"Undercut" on horizontal bead practice

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3/32 Hobart 7018 - ~90 Amps DCEPFirst time trying this, and on a lot of the beads I was left with what seems like undercut on the bead above it.  Not sure if this is exactly the same as when you have undercut on a joint you're welding.  It doesn't happen when I practice beads in the flat position though, so it perhaps it's something I should be working to avoid.  I was doing a little upward weave where I would pause at the top.  Any tips?  Thanks.
Reply:Quick question... You welded it as shown? Started at the top and welded each bead below the last?If so even though you are moving horizontally, that's technically a overhead weld. Iv'e found if you can't read the puddle yet and know how to manipulate it, that most people have issues doing overhead welds. Overhead is the last of the positions we teach and most don't learn to really read the puddle until they hit vertical.Horizontal beads would be done as if you had that picture flipped 180 deg. You stack each bead on TOP of the one before it, so the previous bead acts like a shelf to help you support your last bead.Other than the undercut, the beads shown don't look bad at all.  There are a couple of small things that might be "off" rod angle might be one of them. If you are slightly long arcing that side of the bead, it will tend to cut in more and not fill as well. 2nd would be if you are doing some sort of motion with the rod, a circle or Z/C shape. You may not be pausing long enough at the top for the puddle to catch up to the arc and fill. Thus the arc melts out the existing material and gravity helps pull it down, but you don't wait long enough for the molten puddle to come up and fill the area you opened up.Not bad, just keep practicing..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Thanks for the response. Yes, it is welded as shown, I hadn't even thought yet about how it should probably be done like you're saying, bottom to top.I'm still really confused about what exactly constitutes a horizontal weld; I seem to see conflicting information.  Could you possibly explain the difference between 2f, 2g, etc?  I thought what I was doing here was 2g, but I'm not sure I really understand the difference.Regarding rod angle - I was kneeling and holding the rod pointed up at roughly 15 or so degrees, and probably using roughly the same for a drag angle.  I would describe my pattern as lowercase cursive u's if that makes any sense.  Like curving forward and up, and holding at the top.  I think you might be right about not holding at the top long enough.  I was experimenting with that by the end, and it seemed to be helping.  Tomorrow I will try bottom to top - building on the shelf.  Should I still curve upward and hold at the top when I do this?Thanks again.
Reply:Maybe these will help some. Note that 2G and 2F for example can describe both plate as well as pipe joints. G usually means a groove joint and F usually means a fillet type joint no matter if you are doing plate or pipe..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Hello Haberdasher, as to the "F"/"G" and numbers: the F indicates a fillet weld, the G indicates a groove weld. The various numbers indicate the position of the weld, ie., 1-flat, 2-horizontal, 3-vertical, and 4-overhead. Where this sometimes gets confusing is with fillet welds. A 1F fillet weld is a T-type fillet that is welded in a troughed position (meaning that the two faces of the weld joint are at 45 degree orientations to the a flat surface). The 2F fillet weld is a T-type fillet that is welded with the bottom plate positioned flat and the upright plate in the vertical or 90 degree position. Hope this makes a little bit of sense. As DSW has stated a horizontal padding weld like you have pictured in your post should "technically" be welded from the bottom of the plate upward providing a "shelf" for each bead to rest on as welding progresses. Looks good and keep up your practicing. Best regards, Allanaevald
Reply:Thanks guys, that totally clears it up.