Question on MIG and Aluminum

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Hello all!!!  I was researching some information on a Hobart Handler 140 and I came across a thread (here) that peaked my interest.Someone stated, and I quote, "Realistically, a 110V MIG is only good to about 1/8" for steel and stainless, and almost completely worthless for aluminum."Is this true?  How affective is 110V on aluminum?  I'm still an uber noob and trying to find out as much as I can as the questions arise.   I'll do this ( ) while I await a response. ***Stick welding like, woah.***
Reply:I don't know about aluminum, but i've used 110v wirefeeders that did 3/16" without a problem.  I've even welded 1/4" with them but that was pushing it and it was an open root.
Reply:Thanks WelderBoy!   I appreciate your comments!  ***Stick welding like, woah.***
Reply:Looking at the numbers, a 115vac MIG will only be capable of 1/8 with solid wire, and then just barely. With flux core, 3/16 to 1/4 is within its reach. I have run my MM135 with alu and it is extremely cold. Alu dissapates heat so rapidly, you need lots of power to kep it running correctly. When the 140/135 class units hit the max amperage, the voltage drops too much to make it effective on alu. I did it just to play around and see if it would do it. It will do short circuit easily...but with alu, that is exactly what you do not want. It takes a good balancing act to make it go into spray transfer. That is where alu needs to be. Short circuit welds will be too cold to be of any use. Fun to play with though.
Reply:I did it with my 110v lincoln. I will give you some advice: 1. Teflon liner. 2. Oversize tip. Use .035 wire, and a .040 tip. 3. Use 5356 wire, not 4043. 5356 is stiffer, and you will need that. 4. Keep you gun line as straigt as possible. "You can't push a rope." Aluminum mig wire is rope- soft. 5. PREHEAT. Use a mapp torch. It works better than oxy/ acetaline for preheat on aluminum because: there is no added oxgen. Extra oxygen, with high heat= oxidation on the aluminum. If you DO USE oxy/ acetaline, use a rich mixture- just hotter than running sooty. As little oxygen as you can to keep a torch running clean.6. PUSH the wire. Don't pull. speed high-7 or 8. Heat/ volts??? MAXIMUM.7. Learn to hate aluminum wire as it jams in the gun, jams in the rollers, jams in the sleeve. Just learn to hate mig welding aluminum. I did my engine box on my boat this way. It was 1/4" material. You have to clean like crazy, preheat to 400-500 degrees on the seam you will weld, you will just HATE the wire jamming every 10-30 seconds. But, yes, it can be done. I spent a lot of money on a tig welder, so I don't have this problem anymore. And, I have a 220v mig, I am getting another spoolgun just for doing aluminum with it. The spoolgun is the way to go for mig on aluminum. But not practical for a 110v machine. (Spoolgun costs as much as a 110v machine...) If you have any more questions about it, let me know. I did this for several weeks, so I am certain I am right in my utter disgust with the entire process!!! I wish you GOOD LUCK!!!! And, the patience of a saint. You're gonna need it.....And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:DDA52, Just for clarification.  A 120V 135A Mig will not come close to reaching the amps necessary to achieve spray transfer.A 180A class machine (HH187, MM180, etc) will do an acceptable job on 1/8 to 3/16 aluminum if equipped with a spoolgun.  These machines are operating in a short circuit transfer mode, not spray.  They also lack the amps to go to spray transfer.The 200+/-A machines (HH210, MM210/212) will go to spray transfer mode but are severely limited in duty cycle at those amps.  Spoolgun equipped, these units will do a great job on 1/4" aluminum in short circuit transfer mode.Realistically, a MM251/252 (or comparable) is the minimum machine where consistent spray arc transfer becomes practical.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:This is from Miller's GMAW book appendix, section XX, table 3...ALU parameters. Spray transfer with .030 4043...20-27 volts, 95-200 amps, 550-1200 IPM......035 4043....20-27 volts, 110-220 amps, 425-850 IPM. All parameters with straight Argon for shielding.So, with those numbers at play, with perfect conditions, a 135/140 class MIG COULD reach spray.  Mine did go into spray for brief spurts, but was not sustainable for very long when the voltage dropped. Yes, I do know what spray alu is and that was it. Was it useable, no...did it do it, yes for a very brief time.Last edited by DDA52; 08-28-2007 at 10:53 AM.
Reply:DDA52,I stand by my comments in the previous post.I really don't think we're as far apart on opinions as it may seem though.  I will disagree with your comment about spray transfer being the only way to really weld aluminum (or words to that effect).  I have achieved good results with an HH187 and spoolgun on aluminum up to 3/16" in short circuit mode.I have no experience with the MM135 or MM140 so all I have to go by is the manufacturers specs.  I did at one time (no longer--gave to son) own a HH140 Mig.  Trying to push aluminum (even 5356) thru 10' of liner can (in my own words) be described as an exercise in futility.  Just when you think everything is going fine, you turn the gun slightly, bam, birdnest.Back to spray transfer with a MM140.  I see your numbers (have the same GMAW book).  Also see the specs for the Miller 140 from their product literature.  140 is rated at 90A @ 18VDC at 20% DC and 63A @ 21VDC at 20% duty cycle.  WFS is 40-500 IPM.  Per your numbers, spray transfer requires a minimum of 20VDC @95-200A at a WFS of 550-1200IPM.  HOUSTON--we have a disconnect.  If nothing else, the 140 will not even achieve the minimum WFS necessary for spray transfer with 4043 aluminum wire.  If you got a spray transfer from a MM135, and I'm sure (if you say so) you did, it was a spit and not a weld.  Sorry, just not going to happen.In summary (a restatement).  If one wanted to weld aluminum (with any regularity) a 180 class machine (w/spoolgun to avoid frustration) is the bare minimum and then should only plan on doing short circuit transfer welding.Those more serious about welding aluminum should be looking at the 210A class machines (duty cycle) equipped with a spoolgun.  Even with this class of machine spray arc welding aluminum will be severely limited due largely to duty cycle.Enter the MM251/MM252 and then the MM350P.  That's really where spray arc aluminum welding begins to make sense.I know this will probably create a stir and a lot of posters will say "Well, I've done this and I've done that", but I think you'll find that the serious MIG guys on the board will agree with the position I've stated.Just my .02   FEEL FREE TO BLAST AWAYSyncro 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 DDA52With flux core, 3/16 to 1/4 is within its reach.
Reply:For aluminum spray, BIG all the way. My Esab MM260 with the spoolgun does a nice job and ditto on the other large machines. I have a Harbor Freight 105A unit (240VAC) unit that will start to spray, but quits quickly as the rectifier heats up.  At this point, the tip jams. Keep it in short circuit and it welds 1/8" just fine.Speaking of rectifiers heating up...if you have a machine with an automatic cooling fan, you will notice that your machine is happier when doing a lot of spray aluminum at high amperage if you rewire the fan to be on hi speed at all times. Consistancy in the power supply makes for a good weld and when you have a rectifier whose temperature goes up and down all the time, you can notice a difference.
Reply:Sundown.....read my posts. I said the 135/140 class units were not very effective for alu. What part of that is so difficult to understand? I am not endorsing the units for alu at all. I said they were ok to play around with alu, that is all. My MM135 has a WFS that tops out at 750ipm.....that puts it into the parameter easily. BUT I also said the voltage drops too rapidly to make it useful. Best I could ever achieve is about a half inch or less of spray bead before it crapped out. The parameter are there on paper, but extremely difficult to hit in real practice. That is why I stated under perfect conditions it COULD do it, not that it actually would. Technically it is possible, but not very doable. Short circuit all the alu you want. I prefer spray as do all my engineer's specs I have to deal with. Short circuit is the only way to do below 1/8 effectively anyway. I short circuit 14ga all the time. But am always in spray above that. I am done with this now. My posts were in English and were not vague. Read into it all you want. I just have better things to do than argue about this when I don't need to.
Reply:DDA52  Clarification.Yes I did "read" your posts (both of them). And, no I do not have a problem with the English language.The reason I responded in the first place was because I felt the posting was inaccurate/misleading and lacking in substantiation.  You wrote, "It will do short circuit easily...but with alu, that is exactly what you do not want.  It takes a good balancing act to make it go into spray transfer.  That is where alu needs to be.  Short circuit welds will be too cold to be of any use."To me, that is an inaccurate statement.  Nearly all MIG welds on aluminum less than 3/16" thickness are done in short circuit transfer mode.  Personally, I wouldn't even attempt to spray transfer weld aluminum less than 1/4".  Just too much heat.  If you're spray transfer welding "all" aluminum thicker than 14 gauge, you're a much better mig welder than I am.  I can assure you I can get a code passable weld on 3/16" aluminum using short circuit transfer.The implication in your first post was, as I read it, was that no one should weld aluminum utilizing short circuit transfer.  That is wrong.In your second post you stated that your MM135 had a max wire speed of 750IPM so that easily put it into the range for doing spray transfer.  Didn't seem quite right to me why there was so much difference between the MM140 and the MM135, so I went to the Miller site and looked up the specs (per owner's manual) for the MM135.  You must have one of the "souped up" wire feeders on your machine, because all the other MM135's have a wire speed range of 20-600IPM Feeding Wire.  (Per page 9 of the MM135 owners manual) While that barely meets the WFS requirements for spray transfer, the other parameters (V, A, etc) do not.I'm not trying to start a fight or anything, but I felt it important that we don't mislead some of the less experienced guys on the board.LaterSyncro 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:DDA52,I agree with you 100%.Aluminum should be sprayed not short arced. If it's too thin for spray then use a pulse spray. If you don't have that then TIG it. If you are welding a new hat hanger for your wife than yes, short arcing welds will get you by. If you are talking about something that is going to see real stresses and strains then no short arc is not appropiate. Short arc aluminum and you are just asking for lack of penetration defects.I already know what response I am going to hear ,about how TIG will take too long, etc, etc,. So think on this. How much time is someones safety worth when a weld fails?Arguing with a Welding Engineer is like wrestling with a pig... after a while you realize the pig likes it
Reply:Can someone explain the spray arc vs short arc methods to me. I was under the impression that the welder had to be capable of doing one or the other. I have a Lincoln pro MIG 180, will it do both methods and if so is it a automatic process and how do you tell if it is spray arc or short arc welding. I am planning on buying a spool-gun for my welder so I can weld .125 and thinner aluminum, will this setup be able to do a good enough job for making such things as tote trays for small hand tools and such. Thank you for any info you guys can give me to better understand welding aluminum.
Reply:Here is what Miller has to say concerning short arcing of aluminum. We can believe Miller now can't we? After all they have been in this industry longer than any of us have been alive."- Spray transfer is the desired mode of metal transfer for welding aluminum. The spray transfer is a very smooth transfer of molten metal droplets from the end of the electrode to the molten pool. The droplets crossing the arc are smaller in diameter than the electrode. There is no short-circuiting in spray transfer. With spray transfer the deposition rate and efficiency is relatively high. The arc is very smooth, stable, and stiff and the weld bead has a nice appearance and a good wash into the sides. In the spray transfer a large amount of heat is involved which creates a large weld pool with good penetration that can be difficult to control and can not be used on materials thinner than 14 Ga. This transfer will produce a hissing sound, and no spatter.- The short arc transfer on aluminum produces poor cleaning action, poor tie in at the edges of the weld, and large amounts of spatter and smoke."Maybe we should listen to what Esab has to say."The most common and preferred method for welding aluminum is with the spray arc process, regardless of the material thickness or position of welding. The high heat conductivity of aluminum is such that even with the high heat input produced with a spray arc, the solidification rate of the weld puddle is rapid enough to allow welding out of position. Pure argon shielding gas is most commonly used for semi-automatic (manual) welding as the weld puddle is very controllable and the resulting weld exhibits good bead shape and soundness. However, if a hotter puddle is desired, for thick plate or automatic welding for example, argon- helium mixtures may be used. Although the short arc process may be used for welding extremely thin aluminum, spray arc should be used when- ever possible. If care is not taken to provide a clean welding surface, the fast freezing puddle produced by the short arc process is very likely to yield porosity. The welding conditions appearing in Table 8-4* were developed using argon shielding gas and the spray arc" I don't think 3/16 qualifies as extremely thin.Arguing with a Welding Engineer is like wrestling with a pig... after a while you realize the pig likes it
Reply:Originally Posted by 737mechanicCan someone explain the spray arc vs short arc methods to me. I was under the impression that the welder had to be capable of doing one or the other. I have a Lincoln pro MIG 180, will it do both methods and if so is it a automatic process and how do you tell if it is spray arc or short arc welding. I am planning on buying a spool-gun for my welder so I can weld .125 and thinner aluminum, will this setup be able to do a good enough job for making such things as tote trays for small hand tools and such. Thank you for any info you guys can give me to better understand welding aluminum.
Reply:Originally Posted by 737mechanicCan someone explain the spray arc vs short arc methods to me. I was under the impression that the welder had to be capable of doing one or the other. I have a Lincoln pro MIG 180, will it do both methods and if so is it a automatic process and how do you tell if it is spray arc or short arc welding. I am planning on buying a spool-gun for my welder so I can weld .125 and thinner aluminum, will this setup be able to do a good enough job for making such things as tote trays for small hand tools and such. Thank you for any info you guys can give me to better understand welding aluminum.
Reply:I usually see 22-24V when spraying 3/64" 4xxxWhen the guy with the TIG gets done welding 1", I just went 16" with the spoolgun!
Reply:Reddoggoose,Since many of your posts/opinions seem to go against conventional field wisdom and generally accepted practice I'd like to ask a few questions so I can better understand where you're coming from.What degree does a "welding engineer" actually hold?  The reason I ask is because my BS is in Civil Engineering and MS is in Industrial Engineering.  Both are commonly recognized degrees in any engineering school in the country.  I have never heard of a BS in "Welding Engineering".  I certainly hope that this doesn't fall into a similar category as a "Sanitary Engineer, AKA Garbage Collector".What school did you graduate from and when?What is your practical, real world, welding experience and what equipment/processes are you experienced in and to what extent?You seem to have all the AWS codes "right at your fingertips".  What company do you currently work for and what is your job description?It would seem that a person with your "extensive knowledge" would be highly sought after by companies such as Miller and Hobart.  After all, it would appear that they do need to rewrite all their Mig Owner's Manuals cautioning owners against using short circuit transfer to weld aluminum.  I guess both Miller and Hobart will just have to redo all their door chart welding parameters as well.  Also Miller will also have to rewrite their Gas Metal Arc Welding manual.  Wow.  That could keep you busy for some time into the future.Answers to the above questions would surely help me better understand what you base your responses on.Thanks in advance.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:Reddog, you took the words right out of my mouth and hands. I finally found my alu stuff, well some of it. There is still an Alcoa book that is MIA. But the Miller one I have in my hand. The bulliten is "GMAW(MIG) Aluminum Welding Hints #211162A. The section is #2, Welding hints and the points are #'s 4 and 5.I don't make this stuff up. Now for the MM135. I have my book right in front of me and it states 750ipm max. It is an older unit and yes, it does run hot. It even has parameters on the door chart for running .035 solid wire. Again, I do not make this stuff up. I'd take a pic, but my camera is down for the count.
Reply:Originally Posted by SundownIIIDDA52  Clarification.Yes I did "read" your posts (both of them). And, no I do not have a problem with the English language.The reason I responded in the first place was because I felt the posting was inaccurate/misleading and lacking in substantiation.  You wrote, "It will do short circuit easily...but with alu, that is exactly what you do not want.  It takes a good balancing act to make it go into spray transfer.  That is where alu needs to be.  Short circuit welds will be too cold to be of any use."To me, that is an inaccurate statement.  Nearly all MIG welds on aluminum less than 3/16" thickness are done in short circuit transfer mode.  Personally, I wouldn't even attempt to spray transfer weld aluminum less than 1/4".  Just too much heat.  If you're spray transfer welding "all" aluminum thicker than 14 gauge, you're a much better mig welder than I am.  I can assure you I can get a code passable weld on 3/16" aluminum using short circuit transfer.The implication in your first post was, as I read it, was that no one should weld aluminum utilizing short circuit transfer.  That is wrong.In your second post you stated that your MM135 had a max wire speed of 750IPM so that easily put it into the range for doing spray transfer.  Didn't seem quite right to me why there was so much difference between the MM140 and the MM135, so I went to the Miller site and looked up the specs (per owner's manual) for the MM135.  You must have one of the "souped up" wire feeders on your machine, because all the other MM135's have a wire speed range of 20-600IPM Feeding Wire.  (Per page 9 of the MM135 owners manual) While that barely meets the WFS requirements for spray transfer, the other parameters (V, A, etc) do not.I'm not trying to start a fight or anything, but I felt it important that we don't mislead some of the less experienced guys on the board.Later
Reply:May be, Vipernut, but at least I can prove I am not misleading anyone. With Miller and Esab saying the exact same thing, I don't see the need to bring out the Hobart reference.
Reply:Originally Posted by SundownIIIReddoggoose,Since many of your posts/opinions seem to go against conventional field wisdom and generally accepted practice I'd like to ask a few questions so I can better understand where you're coming from.What degree does a "welding engineer" actually hold?  The reason I ask is because my BS is in Civil Engineering and MS is in Industrial Engineering.  Both are commonly recognized degrees in any engineering school in the country.  I have never heard of a BS in "Welding Engineering".  I certainly hope that this doesn't fall into a similar category as a "Sanitary Engineer, AKA Garbage Collector".What school did you graduate from and when?What is your practical, real world, welding experience and what equipment/processes are you experienced in and to what extent?You seem to have all the AWS codes "right at your fingertips".  What company do you currently work for and what is your job description?It would seem that a person with your "extensive knowledge" would be highly sought after by companies such as Miller and Hobart.  After all, it would appear that they do need to rewrite all their Mig Owner's Manuals cautioning owners against using short circuit transfer to weld aluminum.  I guess both Miller and Hobart will just have to redo all their door chart welding parameters as well.  Also Miller will also have to rewrite their Gas Metal Arc Welding manual.  Wow.  That could keep you busy for some time into the future.Answers to the above questions would surely help me better understand what you base your responses on.Thanks in advance.
Reply:Wow. I never thought my thread would be taken so far.  All of this information back and forth is VERY educational.  I LOVE IT!!!!  I truly thank all of you for that.  DDA52, I believe you are correct.  My question has been satisfactorily answered.  I have also come away pondering more questions (which is a great thing!!!).  Thanks again to everyone who participated in this discussion.  It was not my intention to instigate any confrontations or flaming.  Criticism can be a great thing at learning new things.  Now lets bury the hatchet with a round of beers!!!   (I could only post 6 smilies, so some of you will have to share.  )Oh, I almost forgot....    (one for Zap  )***Stick welding like, woah.***
Reply:Can't we all just get along? (as I put on my purple dinosaur costume)Originally Posted by SundownIIIReddoggoose,Since many of your posts/opinions seem to go against conventional field wisdom and generally accepted practice I'd like to ask a few questions so I can better understand where you're coming from.What degree does a "welding engineer" actually hold?  The reason I ask is because my BS is in Civil Engineering and MS is in Industrial Engineering.  Both are commonly recognized degrees in any engineering school in the country.  I have never heard of a BS in "Welding Engineering".  I certainly hope that this doesn't fall into a similar category as a "Sanitary Engineer, AKA Garbage Collector".What school did you graduate from and when?What is your practical, real world, welding experience and what equipment/processes are you experienced in and to what extent?You seem to have all the AWS codes "right at your fingertips".  What company do you currently work for and what is your job description?It would seem that a person with your "extensive knowledge" would be highly sought after by companies such as Miller and Hobart.  After all, it would appear that they do need to rewrite all their Mig Owner's Manuals cautioning owners against using short circuit transfer to weld aluminum.  I guess both Miller and Hobart will just have to redo all their door chart welding parameters as well.  Also Miller will also have to rewrite their Gas Metal Arc Welding manual.  Wow.  That could keep you busy for some time into the future.Answers to the above questions would surely help me better understand what you base your responses on.Thanks in advance.
Reply:Fellas - agree to disagree or take it to PM's. This thread has reached it's end.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com