Hello bowhunter, with due respect, since you are in a welding program and just starting out you should likely give your instructor(s) the opportunity to answer these questions. If then for whatever reason you feel that you would like to ask for further opinions I believe everyone here would readily help you. You are physically in a welding program, the instructor(s) are there to answer questions for you, show you techniques and give you suggestions on how to better your welding. Give them that opportunity, it is much easier to sit down with a learner and guide them and make suggestions and see the results and give comments for improvements as they are happening, than it is to try to understand a written description over the forum and make understandable suggestions for improvement. Don't get me wrong, it can be done through the forum too, but I am saying go with where you are at right now and then if you still have questions or are looking for answers come here. I do have the utmost respect for all of my collegues in the teaching arena, I also have the greatest respect for the many tradesmen and women who come to the forum and make suggestions and comments for those starting out. There will be times when a method that I prefer doesn't quite work for an individual, that is the time when one of my other partners can likely make the difference and show an alternative that might work better. If I have understood your post incorrectly please forgive me. I really am more than willing to give you suggestions, comments, and other information as are the many other participants of the forum. Best regards, aevald

Hello again bowhunter, the E6010/11 rods are very similar in the manner in which they run and also the appearance of the finished bead. The main difference is in the ability of the E6011 to be operated on both DC+ and AC current as opposed to the E6010 only being suited to DC+ current. The E6011 rod has arc stabilizers that allow it to be run on AC current. Current settings and rod angles can have a great influence on the finished appearance of any welding bead. In general if the current setting is correct for an E6010/11 electrode and the electrode angle is held at 90 degrees as the weld progresses the finished bead may appear rather flat and wide, as the rod angle is decreased(tilted more) in the direction of travel the bead will tend to narrow up and build in height. E6010/11 electrodes are also classified as having a deep, digging arc which gives them advantages for use in conditions where there is a lot of paint, rust, heavy scale, and other surface contaminants. The arc characteristic described as digging makes the arc somewhat violent and causes the roughness in the finished beads made with these two electrodes. The general appearance of the welds made by the other rods that you have listed in your post, are more shallow penetrating, higher strength, smoother arc, and increased build up type rods for the most part(E6013 is not of a higher strength, but it does classify as somewhat of a shallow penetrating electrode with a smooth arc).
     In most instances where I run the E6010/11 electrodes I use a stepping motion to form the bead, strike and hold the rod in one position to form the weld puddle, upon reaching the proper size I step the rod out of the puddle slightly and then step it back into the puddle about 1/16" from it's previous position. If I step out a 1/4" I come back 3/16", if I step out 3/16" I come back 1/8", this positions the finished ripples approximately 1/16" apart from one another. I try not to step the bead more than a 1/4" maximum, that is just a personal determination and definitely not a law or anything. Some of the folks out in industry affectionately refer to this type of motion as "stacking dimes" as it looks as though you have taken a roll of dimes and tipped them over. Depending on a combination of amperage, arc length, and travel speed I can then size the beads appropriately for a given thickness of material. There are also a number of other rod manipulation possibilities, some like to do circles, some like to use a half-crescent motion, and I'm sure there are others. The main reason that I chose to use the motion that I initially described has to do with allowing me to use that same motion regardless of the position of the weld joint. I use it for flat, horizontal, vertical, and overhead, with very little modification. I feel this is less confusing when individuals are learning.
     E6013 in my estimation can be a bit more versatile than any of the other rods you have listed. I have seen it run in the same fashion as I use to run the E6010/11 using the stepping motion, I have also seen it run in a steady weld progression without oscillation, stepping, or whipping, kind of up to the operator. In some instances folks will make vertical welds using an upward weld progression, in others, they may use a downward progression, it is very versatile in this sense. Most of the times that I have used this electrode for welding I use the steady progression and the finished weld deposits will be very smooth and not display  coarse, readily definable ripples, as might be noted when using the E6010/11 electrodes.
     The last two electrodes that you have listed are somewhat different but somewhat the same, E7018 is considered a Low-Hydrogen iron powder electrode, this description means the rod has to be stored in an oven after a fairly short time out of it's original container to prevent moisture pick-up and contamination. It also has iron powder in it's flux which adds to the filler metal that is generated as the electrode is melted. If you run two beads side by side, one being E6010 the other being E7018 and both of them being 1/8" diameter the E7018 electrode will deposit more weld metal. This is due to the addition of the iron powder in the flux coating on that particular rod. You will also notice that the current setting required to run the E7018 is quite a bit greater because of the additional energy required to melt this additional material. In a similar fashion the E7024 has iron powder included in it's flux coating also, yet it has even more so that if you ran a similar test using the 1/8" E7024 and the E7018 the E7024 would lay down a greater amount of weld metal over the E7018. In the same way, the E7024 requires a higher current setting than the E7018. The third digit in the electrode description of these two rods lets you know that the E7018 is an all position rod whereas the E7024 is a flat, horizontal only electrode, if you run much of the E7024 you may not want to run much of it horizontal. I stated that E7024 was similar but different, it isn't classified as a low-hydrogen electrode so it doesn't require storage in a rod oven, that doesn't mean it can be allowed to be overly exposed to moisture, but it is much more tolerant. Both of these electrodes tend to favor being run with fairly tight arc lengths, you can use rod motion with either of these rods, in some situations, but you don't want to long-arc them or whip them. Both of them will give you some problems if the weld joint is tilted downhill any and you are starting at the high end of the weld joint and progressing the weld toward the low end. In cases where the weld joint cannot have the position altered, try to start on the low end and weld towards the high end, in other words I wouldn't suggest running either of these rods downhill, although the E7018 can, in some cases, be made to do this if everything is just so.
     With any of these rods it still boils down to a limited number of things, correct amperage to allow for rod type and diameter, material thickness, and weld position, correct rod angle, both angle in direction of travel as well as rod angle relative to pass # when making multi-pass welds, correct arc length, arc length on the E6010/11 electrodes is much more forgiving and can be varied to aid in controlling penetration by altering arc length, long arc, increase in heat, short arc, decrease heat, arc lengths on the other 3 rods in particular E7018/24 needs to be kept relatively short and not long-arced, bead position on multi-pass welds will be a big factor in the finished smoothness and distribution of weld metal, resulting in straightness and parallelism of the finished weld deposit, travel speed and steadiness of weld progression will determine overall evenness of finished weld and aid in the prevention of cold-lap, wagon-tracking, or other similar conditions. When you are comparing the E6010/11 electrode welds to the E6013/E7018/24 electrodes there will certainly be a considerable difference, the first two will look similar and exhibit a coarser finished weld surface, the final 3 electrode types will exhibit similar type of surface profile and condition and tend to be smoother overall. I got really windy here, but I believe I pretty much covered it. Others will likely chime in now and give their opinions. So as your instructor shared with you, these are opinions, they are meant to be considered, possibly tried out, and then determined for their worth as you see fit. Best regards, aevald