Proper Post Flow for Tig

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How long of a Post Flow is Ideal for a Tig Tack weld?
Reply:I have mine set at 3 seconds.  For just a few short tacks, you might be OK with a shorter post flow, but that isn't a lot of gas.
Reply:Keep turning it down until your tungsten turns blue after a weld +3secs@150A on steel I'm usually at 8-10 secsBuy American, or don't whine when you end up on the bread line.
Reply:Hello atlascycle, the other folks have included good information. Consider that different diameters of tungsten will cool below critical temperature at different rates, critical temperature being the threshhold where oxidation will not be accelerated appreciably due to the heat and the lack of shielding gas. Then next consider the material that you are working with and how the "critical temperature" statement might apply there. Stainless steels, titanium, and other similar materials will benefit from extended post flow times at weld terminations.The comment with regard to the blueing of the tungsten is a good general rule of thumb if you are only considering the tungsten. It should be shiny or silver after welding has ceased and the post-flow has timed out. If you are working with fillet welds and have the tungsten extended out further than normal, leaving the tungsten in position on the joint while waiting for the time-out will aid with keeping it "clean" as this helps to retain the shielding around the end of the tungsten. Good luck and best regards, Allanaevald
Reply:Originally Posted by atlascycleHow long of a Post Flow is Ideal for a Tig Tack weld?
Reply:Nice find on the chart there, Dave. Best regards, Allanaevald
Reply:Thank you for the responses, I am currently trying to fine tune the Process for a new Job that I will doing. I have another Job that is an autogenous weld of a Stainless Steel assembly that I simply wait for the part to Cool below red hot and then I pull the torch.The job that I am currently trying to Fine tune is placing 8 Tacks on an assembly of two Steel stampings. the Attached Photo was on the the Preliminary Samples that I did. This was done using a Miller EconoTig at my customers facility. When I start with the production parts I will be using a Syncrowave 200, and hopefully will be able to reduce the HAZ, especially around the upper 4 welds to reduce the distortion of the assembly.I have not used the pulse settings on the Syncrowave for anything more than just playing around. Does anyone think that it would be beneficial?Thank you again for your responses.Jason Attached Images