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I know this is a very ugly weld but I have been only trying to weld Aluminum for three days now. I am trying to figure out what I need to do to make it a clean weld. Any ideas or help?Thanks for any help you can give. The extra heat someone suggested really helped out at least getting a bead going.
Reply:In my limited experience with aluminum, my first thought was "too slow" movement (noting the build ups). But I am eagerly watching to see what the pros say.It's not what you can buy, it's what you can build.
Reply:jemaddux, youre not giving us enough information. What is the thickness of the work, the rod size and type and brand of welder?
Reply:I've seen (and made) worse but you still need more heat. What are your material and welding parameters?MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Whoa, that Tig machine is doing a lot of cleaning. Looks like the metal was cleaned prior to welding, but did you grind it back to get rid of the oxide layer?MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Material is 6061 Aluminum .078 thickRod I am using is 3/32 4043Using 3/32 pure Tungsten (green)My Machine is a Lincoln Precision TIG 185 with straight Argon tank.I used break cleaner to clean the area and then used a Scotch Bright pad to do a final little clean.
Reply:I do not know what others are going to say, but for me. I say turn the heat up a little more, and slow down your torch hand,( Right hand for me) but speed up your dippipng hand(left hand for me). Anytime you do a fillet weld you can not do a dip then move like you do on a horizontal weld. Fillet welds need LOTS of filler material. If you look at the part I marked in red. That is almost exactly what you want it to look like.But hey, it's only my 2cents. Attached Images
Reply:Thats about the only part that looked half way good was the area you marked in red. Like I said before, I can't beat myself to bad about this, I only really have about four hours of trying Aluminum welding in right now. I am hoping I can only get better.Last edited by jemaddux; 07-03-2009 at 12:11 AM.
Reply:What does the backside look like, penetration?
Reply:"I can't beat myself to bad about this, I only really have about four hours of trying Aluminum welding in right now."You have nothing to worry about. In time you will have it down.
Reply:Well to me the bit you've marked in red needs more filler, the rest looks about right in that department, the first couple of inches aren't far off.You just need to get a better rhythm going to to get a more uniform looking weld, weather that be doing circles or some kind of whip motion only you can find out. What I can tell you is your close, I would say whatever your doing do a bigger 'motion'.I'd rather be hunting........USE ENOUGH HEAT.......Drifting around Aussie welding more pipe up, for something different.....wanting to get home.
Reply:Remove the oxide layer in the weld area prior to welding (regardless of the process used to weld it). Aluminum melts at around 1200 degrees F. The oxide layer (the shiny outer surface) melts at around 3200 degrees F. If you fail to remove the layer, it's possible to have the pure aluminum underneath already molten when you finally have the oxide layer hot enough to melt through. This can cause "collapse" in the arc area.I use a SS wire wheel on a 4 1/2" angle grinder to remove the oxide layer. Chemicals aren't going to do it. If I have to clean more, always use SS brushes. Never use sand paper or emery paper. They will leave unwanted deposits in the weld area.Even if I'm welding an ear back on a transmission or transfer case, I ALWAYS remove the "oxide" layer.Good luck with future aluminum welding. You're getting there.
Reply:Originally Posted by wirehuntWell to me the bit you've marked in red needs more filler, the rest looks about right in that department, the first couple of inches aren't far off.You just need to get a better rhythm going to to get a more uniform looking weld, weather that be doing circles or some kind of whip motion only you can find out. What I can tell you is your close, I would say whatever your doing do a bigger 'motion'.
Reply:You are set way too cold. The last part marked in red is where the heat built up in the AL and you were actually hot enought to get the filler to flow properly. There still isn't enough filler there though. I would guess that your puddle never really connected between the two pieces and you are bridging across the root with the filler. two shiny little puddles that don't meet at the root = bad. You are set right right when the leading edge of the puddle is a shiny silver and you can see it hitting the root of the joint before you dip your filler. I would bump your amps up 50% at least. The key to AL is to try and weld fast enough to keep up with amps without burning through. If you have to drop off on the amps near the end of the weld so you don't burn through you were doing it right.
Reply:If you're using some kind of square wave inverter get rid of the green tungstens and use a pointed gold one or something to get a more focussed arc.
Reply:You are not too bad just give it a little more heat, clean with a ss brush, and give yourself a nice ball on the end of that tungsten, not too big. Once you get the puddle going be steady with your hands (use a steady rest if possible) And consistancy is most important when trying to get a "nice" looking bead. Make sure to keep your rod in gas coverage at all times while welding, Dip your rod at the front edge of the puddle and let a bead form once you have that, just keep going. When at end of plate slowly bring your foot off the petal and swirl your tungsten out while dipping one last time to prevent any "Crater Cracks". NEVER pull your tungsten away fast. you will lose gas coverage."My fingernails are melting"
Reply:The first two priorities in TIG aluminum are cleanliness and oxide removal.First remove all foreign substances such as dirt and oil. Generally a solvent that does not leave a residue like acetone is good. A water detergent can be used first, then followed by acetone.Second, remove the surface oxide on all of the weld joint surfaces, top, bottom, and edge. Generally manually wire brushing with a clean stainless steel "tooth brush" is good. Only use this brush on clean aluminum so it will not pick up contamination like oil, dirt, or particles of other metals, that would be tranfered to your aluminum. You will feel the brush really start to grab the aluminum when you have broken through the surface oxide, it takes some elbow grease. A clean file can be used to remove oxide from the joint edge.A final wipe with clean cotton cloth, or cloth dampened with acetone, will remove light oxide dust remaining from brushing.I caution against aggessive power wire brushing since the high speed and pressure can produce enough heat to actually form oxide. Avoid agressive grinding of the finshed weld joint since like power brushing it can form oxide.Scotch Brite, flapper wheels, and other "sand paper" type abrasives are generally not a good choice since some use alumina as the abrasive, and regardless of the abrasive it may be deposited on the aluminum surface and contaminate the weld. Grit blasting could certainly cause the same problem of embedding contaminating grit.Now how about your filler rod, is it clean? It won't hurt to wipe the filler with acetone and clean cotton cloth prior to welding, If the filler wire is not acient and has be stored clean and dry, you shouldn't need to try to remove its surface oxide. Handle the wire with clean gloves to avoid contamination with hand oils or stuff off your crudy stick welding gloves.
Reply:There was an article in the AWS Welding Journal about 2 years ago. They suggested grinding the tungeston to a point for thinner gages. It will still ball up, but the ball will be very small. That works really well for me.
Reply:Originally Posted by wirehuntWell to me the bit you've marked in red needs more filler, the rest looks about right in that department, the first couple of inches aren't far off.You just need to get a better rhythm going to to get a more uniform looking weld, weather that be doing circles or some kind of whip motion only you can find out. What I can tell you is your close, I would say whatever your doing do a bigger 'motion'.
Reply:Like most others said, more heat and filler. Wait until you see the pieces melt together in the center of the joint. Then, and only then add some filler, watch it flow into the pieces and move forward a hair. Repeat.Have we all gone mad?
Reply:Originally Posted by Fat BastardI would agree the rhythm needs work, but what circles or whipping motion are you referring to?
Reply:The wife says your torch should be more vertical (no joke), you're welding the filler.
Reply:Never understood grinding the oxide off. It helps a little, but is it really necessary?Show of hands, how many of you wash your face before stepping into the shower?I remove any oils or foreign matter and let the AC take care of the oxide.
Reply:Boostin,Obviously you dont weld much aluminum.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIIBoostin,Obviously you dont weld much aluminum.Originally Posted by 3MTA3Could you possibly elaborate on this so that those who do not understand can benefit from your knowledge, or is it top secret information that would require that you dispatch of us after wards? Nothing wrong with a little poke to the side, but a little education/knowledge to go along with it would be great for those who need it. There is no doubt you have the knowledge. It is one thing to read it in a manual or instruction book, but to be able to benefit from the real world words of someone with your level of experience would be golden.3M TA3
Reply:3MTA3,Pretty simple really.Aluminum forms an oxide layer which melts at 3000+ degrees. The aluminum beneath the oxide layer melts at a much lower temp. This oxide layer begins forming immediately after being exposed to the atmosphere. Stainless steel wirebrushing tends to break up and remove (to a degree) these surface oxides, leaving the bare aluminum for welding.Not removing these oxides (relying solely on the DC+ cycle of the AC) is not generally a good idea. The DC+ breaks up the oxides, but does not really remove them. Prior cleaning with the SS brush will yield a "cleaner" and better bead. Also, for those with inverters, a higher frequency setting (less cleaning) will put more heat (DC-) into the workpiece and reduce the etched zone adjacent to the bead.Been said many times and is still true today. The trick to welding aluminum is to clean, clean, and then clean some more. Better the base material, the better the finished product. 75% of the effort in welding aluminum properly is in the prep.An exception to this, if you could really call it an exception (more of necessity) is bump welding anodized aluminum. Here the anodize (really an oxide) is much more difficult to deal with than normal oxidation. High amp bursts break up the oxide layer and allow the arc to reach the base metal beneath. It's done out of necessity, not because it yields a "better bead".Pretty easy to check out yourself. Cut a couple of aluminum coupons. Clean one set with a SS brush and leave the other bare (wipe with acetone/alcohol). Butt weld the two sets of coupons and tell me which you would be happier sending out of the shop as "your work". BTW. Clean both sides and the edge, not just the side you plan to weld. If not the oxides on the back side will be drawn into the bead.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Sundown, Thanks for elaborating on that in detail. My experience with aluminum is very limited. It is a great help to here this coming from someone who has that experience. Dave, I guess the humorous sarcasm was lost on you. As you mentioned it was said before and not to discount those posters in any way, it is nice to have confirmations of something from as many experienced pro's as you can get. It sort of plants it in a learning mind a little better. Like I said in my earlier post, there is nothing wrong with a little jab to the ribs. 3M TA3
Reply:Originally Posted by SundownIII3MTA3, Also, for those with inverters, a higher frequency setting (less cleaning) will put more heat (DC-) into the workpiece and reduce the etched zone adjacent to the bead.
Reply:Sn0,I can see where my comment may be somewhat confusing. Let me try to clear it up.We're really dealing with two issues here. Frequency and balance.The balance control on most tig welders controls the percent of time the machine operates in either the DC- (heat to workpiece) or DC+ (cleaning, more heat to tung). By precleaning the aluminum, you are able to increase the DC- portion of the cycle, thereby getting more penetration, better bead, faster movement (less overheating the filler).The increased Frequency allows the welder to better focus the arc. (Higher freq, tighter arc) The combination of the two, higher freq and reduced cleaning results in a better weld. The inverters also allow going to a higher percentage of DC- than is possible with the older squarewave machines such as a Sync 250.Properly set, an inverter allows a very deep penetration weld with almost no adjacent etched zone. By varying the frequency, the welder determines the bead width. One place where the higher frequency's really come into play is in doing a corner weld. The higher frequency allows you to much better focus the arc at the root of the joint.Sorry if I wasn't clear in the previous post.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIIBoostin,Obviously you dont weld much aluminum.
Reply:The thing that stuck out in my mind, was the width of the cleaning stripe. Maybe that's a symptom of balled green tungsten (which I have never used), balance set around 50% rather than my preferred 70-80%, or contaminated tungsten. I know that if I dip my tungsten and attempt to continue welding, the cleaning stripe increases in width 100% or more.
Reply:I do not know if anybody has noticed this. But with everybody jumping on each other, jemaddux has not been back.He asked for help and comments about his weld. How about we try to get back on track and help him out.jemaddux please let us know how this are going.
Reply:Originally Posted by partagasI do not know if anybody has noticed this. But with everybody jumping on each other, jemaddux has not been back.He asked for help and comments about his weld. How about we try to get back on track and help him out.jemaddux please let us know how this are going.
Reply:Aluminum is a huge heatsink, therefore to gain the welding puddle needed to properly join the material, PREHEAT the parts. My method when welding aluminum was move the arc back and forth over the joint once or twice, then hold the arc at my starting position until the mirror-looking puddle formed. It will most likely form on the top coupon first when welding a fillet joint, so focus most (read: 60-70% of the heat) on the bottom coupon. Don't begin to travel until this puddle is formed. You can see at the end of your joint when there was adequate heat.On cleaning, watch out using abrasive cleaning on extremely high quality welds. Some of the oxides can be forced into the base material that can cause problems on x-rays. I use OX-OUT to clean base material, just soaking in it for 4-5 minutes will clean it perfectly, electrical charge not really needed. Waiting over 5 minutes after cleaning to weld will not result in an A+ x-ray, don't wait longer than 2-3 to be on the safe side. Using this method of cleaning gave a 99.9% rate of A+ x-rays on orbital welding small (<1") tube to fitting.
Reply:More heat, you are globing the filler on top of the plate. I use slow steady torch moment and dip my filler bout every second or so. Get a peddle so you can back off the power after you get a puddle going. just remember you have to get a shiny puddle in the base metal. you will see it flowBrandonLincoln Tombstone 225 A/C Steel StickerOld Victor O2/Acetylene setupMiller Syncrowave 250 Tig/PC-300 PulserMiller Millermatic 212 Mig HTP Invertatig 201 Giant Teck D50 Plasma cutterLots of HF grinders
Reply:This should shed a little light on the subject @hand. Attached Images
Reply:cmartman46:what are those pages from?
Reply:http://weldingweb.com/attachment.php...1&d=1247637457 Attached Images |
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发表于 2021-9-1 00:44:36