need some help from some salty tig welders

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Alright, long story short I'm trying to pass a 6G test on stainless steel 316 grade.  I've been to a college here in TX to get my certification.  Have been welding pipe for about 3 years.  Didn't have to pass a 6G welding test though.  The owner let me use a positioner and I basically welded it flat and uphill.  I recently lost my job and tried testing out for a great company the other day but had some issues.  I think my biggest problem is setting the purge...IE  From about 6:00 to 3:00, I could never get penetration on both sides and the stringer basically was sucked back.  Would the purge have been to high?  It sucks cause I've learned to walk the cup and don't really have any trouble working around it.  It's just that I guess I'm either not adding enough metal or need to make some adjustments for each quarter.  Can someone pleeeaaassseee give some pointers?!?
Reply:Establishing a GTAW root bead with adequate reinforcement is relatively easy with 300 series SS.If your purge was too high, problems at root close out would be evident. Did you have a relief hole in your pipe ends to allow escape of purge during close out? Normally excess purge will not "flatten" the root bead until 12'o'clock close out on a 6G VU pipe butt, however high purge pressures may push out a root bead during pass 2 welding.Under ideal conditions, a flush root bead is OK as fill / cap pass weld shrinkage will often cause the flush bead to become reinforced, or "pop"A flush or slightly concave root bead is no cause for rejection, even ASME B31.3 severe cyclic criteria allows this feature, provided the wall thickness is not compromised. The cap pass reinforcement makes up for any root concavity. Developed films show weld contrast lighter or equal to the base material under these conditions.If additional root bead reinforcement is desirable, try:1: adding additional filler.2: increasing root gap.3: Reducing amps and travel speed.Whilst walking the dog is good, it can increase base material dilution at the root, effectively flattening out a root bead.I wouldn't be too concerned at this stage, provided your root bead is nice and clean with good toe fusion, small adjustments in your technique should improve the visual appearance.Good luck
Reply:What is the flow rate on your purge?Nice post there Chris. very informative.I'd rather be hunting........USE ENOUGH HEAT.......Drifting around Aussie welding more pipe up, for something different.....wanting to get home.