MIG weld Practice

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I went buy a local metal supply shop here in SF CA (Bayshore Metals) yesterday and picked up some scrap metal from their bin to do some welds on for practice. They let me take four pieces of 1/4 angle iron. I busted out my new Hobart 140 and did some practice beads for a few hours. Used some 25/75 and .030 wire. I know, I know wupty frickin dooo, but it made me happy to get some practice in and see some good results along with finding a metal supply place with friendly people in it. Here is a picture of my favorite MIG weld of the day. It was a but joint that I welded both sides of with maybe a 1/16-2/16" gap. This was the second side (bottom side). I used a cursive "e" motion with my torch. I felt like I got a good even flat looking weld (could have been straighter) with good penetration and not to much splatter. Constructive comments are welcome. Dirty fresh weldCleaned up with a wire cup brushCheers!Cheers from the German!
Reply:My only comment is that MIG needs clean metal. The other thing you'll want to work on, is not leaving the little crater at the end. Just make sure you hold the gun in position at the end when you release the trigger. Perhaps even moving back a short amount as you let off the trigger.Good luck,PapaLincoln Idealarc 250 (circa 1962)Lincoln Weldpak 155 w/Mig KitLincoln Squarewave TIG 175
Reply:Originally Posted by deutschman I felt like I got a good even flat looking weld (could have been straighter) with good penetration and not to much splatter. Constructive comments are welcome.
Reply:Hi you could torch the metal and pre heat it to work with what you have       it will get good welds but ya just cant do it if your pressed for time on lil projects,   as said the step down on thickness.   It will get you in the groove for sure it looks like your control of the weld is pretty good.    was tight on top and got globed out at the bottom... keep it tight all the way and get the penetration.... looks like your there on the control brace your hand well good job on big plate with a lil machine.    you can run bigger wire flux core it will really help it dig but your on the right track....have a good one and good luck my 2 centsoh put a dime in the pics for a scale pic LOL Take care and have fun   OHH your starts stops & tie ins will come later... get the weld done properly and take the good advice from the pros,  as I'm a contractor and repair my stuff and put up lil metal buildings..to let ya know there is better advice from these good folks out hereLast edited by Tony D; 01-19-2012 at 10:49 AM.Lincoln 225 Tombstone,Miller Big 20,Hobart 180,150' Argon,A/D hobart hood 22 Ton Log splitter,79 F350 dump eats 4.75 TONS and still turns cutters,grinders,And a  Hypertherm POWERMAX 30
Reply:Originally Posted by DSWNot bad as far as looks. As said mig like clean metal. A wire brush will not cut it. You really need to use a grinding wheel or a flap disk to remove rust and scale.Understand the 1/4" is way to thick for that machine to make decent welds. 1/8" is the maximum thickness that little machine will do under real world circumstances. The bead you made has no real penetration into the base material despite how "nice" it looks. If you didn't have the slight "bevel" from where the rolled edges met, your bead would look a lot worse because of how tall and cold it would be.There are issues using material well beyond the rated thickness for practice. First you won't really learn what a good welds looks like. There more to a weld than a "stack of dimes". You need to look at the toes of the weld to make sure they wetted in well to the base material and the bead isn't just sitting on the surface. A bevel on heavy material will help disguise cold lap and poor penetration and make it harder to learn what a good weld looks like.Second, the thicker material will not teach you anything about heat control. With small machines, you will be limited to thin materials. Burn thru will be a bigger issue with materials within the ability of this machine. It takes no skill to simply squirt metal onto heavy plate and make a cold weld. It's a lot harder to do a decent job on say 1/16" where the range between a cold weld and blowing holes in the material is fairly narrow. Move to thinner metal, and the range gets even narrower and heat control gets even more important.