Have been trying to renew a certification. It's 6061-0 .063 and me another welder have been fighting subsurface porosity. We both passed it in previous years. But not as lucky this go around. We have tried so many things I am running thin on ideas and looking for advice. Here is what we are working with. -6061-0 .063 - 4043 1/16 wire-miller dynasty 300dx machine -argon 20 helium 5-3/32 thorartied tungsten 30 degrees sharp CURRENT CLEANING METHOD-acetone wipe of pieces -wire brush with new stainless brush of weld zone-file flat and remove bur from shear -wipe with acetone -wipe wire with acetone till cleanWe then put it in a holding fixture to weld the coupon which is made of steel and has copper bar in the center which is removable and has holes drilled in it for purging of stainless coupons. After welding we have been cutting them on the bandsaw and then sanding them up to 1500 grit to look at the ends under a magnification. We have been cutting them in shop till we get something that looks decent enough on the inside to send into the lab.Here is some pieces from today's attempts My phone won't focus enough to show the prosity in the inside of the weld but here is a old lab report Thank you for the help in advance. Sent from my iPhone using Tapatalk