Third session MIG welding

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Well, here's some pics from my third MIG session.For reference, I'm using a Lincoln Electric SP-125 Plus set at H-7, 0.024" ER70S-6 wire, C-25 at ~20-25 cfh and welding on 2mm mild steel.Based on the helpful feedback and suggestions in my first thread and second thread, I turned up the heat, slowed down, held the gun more vertically and tried to focus on the weld puddle. I followed soapstone lines I'd ruled in on the piece and did shorter welds (~6" or so), stopping at the end to view the result and trying to make adjustments for the next one.Wide view of the welds. I started on the left and progressed toward the right.Close-up 1:Close-up 2:Backside of the plate:As before, any feedback is welcomed and appreciated (not to mention read and re-read by yours truly  ).A couple of questions:1. I've read that the piece should be clean in order to acheive the best weld. What's the best way to remove the mill scale? Wire wheel on an angle grinder?2. The last poster on the second thread mentions that a setting of 9 on my AD helmet isn't good. I was going with a lower setting based on advice from another poster in my first thread. Naturally, my eyes being important to me , that makes me a little uncomfortable. What is the truth on this? At the lower settings I can actually see what's going on, but I don't want to jeopardize my sight in doing so. Attached ImagesBefore you criticize someone, walk a mile in their shoes. That way, when you criticize them, you're a mile away. And you have their shoes.Roland
Reply:I hadn't realized I was limited in the # of pics per post. Here's part 2 of the third session.I wanted to see weld penetration, so I did some welds along the long axis of a narrow bar and cut across the welds with my Makita 2412DB. I don't know that this was the right tool to cut with, because I can't see any detail as to weld penetration (but then, this is the first time I've ever tried this so what the heck do I know?  ).If this wasn't the best way to do try and look at the weld, please let me know what I should do instead. If the pics don't offer the detail necessary, let me know that too and I can reshoot them.Before you criticize someone, walk a mile in their shoes. That way, when you criticize them, you're a mile away. And you have their shoes.Roland
Reply:Looks like it's time to start working on some joints.  Keep it up!
Reply:And this is part 3 of 3. I tried joining two pieces at right angles (this is a fillet, right?) Settings were as mentioned above, albeit the stock was 3mm thick.This was unexpectedly difficult. The weld bead ended up not going where I'd expected it to go at all. I'm also going to have to get me some of those magnetic welding clamps (the ones that look like an arrow). I used 3 round rare earth magnets set on edge (all I had that I was willing to expose to the tender mercies of the welding shower...) and it was a bit of a PITA to get them to hold the pieces square.Here I did some vertical welds just to try. I was a touch surprised the weld puddle doesn't run like its liquidity would lead you to expect it would.A couple of questions:1. Do I need to grind a bevel in here, or is this sort of fit-up something that comes after I'm actually able to fit & hit the corner with the bead?2. What's the best way to get a view of what's going on? I was going from left to right, looking down on the weld. I was fairly sure I had the gun at 45* but given the outcome, I think I was probably off on that.Before you criticize someone, walk a mile in their shoes. That way, when you criticize them, you're a mile away. And you have their shoes.Roland
Reply:For the fillet and Verticle up use a slight ollsilation(sp) to keep the puddle moving and wetting into the base metal. And on the fillet pause for second(not really a full second) at the top and drop the arc down to the base metal and back up. Just because gravity always wins and staying on the high side will help you out. I think with a little movment everything will wet in a little better at the edges of your stringers.
Reply:Keep up the hard work, you're getting it.By session #10 you may graduate to using a dime in the photo instead a penny.
Reply:To answer your last questions first.  For the fillet, you need more heat.  The pieces don't have to be exactly 90 for a test weld.  Magnets to me are a pain in the azz.  They can make your arc go off course (arc blow) and always collect chips and stuff.  Just hold the pieces and tack them on the end at the T.    OR tack it in the center and feel it pull the piece over as it cools.  If you tack the end, you can bend it a little to get it square.  Too much and the tack should break.  That is what a tack is, a temporary weld.As for which direction you weld so you can see, what ever works for you.  Same thing with the helmet.  Adjust it so you can see the puddle.As far as weaving, it works.  If you think "weld the two pieces together" instead of run a bead, it will work better.  Go from one plate to the other pausing at each side.  Watch the puddle.  When it is big enough, move on.The metal will follow the heat, that is how you can weld up hill.   A groove or just a bead is harder to run up hill than a fillet.   While you are pausing on one plate, the other one is cooling.  You can practice weave beads on flat too.  They should be 5X the wire width.    Go 2 wire widths from the center as you weave back and forth.I have had an SP100 for about 20 years.  Still use it.3mm = 1/8" give or take a little.  Or .120", or 120 Amps as a guide.  Isn't there a chart inside the door?If it is plugged into a good ciruit, put it on H10.  Learn what it has and its limitations.Buy a short piece of exhaust pipe 18"?  cut slits almost all the way through it and weld it back together.  You need to wire wheel the coating off the pipe before you weld it.   I weld a lot of exhaust on C3.DavidLast edited by David R; 01-10-2008 at 06:53 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Roland, I'm glad to see that you are concerned about your vision. As an old farm boss I worked for a long time ago liked to point out," you're using the last two eyes you will ever have so protect them". Personally I wouldn't use any of the cheap auto hoods. If I were still welding all time I would buy one of the high dollar Jacksons or a Lincoln which I believe is made by Jackson. People's eyes are different and some need a darker shade of lens than others. There are guidelines but you will have to make you own decision. Personally I use the darkest I can see the puddle and a small area around it clearly with.Lincoln Electric published an article years ago about eye protection that was very interesting. In it they pointed out that infrared rays are the ones that destroy the rod and cones in your eyes and you never feel a thing. I guess that is why I've seen so many welders that didn't use cutting goggles that couldn't see a damed thing anymore.
Reply:Originally Posted by Roland CoppensAnd this is part 3 of 3. I tried joining two pieces at right angles (this is a fillet, right?) Settings were as mentioned above, albeit the stock was 3mm thick.This was unexpectedly difficult. The weld bead ended up not going where I'd expected it to go at all. I'm also going to have to get me some of those magnetic welding clamps (the ones that look like an arrow). I used 3 round rare earth magnets set on edge (all I had that I was willing to expose to the tender mercies of the welding shower...) and it was a bit of a PITA to get them to hold the pieces square.A couple of questions:1. Do I need to grind a bevel in here, or is this sort of fit-up something that comes after I'm actually able to fit & hit the corner with the bead?2. What's the best way to get a view of what's going on? I was going from left to right, looking down on the weld. I was fairly sure I had the gun at 45* but given the outcome, I think I was probably off on that.
Reply:Edited:  I took too long replying, info already covered by David and Pulser.Last edited by DesertRider33; 01-10-2008 at 07:52 PM.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op