|
|
I'm new at tig and I've mostly been practicing on aluminum. I got some mild steel stock and decided to run a bunch of beads and some lap joints (DC of course), but I started having some weird issues. I was getting lots of sparks and priority even when not using filler and just moving the puddle around. I spent the last two days trying to figure out what's going on and looking for leaks in my argon line. I even took apart my machine and checked the solenoid and the torch port. All good. I've been using 2% ceriated since that's what came with my machine. But today my shipment of CK LaYZr rods came in so I figured I'd try it out. The results below show the difference. Settings are exactly the same:Mild steel 1/8" (two pieces welded together though so the thickness is actually 1/4")90 AmpsNo fillerBoth tungsten are 3/32" so the exact same collet for both I ran the top bead with the 2% ceriated. Switched to the CK, then ran the other bead. Quite the difference. The top one is all grainy and uneven: sunken in some areas, raised in other areas. The bottom one is perfectly flat and smooth (since no filler used, this is what I expected).The 2% ceriated was freshly ground but the shank probably wasn't clean and had some oxides on it from a previous mistake. Could that cause it? Still weird.
Reply:Check your collet and collet body conditions. The parts that come with the factory torch are atrocious. I order made in usa from TecTorch for my aircooled torches and they flow argon much better.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:
Originally Posted by shovelon
Check your collet and collet body conditions. The parts that come with the factory torch are atrocious. I order made in usa from TecTorch for my aircooled torches and they flow argon much better.
Reply:How are you cleaning your metal? It looks like something fairly coarse was used, and sometimes that means junk gets left behind to contaminate your weld. The close you can get it to a mirror before wiping down with acetone, the better. The shinier it is, the less places there are for contaminants. The top bead looks like what happens when people forget (not me, I never do that....lol) to turn on the gas or check the flow rate, or accidentally try DCEP on steel...that brown, nasty coating. Are you sure the collet is in properly....with the skinny part forward? They'll work backwards but the gas flow is drastically reduced.You have 1/4" steel....turn the machine way up....running something low like 90A simply won't help anything at all. For some reason many new folks think they'll be safer setting the machine low and then struggle. 1 amp per thousandth of an inch of stock is the general rule....you don't have to go that far, but something like 150A would be a lot more in the ballpark for just getting a puddle started. Tri-mix tungstens like the CK LAYzr are great for robots or people who really, really know what they're doing. Arc gap is a critical factor in making the most of them....probably not the strong suite for anybody just starting out. I've tried several brands of the tri-mix style and the only difference I see is that they're a touch better at holding a point on AC. The difference is so minor I don't think it's worth the added cost. For everything else you would make your life a lot simpler by sticking to 2% lanthanated until you've got a lot more experience....and it'll be a lot cheaper.Check out my bench vise website: http://mivise.comMiller Syncrowave 250DXMillermatic 350P with XR AlumaProMiller Regency 200 with 22A feeder and Spoolmatic 3Hobart Champion EliteEverlast PowerTig 210EXT
Reply:Something gas related, as most TIG problems are.Murphy's Golden Rule: Whoever has the gold, makes the rules.
Reply:What is the gas ? What is the gas flow ? What is the tungsten to work distance ? What is the stickout ? What size cup ?
Reply:
Originally Posted by G-ManBart
How are you cleaning your metal?
Reply:
Originally Posted by Mach_Zero
The reason I had it at 90 was because I was trying to practice that lap joint on these 1/8" pieces before and too much current would blow out the top edge too much.
Reply:
Originally Posted by Kelvin
If you're 'blowing out the top edge' on a lap joint, that suggests to me that you're not putting your heat where it needs to be. In a lap joint, you should focus most (say 2/3 of) your heat on the bottom piece. Once you get a puddle started on the bottom piece, work the edge of the puddle over toward the edge of the top piece in the lap joint. The puddle -- not your arc -- should be what melts the edge of the top piece in a lap joint. Even though both pieces are the same thickness, the bottom piece is, in effect, "bigger" because you're starting a puddle in the middle of the bottom piece, whereas you're starting a puddle on the edge of the top piece.Think about where the heat is escaping to the surrounding metal ... on the bottom piece in a lap joint, the heat has two avenues of escape, but on the top piece, where you're melting an edge, the heat has only one avenue of escape. Hence, the heat "piles up" on the edge of the top piece and blows out, as you found...this is why you need to work on establishing a puddle on the bottom piece first in a lap joint. On a more general level, with TIG, you're usually better off giving it more throttle for a shorter length of time, than in giving it less throttle for a longer time, due to "heat soaking" ... this is especially true with aluminum but also true with steel. So before you argue with the advice you've been given, try it.
Reply:
Originally Posted by Mach_Zero
I used a 120 grit sandpaper disc on a drill attachment. I could definitely get it cleaner but still both beads were run using the exact same conditions.
Reply:
Originally Posted by G-ManBart
Just to eliminate it as a variable, try to get a piece super clean...like a mirror if possible, then wipe down with acetone. It may not help, but you'll know for sure it isn't contributing to the problem. Sorting TIG issues like this can be frustrating, so the fewer the variables, the better.
Reply:
Originally Posted by Mach_Zero
Great idea. I'll do that. I welded a corner joint with the same steel using the LaYZr today and it didn't spark at all but it did leave some little deposits on the surface of the bead. So it's likely that I'm not getting it too clean. Oh they were actually cheaper than the lanthanated on Amazon. The 10 pack 3/32 from CK are like 24-25 bucks and I got this 10 pack of CK LaYZr for 20. So I didn't think I was spending extra to get them lol. But good to know that they're good electrodes! Interesting. For me it's the other way around. I got a great looking aluminum weld. No soot or anything on it. Just used 30% EP balance and it looked great. Then I got those weird results with steel. I wonder if it could also have something to do with the stock crappy vulcan cable. I have to sling it over my shoulder and really muscle it into position. Maybe I kinked it or something? I don't know. The new CK superflex cable is on the way so we'll see. I really appreciate your help G-ManBart!
Reply:
Originally Posted by Mach_Zero
Good idea. I suppose it also can be intermittent issues with argon coverage. Maybe when I switch out the tungsten it shifted the collet to a better position? I have a couple new collets on the way but I haven't ordered a collet body. I figured the body has more mass and doesn't wear as quickly and the thin collets. Should I upgrade? Those wedge collets from CK look interesting.
Reply:
Originally Posted by shovelon
You really might want to invest in one of these. Checks your gas flow at the torch. If it does not match the gauge you need to figure out why.
Reply:
Originally Posted by Mach_Zero
Thanks! I'll get one of those. I'm wondering if I should upgrade the regulator too. The one I have is one of those cheap ones that have two gauges and says Argon/CO2. The torch looks pretty good and I can feel flow coming out but I would also like to get a gas lens eventually.
Reply:Ever seen a kitchen faucet with aerator missing? Water blasts out, splashes all over the place. Screw on a clean aerator. all the splattering goes away. A gas lens is a faucet aerator. Helps calm the turbulence. I use one mostly ALL welds.Are you sure you are welding Electrode Negative?An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:Maybe bad gas if worse on aluminum. Worked at a place that had a lot of argon returned because they didn't purge the cylinders before they were filled. Expensive mistake. Something happened and their CO2 bulk tank got contaminated. I thought the EPA was going to show up with the huge cloud of CO2 being released into the atmosphere.
Reply:
Originally Posted by Willie B
Ever seen a kitchen faucet with aerator missing? Water blasts out, splashes all over the place. Screw on a clean aerator. all the splattering goes away. A gas lens is a faucet aerator. Helps calm the turbulence. I use one mostly ALL welds.Are you sure you are welding Electrode Negative?
Reply:
Originally Posted by Willie B
Ever seen a kitchen faucet with aerator missing? Water blasts out, splashes all over the place. Screw on a clean aerator. all the splattering goes away. A gas lens is a faucet aerator. Helps calm the turbulence. I use one mostly ALL welds.Are you sure you are welding Electrode Negative?
Reply:You have more spatter than I expect. The whole area is blackened. Either you are holding too long an arc, too much stickout, an air leak in the torch, or contaminated tungsten. Grinding tungsten everybody does something different. Some will say I do it wrong. Where the collet grips the tungsten to the point is perhaps 3/4". I grind that length if contaminated. I use a dedicated bench grinder with two grooves worn in the fine stone. It lays on its back so the wheels turn away from me. I grind a handfull of tungstens to shape, then switch grooves to perfect the point. Tungsten for steel gets a needle sharp point, aluminum gets a more blunt shape. In the torch the white washer, then gas lens tightened finger tight, then ceramic cup I often use a #7 cup. Gas flow usually about twice the CFH as cup size.Tungsten, collet, washer & tail cap last. Don't get long with stick out if you don't have to.Arc length 1 thru 1-1/2 times tungsten diameter. Outside corners are tough. I believe gas fails to get into the joint & stay pure. A block of aluminum clamped inside the corner when you weld it will trap gas that might blow around inside the box. Grind the corner of this aluminum block.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:
Originally Posted by 12V71
Polarity is a good point, Positive polarity is going to decimate the tungsten. IIRC, it takes a 1/4" tungsten to handle 200 amps DCEP.
Reply:I think the easiest thing to do is just try a new, maybe different tungsten?
Reply:
Originally Posted by Welder Dave
I think the easiest thing to do is just try a new, maybe different tungsten?
Reply:
Originally Posted by Willie B
I haven't figured this out. Can't help thinking 5 minutes with Shovelon, you'd be fixed.You have one minor problem, figure it out, you're golden.Buy me a round trip plane ticket, I'll get there, call Shovelon, I'll fix you.
Reply:
Originally Posted by Mach_Zero
Lol that would be awesome (if I could afford it). I'm gonna super clean some mild steel coupons and super clean the tungsten. Then I'll weld a T joint or something similar and post the results. So far it works great on aluminum so that's why I've been confused. Everything I've read or seen online has said that tig welding aluminum should be more difficult but now in my experience.Steel must be ground for TIG welding. No solvent or soap is a substitute. Acetone after.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:
Originally Posted by Mach_Zero
Lol thanks Welder Dave. I mean that was the entire premise of my post though. I tried a new tungsten and it worked way better. So I was just asking if it's possible for an electrode to go bad. Ultimately I think the issue is that even though I had ground in a new tip, I hadn't cleaned the oxides on the shank of the tungsten electrode that I thought was the problem.
Reply:
Originally Posted by Willie B
I wonder about a machine malfunction sticking on AC. I experimented once DC EP for aluminum. The sparks were like sparklers on independence day! Aluminum AC with balance reversed IE 80/20 EP will spark bad! 80/20 EN might not do enough to cathodically clean (I learned that from Shovelon), but no fireworks. I haven't figured this out. Can't help thinking 5 minutes with Shovelon, you'd be fixed.You have one minor problem, figure it out, you're golden.Buy me a round trip plane ticket, I'll get there, call Shovelon, I'll fix you.
Reply:
Originally Posted by Welder Dave
I wasn't trying to be smart. Most tungsten comes out of China... and have heard of bad tungsten like Lanthanated splitting. A lot of people still prefer 2% thoriated with an inverter. Only reason some suppliers dropped it is they think it's going to turn weldors into Spiderman because it has slight amounts of radiation.
Reply:
Originally Posted by Mach_Zero
Oh sorry I thought you were being facetious. The tungsten that was giving me issues could be a cheap one since it came with a Vulcan machine (it's 2% ceriated just in case anyone was wondering). And the new stuff I got was from CK so I think it was good. But I think there was probably something else going on like me not cleaning the rest of the tungsten and not jusr grinding the tip. I've been messing around more and more and just noticing little things while tinkering. I'd like to get a gas lens and just upgrade the torch eventually. First step is the new power cable that is arriving hopefully tomorrow (shipping was delayed
). Thanks for your help!I'm definitely learning this lesson the hard way. Cleaning is so tedious at times I do a lazy job. But I'm realizing the only way you'll get nice welds is if the base metal is very clean. I'll have to pick up some acetone tomorrow. Then I'll weld that test coupon and report back. At any rate, despite the hiccups tig welding is a lot of fun. I appreciate everyone in this forum for helping me out. Also if anyone has some good recommendations for a gas lens, let me know. (Not looking for the huge cups, just some standard cup sizes with the gas lens)
Reply:Ok so it's definitely a gas coverage issue. I was struggling again with some simple butt and outside corner joints on some test pieces, even with carefully ground tungsten and sanded metal (not acetone clean, but pretty clean). I bought a consumable kit online that came with all the stubby consumables as well as stubby gas lens consumables. First try with the new collet body, collet, and ceramic cup (non gas lens) and I had a perfectly clean weld with no porosity or sparks. And this was with the same tungsten diameter and same ceramic cup diameter I had been using. Old collet body must have some issues or something. Switched to gas lens and #10 Pyrex glass cup (just because it looks cool lol) and same clean weld bead. Even on a dirty butt joint it still left a really nice weld. The puddle was dirty and it left some deposits on the top of the bead (scrap test pieces), but no sparks or porosity. And the Pyrex cups are awesome! Lesson learned! Sparks means no gas coverage. Makes sense since I would imagine sparks can only occur in the presence of oxygen. Even a contaminated weld shouldn't spark if there's no oxygen for it to burn.I'll stop being lazy and cut some test coupons and really get them perfectly clean for a weld. Then I'll post some pictures and see what you guys think.
Reply:
Originally Posted by Mach_Zero
Ok so it's definitely a gas coverage issue. I was struggling again with some simple butt and outside corner joints on some test pieces, even with carefully ground tungsten and sanded metal (not acetone clean, but pretty clean). I bought a consumable kit online that came with all the stubby consumables as well as stubby gas lens consumables. First try with the new collet body, collet, and ceramic cup (non gas lens) and I had a perfectly clean weld with no porosity or sparks. And this was with the same tungsten diameter and same ceramic cup diameter I had been using. Old collet body must have some issues or something. Switched to gas lens and #10 Pyrex glass cup (just because it looks cool lol) and same clean weld bead. Even on a dirty butt joint it still left a really nice weld. The puddle was dirty and it left some deposits on the top of the bead (scrap test pieces), but no sparks or porosity. And the Pyrex cups are awesome! Lesson learned! Sparks means no gas coverage. Makes sense since I would imagine sparks can only occur in the presence of oxygen. Even a contaminated weld shouldn't spark if there's no oxygen for it to burn.I'll stop being lazy and cut some test coupons and really get them perfectly clean for a weld. Then I'll post some pictures and see what you guys think.
Reply:
Originally Posted by Mach_Zero
Lesson learned! Sparks means no gas coverage. Makes sense since I would imagine sparks can only occur in the presence of oxygen. Even a contaminated weld shouldn't spark if there's no oxygen for it to burn.
Reply:
Originally Posted by shovelon
It is amazing how a nice gas flow improves quality and productivity. After playing around with it you can actually lower your flow to save gas, then when hit the bottom limit raise a tad. I found only standard collet bodies with extended ceramic nozzles flow argon well. I guess the length of the inside gives the turbulence a chance to dissipate. I do use standard extended cups for getting into deep places, and have basically mothballed my short ones. Gas lenses are the shizzle.
Reply:
Originally Posted by Mach_Zero
Yeah you're definitely right. I just couldn't figure out why my aluminum welds looked perfectly fine (any ugliness was purely due to my technique, not the argon coverage lol). But then steel was giving me the issues. I was trying to hold off on getting a gas lens because I've read online and seen videos where people advise you learn on standard consumables to develop proper technique, then later you can get the fancy gear. The ceramic cup I was using is one of the longer ones, and I still can't figure out why it was giving me issues. Do collet bodies wear out or something? Even with a new collet it was giving the same results. But even with the new stubby collet body (non gas lens) I was getting great coverage. I can't wrap my head around what went wrong with the original collet body. It came with the machine and was used quite a bit by the previous owner, but still it looks ok. Just a little discolored from the heat. Maybe the ceramic cup was dirty and causing those issues? I have two ceramic cups that came with the machine, #5 and #8, and both were giving me issues. So that's why I feel like it's the collet body rather than the cup. No idea. Ha! Yeah plenty of learning to do in this hobby. But it's been a fun journey.
Reply:
Originally Posted by shovelon
Yes collets wear out. But more often bad collet bodies screw up the gas flow right off. Not that I hate standard collet bodies, I have had much better success with the gas lens.
Reply:
Originally Posted by Mach_Zero
This is really good to know! That's a relief. Upon inspection, the collet body looked fine other than the copper discoloration/oxides from heating. But yeah the gas lens is incredible.How about the gas lens? Do they wear out and go bad too? And if so, do they last longer or shorter than standard collet bodies? I would assume longer if anything since they have the diffuser. |
|
发表于 2021-9-1 23:18:05