Help with Tig Welding Aluminum with Miller DX200

admin

Hello all,I am new to the forum and trying to learn how to tig on Aluminum.  I own a Miller Dynasty DX200 and can weld Stainless Steel and Mild Steel, fairly well.  I took a crash course on tig welding class for about $400 and it got me started, but was kind of a rip off.  Since I own a Tig Welder and have some scrap 2.5" aluminum tubes that i use for intercooler piping, I'd like to practice more without paying another $400 class.I recently had a car come in and fabbed up some intercooler piping, but had to send it out to get welded.  I killed me to do that as I could of done it myself, but no matter what I do I can't seem to lay a bead down well.Can someone offer some good advice for me?  Maybe tell me some settings on the machine?  I changed it to AC instead of DC and don't really mess with any of the other settings.Here are some of my problems:The Material Melts or gets eaten up when I try to weld. (I was told to clean the material and brush it with a steel brush first) The When trying to weld it seems like it constantly "spits"  and is not concentrated on one specific area.I have no idea what all the settings are for and where to set them (Pulser, AC Wave, Sync, etc...)I have different size tungstens and just ordered some lenes but don't know which size and kind to use is best.Most of what I would use is about 1/8" thick or so.  I would also like to start doing "end tanks" for intercoolers, but have no idea what thickness it would be yet.Thanks for the advice.  I'd post up some pics, but I don't want everyone just to bag on me.  I just need some general information first then I will give it a try again.Thanks in Advance.
Reply:Start with the 'how-to' guide for welding aluminum on Miller's website.  There's a wealth of information there, just for the asking.  I'm sure Lincoln has a similar guide to welding also.www.millerwelds.comhttp://www.millerwelds.com/education...rticles15.htmlwww.lincolnelectric.comLast edited by A_DAB_will_do; 10-01-2008 at 01:35 PM.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:http://www.millerwelds.com/resources...ur-skills/tig/http://www.millerwelds.com/education/TIGhandbook/and finallylook at section 10.1 of yer Manualhttp://www.millerwelds.com/om/o2240v_mil.pdfEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Shield gas - using straight argon is okay with the Dynasty, but if you can, get some 75% helium/25% argonSet high freq to start only  You don't need continuous high freq in AC with a DynastyACBalance slighly negativeCurrent 100-130, pedal it3/32 diameter tungsten #8 gas lensER4043 filler metalRegards, KbnitI r 2 a perfessional
Reply:Use a STAINLESS steel brush, not carbon steel.  Its important to point that out.Also, don't use a pure tungsten with the inverter machines.  Ceriated is the tungsten of preference.
Reply:You cannot just buy a welding machine and start welding complex weldments.That is like buying a guitar and expect to just walk out on the stage.I played 366 open mikes then got some help and worked for 3 years before I could play rythmn guitar .Then 3 more years with a band before i could lead a band with confidence and play lead guitar.I went to a junior college to study welding for two years. Then worked for 11 years welding before i took the CWI exam. Then welded aircraft parts, sailboat parts and many other projects after that.I am still learning all the time.You have to pay your dues.You seem to be surprised .Last edited by Donald Branscom; 10-01-2008 at 06:21 PM.AWS certified welding inspectorAWS certified welder
Reply:Originally Posted by Donald BranscomYou cannot just buy a welding machine and start welding complex weldments.That is like buying a guitar and expect to just walk out on the stage.I played 366 open mikes then got some help and worked for 3 years before I could play rythmn guitar .Then 3 more years with a band before i could lead a band with confidence and play lead guitar.I went to a junior college to study welding for two years. Then worked for 11 years welding before i took the CWI exam. Then welded aircraft parts, sailboat parts and many other projects after that.I am still learning all the time.You have to pay your dues.You seem to be surprised .
Reply:why not just make ten louder?
Reply:Originally Posted by drivethruboy54why not just make ten louder?
Reply:Dyno Dave, we need some more info from you on your machine settings, and the tungsten you are using, and the gas, and the filler...then we can dial you in a bit better.I have a very similar machine, a Lincoln Invertec. Let me get you pointed in the right direction. Try my settings first, and see if they help you out a bit:These settings are rough, for approximately 1/8" to 3/16" material:1. Set welder to AC tig.2. Pure argon. No 80/20 gas. Set flow to 15CFH. 3. Amps set to 160.4. Weld frequency set to 80.5. Post flow set to 5 seconds.6. Upslope set to .3 second.7. Downslope set to ZERO, or .1 second.8. Start current at 35 amps.9. Finish current at 18 amps.10. 2% Thoriated or Ceriated tungsten for an inverter welder. Average size tungsten, 3/32". Fairly sharp tip, not completely necessary, but it makes starts easier. Be sure to grind tungsten vertically, and not radially or laterally.This will get you ballpark, and you should be able to get some good welds with these settings. Good luck, and remember a few things- Turn on the gas. Clean the aluminum with a SS brush; maybe an acetone wipe. It certainly won't hurt. The tungsten MUST be clean. Carefully grind off any aluminum on it, or cut off that first 1/4" that is skanky. Grind vertically; tungsten tip pointed UP on the wheel. Not sideways. The arc will wander a whole bunch. Smooth with the torch, straight line. Use the pedal to vary amps as you weld, start hard, and modulate the power once you see a good puddle forming.Good luck. Paul.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:Originally Posted by Broccoli1Shoulda just got an AMP that went to 'leven
Reply:Originally Posted by Donald BranscomYou cannot just buy a welding machine and start welding complex weldments.That is like buying a guitar and expect to just walk out on the stage.I played 366 open mikes then got some help and worked for 3 years before I could play rythmn guitar .Then 3 more years with a band before i could lead a band with confidence and play lead guitar.I went to a junior college to study welding for two years. Then worked for 11 years welding before i took the CWI exam. Then welded aircraft parts, sailboat parts and many other projects after that.I am still learning all the time.You have to pay your dues.You seem to be surprised .
Reply:A_DAB_will_do, Thanks for the link I will have to read it and try it out.Broccoli1, great links also.  Thanks.kbnit, thanks for the base settings.  I will have to try it.Supe, thanks for the advice.  I have a stainless steel brush.Donald Branscom, what can I say ready my previous post ^Rojodiablo, that is great information.  I will try the settings.
Reply:Originally Posted by DynoDaveUH, excuse me for asking you for advise or help.  I am not trying to be an expert, I am merely asking for some advise, I am not asking for your approval!The only way anyone is going to get better is to have the equipment and practice!  I don't work in your industry so I don't do it everyday.  I just want to be able to work on my own projects.By the way, you are incorrect!  I bought a machine, and weld Steel and Stainless steel no problem....Congrats. on your certification, I guess that gives you the right to bag on people like me who is trying to learn!
Reply:From AlcoTec"· Before oxides can be removed from aluminum, the metal must be degreased. This is best done with a solvent. Toluene is the best general solvent for this purpose. Acetone is a poor solvent for oils and greases and is less effective than toluene. Chlorinated solvents are also good degreasers but are not recommended for this application because they present environmental problems and their vapors can decompose into toxic or poisonous gases in the presence of heat. Weld joints should be washed with solvent prior to assembly and wiped dry using clean cloth such as cheesecloth. Shop rags should not be used since they contain soaps and other organic compounds from the washing and conditioning processes used to treat them. Do not use compressed air to blow off or to dry solvent cleaned areas since it often contains moisture and oil."Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:DynoDave,Not trying to be difficult but you initial questions didn't seem to come from someone who just spent $400 on a tig welding course.  Think I'd be asking for a rebate.With the Dynasty 200 (inverter) one of the best features you'll find is the ability to vary the cycles (frequency).  As you go up in cycles the arc will become more concentrated/directed.Paul has given some setting for his machine.  I personally don't think they're the best for you at this time given your machine.  When just starting with aluminum, forget the programs and just use the pedal for controlling your amps.  You're going to start hot and back off on the pedal as you progress with the bead.  I'm not an expert on the Dynasty 200 (been using a Sync250 for more years than I care to count) but have spent some time on my buddy's Dynasty 300.Here's some settings I'd recommend.  You'll still have to find those that "you" feel comfortable with"About 150A on machineHiFreq on start onlyBalance Set to about 70AC (obviously)Frequency about 1203/32" 2% Lanthanated Tungsten (Sharpened to point--point 2xdia. of tung) (Tungsten-Direct on e-bay is a good source).Preflow set to about 1 sec.Postflow set to about 12-15 sec (book will tell you 1 sec/10A).  If tungsten shows signs of frosting, increase postflow.Gas lens with 8 cup will help with covering gas.Keep your filler in the covering gas and off the tungsten (easier said than done).  Aluminum filler is "very" subject to the same oxidation as the base metal.I'd recommend 3/32" 4043 filler for starters.  Most compatable.  Holds up to heat better than 5356.  Cannot be anodized though (turns black).  For anodizing use 5356.Clean your base material well with that SS brush.  The oxidation on the surface is probably where your spitting is coming from.  If your cleaning area (beside the bead) is too narrow or non-existant, drop back slightly on your balance (more cleaning).Pulsing may help you develop you dips.  Try 1/PPS, with 60% background amps.After all this and about a year of daily practice, come back and I'll explain the "bump" method for welding anodized aluminum.Enjoy.  Just takes time and patience.  You'll get real good at sharpening tungstens when welding 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.