Rate My Weld Please

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I have been working on my MIG welding and I would like some input from others to see what I can improve on.The first photo is a vertical down on 1/8" mild steel.  I increased the heat and wire speed to get better penetration going vertical down.The second is a horizontal fillet on 3/16" mild steel.  I know my travel speed was not consistent, but the weld seems to be pretty good.Thanks in advance!Mike  Attached Images
Reply:just from you photo I'd suspect the vertical of lacking penetration.  What would interesting for you to do to prove me wrong would be for you to do a destructive test on it.If you hammered or crimped the two sides together we could see how your weld worked.  I have found that we learn a lot more from our failures in all aspects of life than we do in our successes.So the best test of a weld is a destructive one when we're learning.  And it's best if that test is done as soon after the weld is completed as is practical.  That way if there is a failure making the weld is fresh in our minds.  And we can put together what happened and why.life is good
Reply:Pretty good looking for verticle down. I never feel good about downhill for my low talent level. I always feel like I'm trying to outrun the puddle rather than focussing on burning into the base metal.  What's the back side look like?
Reply:When I get a chance I will run down to my shop and put the test weld in my 20 ton press.I only welded one side, so I will lay it in the press exposing the non-welded side to all the pressure and see if it breaks.Mike
Reply:Sandy,  I will get a photo of the back side before I crush it in my shop press.Mike
Reply:The vertical down look good try a vertical up weave.the flat is rounded did you use drag technique try a push angle
Reply:I used the drag for the flat weld.I have tried various verticle up welds but I usually end up with way too much weld or burn through.  I cannot seem to figure it out.I purchased a MIG welding video and they say that for MIG verticle down is the way to go, you just need to turn up the heat to get the penetration for the faster downward speeds.  The verticle down weld appears to have good bite on the sides.Mike
Reply:I took some photos of the back of the vertical down weld before I crushed it in the press.  I have also included photos of the crushed parts which passed the destructive test.I guess turning up the heat for the vertical down worked...The first two photos are of the back and bottom of the vertical down weld and the others are the destructive tests.Mike Attached ImagesLast edited by malich; 03-23-2005 at 11:23 AM.
Reply:Well malich, looks like you passed your test!!! Looking at the backside/butt view of your vert-up T joint you can see yourself where it started maybe just a little cold and the heat grew as you progressed down. Verticle up tends to minimize that a little more, evens it out so to speak. But as far as vert up or down it seems like everyone learns what works for them. As long as penetration or good fusion is your main focus, and it seems like that it is for you, you will always be doing what makes the best weld, not just the easiest or prettiest. Hey in real applications, if there is any question in your mind, you can always grind one out and do a visual. I've done that rather than worry over a failure. Doin good. Keep it up.
Reply:I notice that on your joints you tacked the back side.  You might try not tacking the back side.  That way the root of the weld should open up and you can inspect which side fails or if the failure is through the weld which is unlikely.  The fracture will give you insight into the weld bead and its fusion.  A common shop test is to set up a tee joint, weld two inches then snap it open with a hammer in a vise or whatever is available.  The weld passes is there is no porosity and the fusion is good on both sides.
Reply:Sandy,Any suggestions in wire feed / voltage for doing vertical up welds?  I seem to get too much weld or burn through vertical up.  Also it can be hard to see the weld puddle.Also should I use the push or drag for vertical up?Thanks,Mike
Reply:Lotechman,How should I snap this weld open?  I may be not understanding you correctly.  If the weld is good it will hold.  The test welds I made were a 2" weld.Thanks,Mike
Reply:Test weld three has a tack on the back side dead center as well as tacks at each end that close the ends.  When you bent the sample all the stress was on those three tacks ( good tacks by the way)  .  There was no tension stress on the root on your "other side" weld.  The bending has stretched the tacks and they act as a fulcrum putting compression on the large fillet.   Do the test again but with no tacks on the ends or free side.  When the weld fractures you will be able to inspect the fracture line for porosity or inclusions.  If you failed to fuse into either side of the fillet weld the fracture will find that location.  Making a big weld that won't fail when tested with a hammer tells you very little.   If you look a a car or truck frame you will see many ugly welds that are not done well at all.  The reason that we don't have vehicles falling apart all over the road is that there is more than enough weld to do the job regardless of quality.
Reply:The reason for the destructive test of a weld is to see what actually happened.  It's not so much a test to see if the weld is good but where it's good and where there's room for improvement.  The only real way for the casual weldor to actually see what happened is to destroy the weld and then look to see where it fused and where it didn't.Let's say you break the back of the weld.  It pulls from both sides but at different ends of the weld.  You know that you moved the puddle more to one side than the other as you welded.  That tells you to concentrate on keeping the puddle even on both sides and not to let your mind wander to that truck you want almost as much as you want to date that girl with the friendly eyes.If the weld breaks down the middle of the weld then you know your puddle was carried even.  Depending upon the thickness of the weld in comparison to the material welded you can judge whether you need to slow down a little or maybe cut your amperage back, maybe a combination.Everyone wants to believe it's about the control of the puddle.  They want to think seeing the arc and stacking each ridge makes them a weldor.  That isn't the way it is.  Laying a pass is not unlike a using a cutting torch or plasma to lay down a cut.Machines do it best.  And the reason  machines do it best is because it's all about speed and heat.  Automatic welding is about consistant speed at the right amperage.  For the individual to compete with that kind of weld they have to do the same thing the machine is doing.  Concentrating on speed and heat.Watching the puddle is not the end all for doing a good weld.  What you're hearing has a large amount of input.  And probably as important as both of those is keeping the travel speed consistant once you're rolling.As for the difficulty in welding vertical versus welding flat or downhill one has to keep in mind the exact same thing is happening in all three circumstances.  The only difference is the concentration and speed control of the weldor.With the vertical things are happening faster and so the weldor can't sit back and watch the puddle because the puddle is behind where the action is.  The puddle is falling so the concentration needs to be ahead of the puddle.  The results will be the same.  It's just the attention of the weldor needs to be in a different aspect of what's happening.Think of it like trying to pull a center line to center line measurement across two parallel pieces of pipe.  You can get the measurement by going center to center.  But if that isn't practical you can get the same measurement by pulling an inside of one pipe to the outside of the other or vice versa.  You're able to come up with the same measurement.  It's just that your attention is in a different place.  The same is true of vertical welding up versus flat.life is good
Reply:Malich, What lotech and harv are saying is that when playing and testing you want that weld to fail somewhere somehow if at all possible. Only way to tell why the manuals tell you what not to do. Here's a quick one I did a bit ago. You can see I beat it as flat as I could beat it without being foolish. This one is vertical up. I did two, both came out the nearly same except the first started cracking at the start. Starts are generally cold with mig. That was good because it reminds me once again about cold laps being so pretty. I forget that a lot. Now here's my bailout clauses. 1) I sorta cheated, I had 035 on and didn't want to change back.  You are probably using 030.. 2) I was using the auto focus on the camera and three out of five of the pictures came out fuzzy. Two that were fuzzy just happened to be the beads and one was the cracking. You do believe that don't you??? (Chuckle) Anyway here they are. The one fuzzy one shows the bead would be very oooogly if it was clear so I'm glad it didn't turn out. Attached Images
Reply:Originally Posted by malichSandy,Any suggestions in wire feed / voltage for doing vertical up welds?  I seem to get too much weld or burn through vertical up.  Also it can be hard to see the weld puddle.Also should I use the push or drag for vertical up?Thanks,Mike
Reply:Sandy,When you do vetrtical up do you use a push or drag angle?  And any special movments or just striaght up?Also do you find a need to lower the wire speed and heat for the vertical up?Thanks!Mikep.s. opps.  I just saw you other post to my above questions.  Thanks again!