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Hey guys.I'm working with a group at my University to build a car. I'm the main person doing the welding, and we're using TIG for practically all of the car.The frame consists of mild steel from 0.045" to 0.095" thick. I am coming across a huge problem with dirty welds though. On almost all of the joints, there's a nasty issue of splattering and spluttering of the puddle. It's practically unweldable for how bad it is. It honestly looks like I'm trying to weld with the gas off.We're making sure the tubing is clean. Every joint is ground to clean steel and the insides are filed away and acetoned if there is oil. I'm using 2% thoriated tungsten and pure argon around 14-15 cfh, slightly more if I use a gas lens. If I weld on a flat surface they are usually fine, so I think the gas coverage is alright, but once it gets to actual joints it's rare to get one that welds decent. I'm double checking the torch and cord to make sure nothing is snagged or pinched. Even with a new gas lens the issue is still there.Any help here? This is incredibly frustrating and I have no idea what to do. I tried someones elses tip to use a small amount of stainless filler, which he said should "clean" up the puddle and fix the issues, but so far even that isn't working well.Thanks all.-Don N.Last edited by Don Nguyen; 12-03-2013 at 04:23 PM.
Reply:Does it happen immediately when welding the joints or does it start off OK then go bad?http://all-a-cart.comWelding Cart Kits and accessories
Reply:It depends on the joint. On some of them they start alright and then get to a section and all of a sudden it splatters all over the place and shows that ugly brown oxidation around the weld area.On some other joints, it starts right when I start up the arc.
Reply:Are the joints properly vented to prevent out-gassing?http://all-a-cart.comWelding Cart Kits and accessories
Reply:Originally Posted by ZTFabAre the joints properly vented to prevent out-gassing?
Reply:Originally Posted by ZTFabAre the joints properly vented to prevent out-gassing?
Reply:Originally Posted by Don NguyenHey guys......The frame consists of mild steel from 0.045" to 0.095" thick. I am coming across a huge problem with dirty welds though. On almost all of the joints, there's a nasty issue of splattering and spluttering of the puddle. It's practically unweldable for how bad it is. It honestly looks like I'm trying to weld with the gas off.We're making sure the tubing is clean. Every joint is ground to clean steel and the insides are filed away and acetoned if there is oil. Thanks all.-Don N.
Reply:have you tried welding some regular flat bar or something else? 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:"I'm using 2% thoriated tungsten and pure argon around 14-15 cfh, slightly MORE if I use a gas lens."Are you actually turning the gas UP when you change to a gas lens?You need less gas with a lens, not more. It's possible you're creating a Venturi effect from too much gas flow when you're changing angles, but some unseen contamination seems more likely.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:You have some kind of contamination in your metal. I would try purging it with argon. Carbon steel tube that thin is pretty hard to weld, a purge will help a lot.Last edited by TimmyTIG; 12-04-2013 at 05:52 AM.
Reply:You've checked the lead for kinks/pinches, have you checked it for leaks? Does your torch have a gas valve on it?
Reply:Originally Posted by dave powelsonIOW--the entire inside of the tubes was not blown out, then wet swabbed and blown out again; to remove any residual oil, saw lube, etc.----which will run down or to the weld in progress.It doesn't hurt to actually LOOK inside the tubes before and after swabbing, either.
Reply:Change out the gas lens or put the standard one back in to see it you get an improvement. Sometimes the screen gets blocked on one side. Peeling a screen off can help.Also check to see if your collet is crushed or twisted. That can block gas flow. At times the gas lens seat where the collet pinches the tungsten starts pushing thru to the front and your backcap can cut off the gas port also blocking flow.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Had a hose issue with a machine last night. Hose had a hole in it where someone dropped a piece of hot metal or slag on it and it melted thru in one spot. I was getting some gas flow, but not enough. Took me a bit to track down why the student couldn't get decent welds.A damaged torch, missing o-ring, loose or incorrect torch parts etc might also be the problem..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I Agree to clean out the insides of the tubes with a rag or swab on the wire fed threw the tube from one end to the other.Are your joints tight or big gaps?
Reply:Originally Posted by Drf255Are you actually turning the gas UP when you change to a gas lens?You need less gas with a lens, not more. .
Reply:Originally Posted by pepiNot to hijack the thread, only a quick question. If the flow is 15 cfm without a gas lens, what would be an approximate setting of the flow using a gas lens?Never thought about a possible difference of the flow rate with or without a gas lens. Yes, I am boot is the reason for the interest and question.Thanks in advance.
Reply:Originally Posted by ZTFabDoes it happen immediately when welding the joints or does it start off OK then go bad?
Reply:Bad gas? Maybe try another tankWhat are your settings on the tig machine?
Reply:Tubing clusters seem to form a venturi effect and are prone to pulling atmospheric air into the envelope. I will ususally try to keep the shielding gas speed as low as possible by using the largest cup and lowest flow rate I can get away with. I am assuming obvious things like breezes in the shop have been eliminated?
Reply:Originally Posted by shovelonOr does it start off bad, and get ok?
Reply:Originally Posted by Don NguyenThis is never the case - if it starts bad it will end bad. I can weld in one section of a joint and it will be completely OK, and then skip to a section 1" away, same position, and it will be unweldable.
Reply:Show some pictures of the welds on the car, and prep up some scrap and make some welds and show pictures of them as well bud. That will definitely help break this all down for ya! We'll get this sorted out in short order. I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:Originally Posted by makoman1860Tubing clusters seem to form a venturi effect and are prone to pulling atmospheric air into the envelope. I will ususally try to keep the shielding gas speed as low as possible by using the largest cup and lowest flow rate I can get away with. I am assuming obvious things like breezes in the shop have been eliminated?
Reply:Originally Posted by MinnesotaDaveI've never welded tubing clusters - but I saw a video where Jody put tin foil behind a cluster to trap argon.Around minute 9:00Originally Posted by zapsterLet's try to keep his vids to a minimum...He has his own site....zap!
Reply:Well I guess now we can't reference Miller or Lincoln, they have their own sites too. Dont pay any attention to meIm just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Originally Posted by shovelon Vertical and out of position benefits with smoother gas flow. You are a boot?
Reply:Originally Posted by MinnesotaDaveThat's a weird request, must have been tongue-in-cheek since he has some of the best instructional vids out there.I'm not affiliated, but he has sure helped me out by having them.
Reply:I really appreciate all your time everyone.I'll try to get some time and do some more welds and take pictures, but it could take a while from a busy schedule.
Reply:Originally Posted by pepiThat I knew about the purpose of the gas lens, never heard of dialing back on the cfm before is all. Any quality brand of gas lens one should be on the look out for? Got some from Ebay and was not all that jazzed with them. Went back to the standard cup, figure I'll try again in the near future. TIG is a whole new ball game here, MIG is so much more forgiving, I like the hell out of it just not where I want to be yet. Reading this forum, the best I have found for everything welding. Many things seem to pop into some of these discussions, unintended knowledge ... LOLThanks for all the knowledge you inject thru out this site.
Reply:Sounds like air current, wind, is blowing your shield argon away or you have galvanized tube.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:Hahahahahaha Terry you make me nuts, Peeling a screen...LMAO talk about needing a bigger allowance...As far as the welding issue I don't know what the total problem is but I did pick up on the statement "Brown Oxidation" That usually happens when you dip the tungsten, If thats the case and your NOT dressing it right then.....The rest of the weld will be compromised......Brown soot happens...Check the tungsten Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Originally Posted by B_CHahahahahaha Terry you make me nuts, Peeling a screen...LMAO talk about needing a bigger allowance...As far as the welding issue I don't know what the total problem is but I did pick up on the statement "Brown Oxidation" That usually happens when you dip the tungsten, If thats the case and your NOT dressing it right then.....The rest of the weld will be compromised......Brown soot happens...Check the tungsten
Reply:I take out screens as they get boogered up. I believe there is like 5 screens in my weldcraft lenses. I'll pull out two screens before replacing the lense.
Reply:Originally Posted by shovelonI need a bigger allowance? Ok yes, I do. I do however rebuild my big ones.
Reply:Just giving you guys a bad time I have removed the screens also trying to keep from installing a new part........ Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock |
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发表于 2021-8-31 22:39:03