Welding <90 degree joints

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I have a question about welding filet joints. Usually these are at 90 degree angles, and you just run the rod down the corner where the two pieces meet.  Suppose the two pieces are at LESS than 90 degrees, though, say 50-60 degrees?  It would seem that the tighter space has the effect of pushing the rod further away from the actual joint - you can't get as close to it because there's not room. Just for the sake of having an example, let's say two pieces of 1/4" - 5/16" plate that in a normal 90-degree filet you would easily weld with 1/8" 7018AC (AC-only welder).  What, if anything, would you do differently?
Reply:I am by no means the authority on this kind of thing, but in a situation where I'm welding a corner that is smaller than the diameter of the welding rod I gouge top and bottom of the fillet enough to penetrate all the way into the joint, and then back out and fill to the desired weld size. Then just move along, repeating that and holding the puddle back. That's going to be tricky on 1/4" steel and burning a 1/8" rod though. Hope this helps you.
Reply:Grind is one way to do it, I would try and weld from the outside corner of the joint if you can then you have a groove weld instead of a fillet; pr do the first pass with a smaller rod like 1/16 or 3/32 then do a second bead  this is an example of where a infinite amp adjustment is beneficial over a tapped machine.   I really got hooked on running the 1/16 6013 for tight and hard to get to spots.  works very well on thin metals too when you don't have mig available.   A welder with a hot start feature is real nice for running low amps cuz u can set it to start the arc at a higher amperage so it doesn't stickTiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Don't think I can gouge this, Blue.  Good idea, though.Southpaw - I was thinking the same thing. Maybe running a 3/32 6011 for the root, then go back to 1/8 7018AC for the fillers....??Last edited by Ruark; 08-31-2011 at 10:03 AM.
Reply:What you're describing is referred to as a skewed fillet.  Some codes will accommodate for a "z-loss dimension", which accounts for the fact that the weld root is likely to be poor due to the access restriction.  On this basis, you increase the weld size by the z-loss dimension accordingly. Here's a nifty little paper by Duane Miller that offers a nice explanation:http://www.jflf.org/pdfs/papers/design_file102.pdf
Reply:Originally Posted by SupeHere's a nifty little paper by Duane Miller that offers a nice explanation:http://www.jflf.org/pdfs/papers/design_file102.pdf
Reply:That paper is why joints like that are treated like a butt joint and must be done full penetration.  Yes someone can do throat calculations etc. but if it is welded full penetration then there are no arguments.  The inspector sees the joint before welding is started with the one side welded and the root side backgouged out and then does a visual or the thing is X-rayed afterward.  I weld the narrow side then take my grinder and grind out the natural prepared side until I am into sound metal.  No math and no arguments and no hundred dollar weld measuring gauges.