Hi Joebob,
Regardless of whether you use stringers or weave, the one most important tip I can give you is to make gravity work for you instead of against you! By this I mean ALWAYS keep your puddle horizontal, never square to the joint (as with a 5G the puddle is square to the joint) after the root bead is applied! As you add passes and the base metal temperature increases, so will the affects of gravity on the puddle especially if you use a weave. Even with GTAW stringers, if you run square to the joint you will experience a sagging or the puddle’s lower edge (“cup-walkers” have a little less problem because they can control their heat input better then “free-handers). A puddle square to the joint will sag or in worst-case scenarios, cause an overlap of the puddle’s lower edge and cause undercutting of the top edge. (*Undercut may or may not be a cause of failure for your test. Ask and find out before hand.) The fillet attachment of circular reinforcing pads on vertical vessel walls comes to mind as good representative joint that requires a very similar 6G technique for welders to experience the effects of gravity on the puddle. In addition, this type of fillet weld (circular) is a good way for an inexperienced welder who has to take a 6G to practice on prior to testing


The 6G, regardless of coupon size or welding process (SMAW, GTAW, GMAW, or FCAW), was my “signature” test weld throughout my welding career. When I broke into the trade in the 60”s my instructor told me 3 out of 100 welders he tested tried the 6G and only one of them would weave it. I always wove mine from that day on but I believe stringers are easier for individuals that aren’t used to the position and just plain need to pass to get the job!

Well, to say the least I would say with my experience that as long as both "shoulders" of the tube are covered, it shouldn't matter how many passes are on it...and your best bet is to string the whole thing out unless you're real good at waliing the cup....I'll walk the cup on 2" sch. 80 stainless tube in 6G, but that's it as far as schedules go...any bigger and I string everything...and as was previously mentioned, if you get too much heat buildup, ( which stainless does well) you'll get cold lap and then have undercutting on the top side...I feel the only position you should really weave anything in is 5G and onlyif it's less than sch. 100...I've seen some ugly welds made on some headers by pipefitter "welders" that was basically three weaves for one cap pass!

probably too late now, but walk the cup, walk the cup and walk the cup. I have different sizes of screen diffusers and cups for different applications. But in my experience even if you are running stringers you should walk the cup. One major advantage is control, another is that your post purge is on the affected area longer giving you better color. Also, I use a rooster tail and turn the torch upside down thus getting the handal out of the way. It may seem weird at first but if you get used to it it will pay off big in the end.