For 6013 vert-up T-fillet welds, finding that can only get fillet-corner ("root") penetration if the rod is sloped slightly downwards - which is not in agreement with common procedure, is it?
What should I do to correct the situation?
Using 6013 rods - that's immutable - it's a UK thing. (7018 - not the same problem - fillet corner fusion easily achieved).
Running DCEN - that's a convention in the college I attend.
Technique is 2.5mm dia (3/32nds of inch) 6013 root, 3.2mm dia (1/8th inch) 6013 weaved single-run cap - all at 80A, DCEN
I get fillet corner fusion when the rod is tipped at a down-angle of about 5deg to 10deg. So am burning a cavity under the rod tip and the metal and slag are running clear, enabling unimpeded bead formation under the tilted-up lower edge of the welding rod. Don't easily get a flat root-bead using these conditions, but fusion and penetration is sound.
Can't get fillet-corner root fusion with recommended condition of 5deg to 15deg of slope-upwards. Get a lack-of-fusion defect reaching out from the fillet corner by about a millimetre.
With up-angle, can't make arc land ahead of melt-pool, burning into the fillet corner. With capping run, have no problem running with
5deg to 15deg of up-angle, arcing onto the "black" plate-metal back-face and root-bead. Only root run a problem
Have sketched and scanned my welding conditions and put them to my website at
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Can stay with convention for the capping run, getting a good finished fillet bead.
6013 rods belong to the group referred to as 'fast follow', the puddle will follow the arc in a longer thinner puddle when travel speed is high. They are a low penetration rod and most can be used with either polarity, but with dcsp/dcen prefered as this will also give less penetration and is handy for welding thin sheet metal. They can be used up or downhill and with whiping or straight forward progression. They are similar to 6012. 6013 (and 7014) are good for limited input AC power transformer buzz box welders and are popular with hobyists and farmers for this reason, (many buzz boxes will cause 6011 & 7018 to be very sticky and hard/impossible to strike an arc). 6013 is seldom used in industrial work but IMHO does have a place in misc fab and repair whenever fast follow and low penetration is desired. I carry a small amount on my rig but almost never use them. The very small
1/16" & 5/64" rods will allow a large DC machine to do very light work that would normally be better done with a small MIG, and 3/32" & 1/8" are handy for poor fitups and for welding thin steel sheets, particularly downhill as this leaves your heat behind the arc and will limit distortion and burn-through. IMHO they are a specialty rod and have no place in a school or training environment or in serious work, IMHO 6010/11 (fast freeze, deep penetration, dcrp/dcep) should be used in preference whenever possible.
DCRP/DCEP will give deeper penetration and is preferred for almost all SMAW stick welding.
Published amp ranges are-
3/32" vertical 30-70A
1/8" vertical 70-120A
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Your descriptions are excellent but, in writing it is difficult to describe and even harder to analyze welding technique. Like comedy, in welding timing is everything, it takes a lot of practice to understand and develop the visual clues. A good demo is worth thousands of words.
Many of us have do not like side to side weaves in general, but (with
10/11/12/13 rods) prefer straight ahead whipping to vary drooping volt/amp curve and allow the puddle to freeze, but some can just go in and out. For large non-critical maximum fill, single pass welds with lo-hi (7018 etc), many of us prefer a triangular weave (with dig for penetration and fusion at the top point and a pause at the lower side points, just long enough to fill and prevent undercut) and just drag high powder rods (like 14/24/28 'jet') Critical or high strength welds should not use a weave wider than 1.5-2x rod dia.
You do not specify the thickness of the base metal you are working with, but I suspect that it is too thick to keep hot using 3/32" and wonder why not use 1/8" for the first pass. If this is done as a training exercise I suspect that you need more heat (and dcrp/dcep) with both sizes of rod. IMHO, the first pass of a T fillet is not really a 'root pass' unless you are making a full penetration weld in heavy plate using a V or J bevel and a root gap.
Really really appreciate your detailed response. It tells me things I suspected, said from an independent viewpoint far from local customs.
The important detail I missed out - plate thickness is 6mm (1/4inch).
Regarding using 6013's in the UK - it's almost a religious orthodoxy here. It would be like going to Vatican City to see the Pope, explaining to him that population explosion is causing human misery in resource-exhausted places like the Philippines and expecting him to therefore condone a new policy that birth-control is appropriate.
One "exactly correct for purpose" use for 6013's you don't mention - when you have to guarantee the weld will rip before the plate metal. Useful for things like height restriction barriers to car-parks, where you weld in an angle-iron insert at the corner between the upright and the baseplate, so that another vehicle impact will progressively rip the weld and cause the barrier to gracefully collapse again.
If I have to use 6013 "all the way" on a vert-up T-fillet: - DCEP - entire fillet weld in one go - some variant of a triangular weave
The properties of 6013 are so low that you aren't throwing any away making one big run, are you?
Had to let my welding instructor off eating his hat when I showed I could use these conditions with 2.5mm dia rods at 75A on 6mm plate and get fillet corner fusion.
Not allowed to use 3.2dia (1/8th dia) rods for the root run at the college.
DCEP vs. DCEN. It is conventionally stated that DCEP gives more pen. I know from experience doing vertical welds on plate metal that DCEP gives more fusion / penetration and DCEN is good for wide-gap filling where want more metal and less heat. Swapping polarity is a means of control which works for me.
Something I have learned the hard way here in the UK is that recommending using other than 6013's will lead to some extreme resentment at some point in the near future and probably cost you your job. Someone has strongly recommended "stoving electrodes" (6010's/6011's) on one particular site job with the Co. I am working for now, which would have the huge advantages he describes - and I've steered well clear - been there before...
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