Hello atramsdell, I'm a little bit late to post on this one, yet I believe I can possibly give you some additional food for thought. All of the other folks who've replied have given you a great number of different and very applicable options and approaches to better your overhead welding skills. Since welding isn't one size fits all, you now have a host of different approaches to consider.... that's a good thing. I'd like to add a few items as well. Surface tension comes into play a lot in the overhead welding position, especially when we're talking about E7018 electrodes. If you possibly aren't familiar with the term I'll give you an example of how I interpret this phenomenon: a drop of water on a glass table top, you put your finger into it and it adheres to the end of your finger to a certain degree as long as you don't raise your finger back up too far or quickly and it also follows your finger around the surface of the glass to some degree if you don't move it too quickly. If you do raise up too far it will disconnect and splash back onto the glass surface, a weld puddle can do something similar. With the overhead bead, varying the arc length too much or too quickly or changing the travel speed in a similar fashion can cause the arc to "disconnect" and the puddle to slide rearward towards the already deposited weld metal and since we're talking overhead here this will likely result in a "sag", at this point the weld will reconstitute itself but in a slightly narrower and shallower form. If an individual continues to weld without taking care of the arc length/travel speed issues the resulting weld deposits will be very uneven and have many highs and lows. If you are filling a groove this can cause extreme frustration when you try to speedup/slowdown to compensate for the uneveness while filling the rest of the groove/fillet. I often times find additional issues with "arc blow" and it's effect on the weld puddle in the overhead position. If you are running the bead across the plate/groove/joint and you start to see the arc "blowing" and possibly exiting out the rear of the rod along with irregularly sized spatter as you progress forward, that may be an indicator of this condition. Besides the general grounding approach changes and other things to minimize this condition I will generally start with a slight backhand(dragging) angle and then progress to a forehand(push) angle to help to deal with this condition. Another item I try to pay attention to is the "Lay" of the joint, whenever possible I try to start my weld on the low end of the joint and progress towards the higher end, this is certainly not always possible so in many cases you just have to deal with a downward slope, if you do have the option, then I suggest moving from low to high. The reason for this has to do with the flux/slag that is a part of the E7018 rods and many others. If it is allowed to get out in front of the arc it will cause the arc to sputter, the toes of the weld deposit to form in-correctly, and very likely allow entrapment of slag in many cases. When being forced to weld in a somewhat downward progression an increased backhand angle along with possibly increasing the amperage may help to minimize the slag entrapment issues and bead formation problems. An additional comment that I have deals with arc length, from my personal perspective there is going to be a "sweet spot" that will allow the arc to spread correctly and form the bead optimally. Too short of an arc length and it either sticks or litterally stirs the weld pool and makes for an uneven weld deposit. Too long of an arc length and you possibly suffer porosity in the weld bead or such a mis-directed arc, as it dances around on the end of the rod, that it makes an even weld bead next to impossible. When you get the arc length right you will generally end up with a smooth/even bead that goes where you put it and has very nicely tied in toes and the correct width to height ratio. Others mentioned heat settings, I generally agree that I use a setting similar to that required by welding in the flat position. Having said that I would like to throw another consideration out there for you to think about. When the heat is too low it won't matter what sort of rod angle, arc length, or to some degree travel speed you are using, your bead will end up being humped up, possibly narrow, and not making the profile you are looking for. Some of this can be due to a lack of energy that prevents the bead from spreading correctly. Too much heat and the bead is so hot that it will remain fluid too long and migrate towards it's center creating a sag in the middle of the bead and possibly exhibiting undercut along the edges as well. When you get the heat right, along with the other considerations, you will be able to run a bead that isn't all that different from one run in the flat position. One final tidbit here, material condition will have a lot to do with the success of your welding efforts. If you are welding on materials that have a lot of rust, millscale, oil, grease, dirt, etc., all of these items can have a detrimental effect on a weld. Even though there are plenty of times when we might not be allowed to properly prepare our welds, if you have the option to do so it will do you worlds of good to take that additional bit of time. Good luck on your practice and best regards, Allan
Welding is not a spectator sport; you gotta get all the way in.
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