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Was welding up some shelving, 1" .063 square tubing. About 3/4 of the welds had a pinhole like this at the end of the weld. Miller 211, .030 wire. Anybody have any idea as to why?Millermatic 211 Auto-Set
Reply:A lot of times tubing has an oil on it, and in it.Dont pay any attention to meIm just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:I did a quick wipe with acetone, but maybe I didn't take enough care to make sure it was really clean.Millermatic 211 Auto-Set
Reply:that there is a fisheye. Try triggering once or twice after you stop to fill the hole in. Might be a little too hot.
Reply:Might bump your gas up 5.Just a couple welders, big hammers, grinders, and torches.Work will free you.Men in dirty jeans built this country, while men in clean suits have destroyed it. Trump/Carson 2016-2024
Reply:I've had a breeze come in from other end of tube and blow gas out of the weld and do same thing
Reply:TimmyTigs trigger bump works well.Powcon 300st (my favorite)Miller Goldstar 600ssLincoln Idealarc 400/400Miller 12vs2 LN25'sMiller Deltaweld 302Miller Bobcat 250 G EFIMiller Bobcat 225d Plus (Dropped a valve, up soon)Everlast 255ext (ordering soon!)
Reply:Be cognitive of the stand off height of tip/nozzle and your gun angle. Is it possible you were laying your gun angle so low that by the time you got to the inside corner that the corner was blocking some of your gas flow? One thing I learned about trouble shooting/correcting a weld defect is to just correct one thing (whether it is my suggestion or one of the many fine and correct suggestions above) at a time. Example: take the suggestion of not cleaning enough/thoroughly; clean one joint then weld. See what the result were. If it fixed the problem - lesson learned. If it didn't fix the problem, go onto the next suggestion, for instance crank the gas (if you are using gas in the particular welding process you may be using) up 5. If you do 4 or 5 things and the problem goes away; which of the 4 or 5 things fixed it. Bad news is it probably will not be the same thing each time. Good news is the weld defects will minimize (if you are thinking and learning as you weld and not just welding - there is a difference) overtime and you will be able to pin point the issue quicker. Some call this experience. Your doing the right thing by asking questions to fix the issue instead of proclaiming, "Oh well it's good enough, it will hold".Some kind of Big Blue constant current welding machineAnother smaller yet, Blue machine (it's got wire in it)
Reply:I had the same problem with the same welder. I think it was the oil from inside the tubing heating up and vaporizing up through the puddle.
Reply:definitely contamination of the weld be it from the tube or external Make sure everything is clean and turn your gas up a bit might help
Reply:Hello stan921, you have gotten really great answers from everyone who has replied here. You likely read the one that referred to oil/rust inhibitors being predominant on and "in" tube steel. I quoted the "in" because there is often a wicking action that will draw contaminants into the weld pool from the backside of the weld, in particular, when you are running hot. You mentioned cleaning but you didn't really say anything about cleaning the inside of the tubes. You really need to clean both the inside and the outside. Another thing that I "see" is in reference to the "pinhole", When welds are being done on the hot side and you come to the end and release the trigger there can be a delayed action while puddle solidification is taking place. During this time you no longer have shielding gas covering the weld puddle and the weld puddle that was subjected to the atmosphere on the backside of the weld(inside the tube), is now cooling from the outer edges of the puddle to the middle, it is at this point that the "pinhole" can occur and in some instances porosity can accompany this hole. As others have stated: maybe just a bit less heat and/or a slight re-triggering at the end of your welds will assist with the hole. Good luck and best regards, Allanaevald
Reply:It's porosity. |
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发表于 2021-8-31 22:43:43