Looking for MIG feedback

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New here. I've been teaching myself MIG lately, mostly to support the car I run in the 24 Hours of Lemons. Recently I built a cage to install a fuel cell in the car. I'm sure I have a few bad habits already, so I'm looking for comments, criticism, pointers, whatever you want to throw my way. Everything I've done so far is with a Hobart Handler 140 running off a 110 line. 75/25 gas mix with .03 solid wire. Beware, i'm sure i'm about to get a ton of terminology wrong. This is from tonight, making an adapter to bolt onto my engine stand to allow me to mount a Mazda 13B rotary. It's 1/4" angle. This was on voltage "4" (highest), and wire speed of ~53. I realize this is bumping into the limits of what a 110 machine can do. I'm not trying to go for a "stacked" look, I was just pausing ever so slightly on the base before moving again. I should have cleaned the pieces more before welding, but hindsight and all. Attaching a plate to the fuel cell cage to mount the fuel pump on. It's 1/8" plate onto 1" square tube (forget thickness). Settings were 3 for voltage, and ~38 for wire speed. I did a poor job integrating the two welds together on the left, and on the right I started out inconsistent. Finally, a few from my first welds practicing on square tube. I forget the settings I used on these to be honest, but it was either 2 or 3 voltage, and between 30 and 38 wire speed. These were all hit with a wire brush after to clean them up. These are a lot more smooth than my current welds, I think I may be developing some different habits, not sure if they're good or bad. again, I welcome all comments and criticism.
Reply:1/4" is way beyond what a 110v mig can do. 1/8" is the real world practical limit of those machines. The welds may look pretty, but you aren't getting good penetration into the base material with heavy material. That's fine if all you need to do is noncritical stuff like a welding table or yard art, but I'd be very careful about using it to support an engine.The welds on the tube edges are smoother because the tube edges are beveled slightly giving the material a place to go. Those welds don't look bad at all for a beginner.Sheet to tube, you began by partially out running the puddle. Near the end you were doing better, but you needed to tighten up your motions a bit more. I'd like to see at least 2x the number of motions for the same distance forward. That would naturally fill in the saw toothed profile at the toes. The stack of dimes look is fine for tig, but  forcing that pattern on mig can cause issues. Instead of doing big swooping circles as you go, do lots of tiny circles close together and that will take care of some of the issues I see in several of these picts. The beads at the bottom on square tube are much closer to what I'd be looking for from a student. The 2nd to last pict , the center joint looks very nice. The top has some consistency issues, but the bottom 1" is a good one to use as an example of what a nice bead should look like. Biggest thing I note on that section is that you seem to be favoring the right side as the ripples don't look even. It might be an optical illusion because it was wire brushed and the way the camera caught the light, but I typically see that when guys have the gun tilted a bit too much towards one edge of the joint..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:Doesn't look to bad.  Just keep practicing man.  Also if it was me I would step up to a 220 machine.  Good luck!
Reply:DSW, thank you. That's the kind of feedback I was looking for. I don't own my own machine yet. I'm using the machines at a local maker space that I'm a member with. The Hobart 140 is the only one I'm signed off on so far. I played with stick welding for a few minutes the other day, which probably would have been better suited for this, but I wasn't comfortable with it yet. I'm also supposed to get introduced to TIG sometime soon. I know 1/4" is really beyond the scope for a 110 machine, but I figured I'd give it a shot since that's what I have access to. I put a few holes through the overlayed pieces that I'm putting a few bolts through as fail safes when I mount the engine. 13B engines aren't that heavy thankfully.As I mentioned, I wasn't purposely going for the stack of dimes look, that's just what happened. I'll take the feedback and adjust my motions and see what that does for me. I know I need to work on consistency. Part of it is me, a much smaller part of it is the wire feed on this Hobart isn't 100% consistent. You're also right that some welds I wasn't perfectly centered. When I first started I had the mask set way too dark and had issues following the joint line.
Reply:I've never had any feed issues with any of the Hobart machines I've tried. The few times there have been a problem, it's usually operator error or something stupid like the wire passes under itself on the spool..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:This is a machine that gets used by a lot of different people. I can't promise that someone hasn't done bad things to it. But I fully accept that most of the inconsistency is me, not the machine. That said, you can hear the feed motor struggle and slow occasionally. I hadn't thought about the wire being wound under itself, that's a good possibility.
Reply:Try to keep the gun straight, no sharp bends or coils. this can cause feeding problems also.Coil a miggun when done. do not wrap tight around the welder. The corners will put bends in the gun liner. damaging the liner and also causing feeding problems.