Hello dffay, If this particular rod was designed to be run as an oxy-fuel welding rod the copper coating will likely not be the problem with trying to use it for GTAW purposes. There are other additives present that are used to promote cleaning and de-oxidizing in the weld pool when an OAW welding rod is being used. The GTAW rod has a different make-up to it allowing it to be suitable for that particular process. The variable I could see here would be the application of the welds, are these practice welds being made strictly to improve technique or are you thinking of using this rod to make welds on items that will actually be used for something? I imagine you have heard the statement regarding matching filler material to base material, this is a case where the gas welding rod doesn't match when being used with the GTAW process. To add to your original question, don't bother trying to take the copper coating off of the surface of the rod. Finally, even if the weld came out without porosity showing up in it there is an issue with the tensile strength of the weld, the Oxweld 7 only has a 45,000 tensile, the appropriate rod will have a 70,000 tensile. Hope this helps, aevald