Hi again cudaxtreme, gas shielding parameters, gas passage integrity, quality of shielding gas, turbulence in the gas column, all of these things will have an impact on the finish welds that will result. If you are afforded the luxury of doing some testing with your set-up, try very methodically changing the different things that have an effect on the shielding, but try to change only one thing at a time. For instance, change to various flow rates and see if you can notice differences in the welding bead appearance and note any porosity or other inconsistencies. Generally insufficient gas flow and you will note porosity or possible discolorations of the finished bead face. Too much flow and you might also notice porosity as a result of excessive turbulence in the gas shielding column or possibly a venturi type effect similar to a carburetor which will mix atmosphere into the shielding gas resulting in porosity. In extreme cases where you are using a considerable amount of CO2 in the mixture you might have a regulator or flowmeter freeze-up due to high flow rates. In an instance such as that the high flow rates will cause the liquid portion of the CO2, while changing from a liquid to a gas, to cool so much that it will literally freeze the internal components of the regulator and possibly cut-off the shielding gas and prevent it from doing it's job. This may require a heated flowmeter. Experiment with gas nozzle to work distances, changes here can also affect gas shielding integrity. Contact tip position relative to nozzle edge distance can also have an effect, generally the contact tip should be recessed no more than an 1/8" from the edge of the nozzle and extend no more than flush with the edge of the nozzle, if there is an extension of the contact tip beyond the nozzle edge a possibility exists that turbulence and the venturi effect can come back into play. It is natural that you might experience a small bit of leakage of shielding gas at the end of the liner that is closest to the feed rolls, this is generally negligible and expected. Do consider using a liner that is sized according to the diameter of wire that you are using, this may not necessarily have anything to do with gas issues, but it will have an impact on welding performance overall. Hope that I may have included a little something here that will be of benefit to you in this circumstance. Best Regards, aevald

Hello cudaxtreme, I did think of one other thing that I didn't consider and include in the prior post. There is some additional hose that is inside of the feeder that makes the connection from the gas solenoid to the distribution block where the gun assembly generally connects. You might take a look at all of the connections and hose that makes this up and check for any leaks there as well. In some instances, due to any number of causes. A hole can get rubbed into this hose or possibly arcing could occur that might cause a leak in one of the fittings. The solenoid itself could possibly have an O-ring failure that could cause a leak. Just a few more things to consider. Regards, aevald