special.  Proper technique is to feather your tacks anyways so this should take care of any surface oxidation on a tack.We tacked and waited one-2 seconds. I don't adjust my post flow ever leave it about 5-8 seconds and that's good to go for me