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After stick welding for years, I finally bought myself a Lincoln HD3200 Mig welder. I have managed to get a few good stringers every once and a while, however, some of them are pitted. What causes that?
Reply:do you mean pitted as in little holes in the welds , thats because of no gas coverage , this could be wind if your outside or somewhere open , it could also be from the wrong gun angle , are you pushing or pulling the gun ?
Reply:How clean is the metal? Does it have lots of rust or oil?Millermatic Passport PlusMillermatic 200Millermatic 350P with PythonXMT 304 /w S-64 feeder and 12RCDynasty 300 DXVictor O/APremier Power Welder for my trail junk.
Reply:Could be lack of gas on the weld (wrong angle, low pressure)Or... Boiling out impurities in the metal (dirty steel)Or... Too fast travel/wire speed. Try slowing down the wire speed and slow travel speed. This gives the molten pool more time to penetrate, fuse, and boil out impurities.Or... Moisture. You quench your piece and get some water in the joint that doesn't evaporate you will get porosity. If you are quenching, heat with a torch for about 20 seconds until too hot to touch and try again.Or... Wrong gas mixtureAnd if all the above checks out you probably have bad wire. If your spool of wire is old or if you got a bad batch you will get porosity. Try a different spool if nothing else works.
Reply:I'm sorry, I forgot to mention that I was using flux core wire and no gas. I will try that later on. The metal that I was using was rusty, but I cleaned it up the best that I could with a wire wheel on a angle grinder. How clean does it have to be? Like down to the shiny metal? I did notice also, that if I held the gun at too much of an angle it seemed to get worse.
Reply:With flux core the metal can be a little dirty, but cleaner is always better. If you can get it shiny, then that is less chance of a bad weld and is also easier to weld on. Less spatter for one.Angle and speed of travel are probably the reason. First of all, if you are doing a 45 or other angled root then aim directly at the root.Try at first to weld with the tip of the gun aimed at a 90 degree angle to the direction of travel. Then try again with the handle tilted towards your direction of travel by a few degrees at a time until you find a good angle. (wire pushing back in the direction of where it came from) Flux core gets better penetration when you drag the wire slightly instead of push it. So it's a good habit to learn dragging but pushing is also good to get the feel of for lighter guage material. Also try slowing down and messing with the wire speed and heat. It should make a nice sizzle sound like freshly cooking spam if setup right. If it is crackling and popping your settings are off.
Reply:211 has a nice hiss to it when it is running right. To much voltage is a killer in T-11 wire.Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:Do you have negative electrode?DavidReal world weldin. When I grow up I want to be a tig weldor.
Reply:This is a pretty good site from Miller showing some weld pictures and problems.http://www.millerwelds.com/education...tips/MIG_tips/ |
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发表于 2021-9-1 00:09:24