tigging magnesium

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I posted a question a couple of days ago asking how to bend aluminum. Well, it turns out that it may be magnesium. NOW my question is: how do I tell if it is in fact magnesium, and if it is, how do I go about welding it.I know for a fact that the material is not al. because when I tried welding it today, the filler rod looked kind of like it was holding, but one not so hard whack on the table and the pieces broke apart. And at the joint that I was trying to join together crumbled kind of like little grains of fine glitter where the heat was.I heard you could tell if it was magnesium by grinding it and if the sparks were white, it is. Any truth to that?Thanks fellas.
Reply:It may be possible that the material is one of the 7XXX series, of which, many are not weldable. If you are pretty sure that it is mag then, one quick way to distinguish between aluminum and magnesium is to file of some shavings and light them on fire. If it's mag then the filings will  burn white, and fast. Another method I have heard of, though I have never personally tried it, is to put battery acid on the filings. Mag will turn black, aluminum will not change.Magnesium will weld very similar to aluminum. Both materials have a passive oxide layer that should be removed prior to welding. If TIG welding use AC. If MIG welding use the usual DCEP polarity. Obviously use magnesium filler metals, and 100% argon gas. Something to keep in mind is that mag has a lower thermal conductivity than aluminum, but has a higher coeffecient of expansion than aluminum. This will make it more prone to distortion than what you would typically see with aluminum.Last edited by reddoggoose; 08-29-2007 at 03:35 PM.Arguing with a Welding Engineer is like wrestling with a pig... after a while you realize the pig likes it
Reply:Thanks for the quick reply. And now that you mentioned it, I didn't have to push the pedal as far down as I would have with al. of the same thickness.I will give the burning the filings a try.BTW, any recommendations on an epoxy-like adhesive that I could use should it so happen that I will not be able to weld this?Last edited by rajun asian; 08-29-2007 at 04:25 PM.
Reply:I find that when tig welding magnesium, it gives of a greeish glow.What you might have is "white" or "pot" metal, it is possible to weld this but it is difficult.Just my  opinion, not from a book, just from the road.Howes Welding Inc.www.howesweldinginc.com
Reply:Note, if you do the burn test, do it in a SAFE place!Magnesium burns hot-hot-hot.  And water or other common fire-extinguishing agents will -not- put it out.  (one common emergency fire starter for camping/emergency use is a block of magnesium, you shave off some metal and then hit it with a spark from the built-in 'flint', result is FIRE).Magnesium is a -little- lighter than aluminum (0.0629 lb/in3 for pure mag versus 0.098 lb/in3 for pure al up to .102 lb/in3 for 7075), but their melting points are pretty close (1200F for pure mag, 1220F for pure aluminum).The coefficient of thermal expansion of aluminum and magnesium are pretty darn close (15.2 micro-inch/inch-F for pure al versus 16.4 micro-inch/inch-F for pure mag, over a range up to 900F or so), but the magnesium takes about 20% more heat to raise its temp the same amount as the aluminum.  The thermal conductivities differ by about 30% pure-vs-pure, and depending on what your mag alloy may be it could be a 50% difference.Are you dealing with cast or extruded metal?I'd probably compare weight, then do the shavings fire test.  Light and burns, it's magnesium.  Otherwise, it's probably an aluminum alloy.To put it together, maybe bolt or rivet it.And the 7xxx sereies aluminum alloys are generally unweldable.
Reply:Well it depends...never done it myself but I´ve heard that is very dangerous to weld it...Don´t know your capacity but even pro´s here said don´t do it.What´s the piece?My Babies: HF Drill pressHF Pipe Bender3   4.5" Black and Decker angle grindersLincoln Electric PROMIG 175that´s it!
Reply:Good topic, I've got a crankcase cover for a motorcycle that may or may not be magnesium and it needs some welding done to it.  I didn't know where to start.
Reply:Originally Posted by elvergonWell it depends...never done it myself but I´ve heard that is very dangerous to weld it...Don´t know your capacity but even pro´s here said don´t do it.What´s the piece?
Reply:Save yourself time, money and possibly burning down the block - Momo sells a steering wheel similar to what your desire - $200. http://www.modacar.com/products/Hond...ng+Wheels.htmlJohn -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Along the same lines, if you decide to weld it, you can also apply a few drops of Duzall Flux to a clean piece of the job in question.If it is indeed Magnesium, the flux will rapidly bubble and turn black. If it is Aluminium, the flux will just simply sit there and do nothing.Further information on welding magnesium: http://www.weldwell.co.nz/advice/whi...iun_advice.htm (yes, the webmaster spelled it wrong but the link works)John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Originally Posted by MicroZoneSave yourself time, money and possibly burning down the block - Momo sells a steering wheel similar to what your desire - $200. http://www.modacar.com/products/Hond...ng+Wheels.html
Reply:Originally Posted by MicroZoneAlong the same lines, if you decide to weld it, you can also apply a few drops of Duzall Flux to a clean piece of the job in question.If it is indeed Magnesium, the flux will rapidly bubble and turn black. If it is Aluminium, the flux will just simply sit there and do nothing.Further information on welding magnesium: http://www.weldwell.co.nz/advice/whi...iun_advice.htm (yes, the webmaster spelled it wrong but the link works)
Reply:Originally Posted by MicroZoneSave yourself time, money and possibly burning down the block - Momo sells a steering wheel similar to what your desire - $200. http://www.modacar.com/products/Hond...ng+Wheels.html
Reply:Remember one thing here..Have a deep hold dug somewhere to bury it if it catches fire..It will not go out with water.. Or a fire bottle..Don't bother even trying.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Everyone keeps mentioning that Magnesium can not be put out with water...Good point! . .. ... However, what has not been mentioned is this.When I was in school for Aviation we were showed a film on how to deal with aircraft fires. Part of the film showed a wheel fire caused by bad brakes (some aircraft wheels are made of magnesium). They used water on the fire as a demonstration of what not to do and the fired increased in intensity about ten fold. DON'T EVER PUT WATER ON A MAGNESIUM FIRE!   Period Washman
Reply:Originally Posted by WashmanEveryone keeps mentioning that Magnesium can not be put out with water...Good point! . .. ... However, what has not been mentioned is this.When I was in school for Aviation we were showed a film on how to deal with aircraft fires. Part of the film showed a wheel fire caused by bad brakes (some aircraft wheels are made of magnesium). They used water on the fire as a demonstration of what not to do and the fired increased in intensity about ten fold. DON'T EVER PUT WATER ON A MAGNESIUM FIRE!   Period Washman
Reply:I've done a fair bit of Magnesium welding and it is totally different to aluminium to weld. It gives off a very dirty greenish haze and the impression is that the weld will look like cr@p but often that's not the case and it looks fine.You need less amps, more cleaning action on the AC balance and if you have an inverter machine run the Hertz frequency around 80Hz, also Zirconated electrodes.The most critical part by far is cleaning off the oxide and this needs to done by a die grinder using a high speed steel or carbide cutter. You will notice it doesn't clog the cutter like Aluminium and the Mag finish under the oxide comes up much shinier than Aluminium as well.Don't bother using a "gas lens" the arc is so dirty you stand a good chance to cover the gas lens with contaminants. We use AZ92A filler, it seems to be a pretty good match for most of the Mag repairs we do, particularly Mag castings.Regards Andrew.
Reply:Originally Posted by WashmanThey used water on the fire as a demonstration of what not to do and the fired increased in intensity about ten fold. DON'T EVER PUT WATER ON A MAGNESIUM FIRE!   Period
Reply:How do you prevent it from catching fire in the first place if you are welding on it?
Reply:hey all,i find it strange (actually, hard to believe) that honda would go to the trouble and expense of using mag for a steering wheel. an unweldable Al alloy makes more sense to me but anyways...while the fire risk with mag is very real it's actually quite hard to ignite a large hunk of the stuff- it's simply too good a heat conductor. the real danger lies in swarf/shavings- cleaning up ALL swarf is very important!as said water and a mag fire= a bigger fire or even an explosion!in the absence of a class D fire extinguiser a bucket of sand on hand is a good ideadon't know if SIFBRONZE products are available outside the UK but might be worth a google. they deal mainly with brazing products but sell small packets of speciality/expensive fillers- 6 rod packs of silver solder AND magnesium filler for example. very useful for one off jobs
Reply:Originally Posted by WelderBoyHow do you prevent it from catching fire in the first place if you are welding on it?
Reply:[QUOTE=hotrodder]hey all,i find it strange (actually, hard to believe) that honda would go to the trouble and expense of using mag for a steering wheel. It's true. It is supposed to give a better steering feel. Nissan also used a mag. steering wheel core in their 350Z.Also, thanks for the heads up on obtaining filler rod.
Reply:Originally Posted by awill4x4I've done a fair bit of Magnesium welding and it is totally different to aluminium to weld. It gives off a very dirty greenish haze and the impression is that the weld will look like cr@p but often that's not the case and it looks fine.You need less amps, more cleaning action on the AC balance and if you have an inverter machine run the Hertz frequency around 80Hz, also Zirconated electrodes.The most critical part by far is cleaning off the oxide and this needs to done by a die grinder using a high speed steel or carbide cutter. You will notice it doesn't clog the cutter like Aluminium and the Mag finish under the oxide comes up much shinier than Aluminium as well.Don't bother using a "gas lens" the arc is so dirty you stand a good chance to cover the gas lens with contaminants. We use AZ92A filler, it seems to be a pretty good match for most of the Mag repairs we do, particularly Mag castings.Regards Andrew.
Reply:I just wanna once again thank everyone for all of their great advice and words of precaution. There are so many knowledgeable welders on this site and I am very happy to have access to this wealth of knowledge. Hopefully I'll be able to get this project completed in the near future. And  get it done safely as well.
Reply:Originally Posted by rajun asianThanks for the write-up. That was really what I was hoping for. BTW, the only tungstens we have are 2% thor. and ceriated. Think the ceriated will be ok?Seems to me that a steering wheel made of mag would be something a mfg. would never do because of liability..ie fire in an accident. Not to mention how easily it breaks when stessed. Al-Mag would be more like it.In the early 60's cars tried using mag on wheels(pontiac I believe) and they proved dangerous enuff in the case of fire but inside by your chest...wouldn't that be nice if you were pinned into a wrecked car??I've welded it and the argon keeps it from burning.Myself I would try tigging a small section with 5356 on just the edge and see how it fused...if it jumps right on it then it prolly ain't mag and you'll know after it cools because it sometimes cracks loose on it's own afterwards. BTDTSome mag parts say so right on them BTWMiller Dynasty 700Miller 350P with Aluma-pro push-pullMiller 280 Dynasty with expansion card Dynasty 200 DXMigMax 215 Enuff power and hand tools to create one of anything..... but mass produce nothing!!!
Reply:I heard GM used a lot of magnesium in their steering columns.  I saw a video of some fire fighters demonstrating what happens when you put a shot of water on the dash.  It doesn't explode or anything, but it makes a pretty big flash.
Reply:Chevy still uses Magnesium in their wheels, it was a big dollar option starting in 1998 for the new C5 Corvette...about $3,000. The import manufacturers are using a mag mix on wheels because of its ability to give more in a crash scenario. I thought it was backward thinking as well for them to use it in steering wheels but I guess quite a few manufacturers are doing it. John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Sounds like an awsum place for a bloodsucking lawyer to find his niche'....let's just burn out the drivers chest cavity!!I think benefit wise with all the carbon fiber technology and all they are splitting hairs...IMOMiller Dynasty 700Miller 350P with Aluma-pro push-pullMiller 280 Dynasty with expansion card Dynasty 200 DXMigMax 215 Enuff power and hand tools to create one of anything..... but mass produce nothing!!!
Reply:mag parts on a car do not increase the chance of a car fire! as i said before a solid chunk of mag is not easy to ignite- any mag fire will only be started by another fire that has gotten well out of control (seen plenty of totally burnt out air-cooled VWs- not one of them had got hot enough to ignite the mag engine/trans case though). any poor soul trapped in a car fire would be long dead before the mag caught light- dead is dead, all the mag would do is make it harder to extinguish the fireFusionKing, keep it quite! lawyers cause enough grief without you giving them ideas  MicroZone, wouldn't have thought a mag casting will 'give' much more than an Al casting. a forged mag wheel though, completely different animal
Reply:HR - this is what I found on the web regarding manufacturing of the steering wheels: "...steering wheel formed of a magnesium based alloy AM 50B. Steering wheels composed of this alloy offer greater elongation while maintaining high strength values. Such steering wheels are strong yet safer than steering wheels formed of other prior magnesium alloys."John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:found a couple of articles from that MicroZonecouldn't find any info on the actual alloy composition though (beyond it being a casting alloy). the Dow Chemical Co was listed as a supplier but curiously their website is totally devoid of any mention of it
Reply:Ya, it's probably some type of proprietary mix.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:OK I can add something here. I have welded some magnesium before and the fire hazard wasn't with the weld puddle but the filler material. If you get the filler too close to the arc and it balls up, don't just flip it off cause that molten ball will light up like a sparkler.Don't talk about it, Just do it!
Reply:Cool!!...can't wait to give that a try!! Miller Dynasty 700Miller 350P with Aluma-pro push-pullMiller 280 Dynasty with expansion card Dynasty 200 DXMigMax 215 Enuff power and hand tools to create one of anything..... but mass produce nothing!!!
Reply:Just wanna let you guys know I was able to track down some filler. I went to the local weld supply store and they said they'd have to order some which would take about 4 weeks to get AND it would cost about $75 for a pound. So I asked if they knew of any welding shops close by that they may have sold some rod to. They pointed me to "Bill's Welding" which was about 1 1/2 miles away. I drove there, told the man what I needed, and he hooked me up with 5 lengths of 3/32 for $10. That's probably way more than I would ever need. So I bull$hitted with the guy for a little bit and just threw out "so you guys looking to hire anyone?" And he said "Uhhh, yeah". So I'm dropping off a resume' on Monday. They do all kinds of stuff there too. They weld titanium also. I'm getting pretty excited.
Reply:Hey - that's a good deal, you found a few pieces of titanium and possibly might have a job. Nothing wrong with that. But I gotta say - I told you so - the [Ti] wire is EXPENSIVE. John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Originally Posted by Vicoordon't just flip it off cause that molten ball will light up like a sparkler.
Reply:My dad wanted me to weld an unavailable steering column, sure enough it was mag. I passed on the job, I was unsure about it, but then someone else wanted me to weld some mag. the next week, and it was pretty easy...Miller Dynasty 200 DX(love it!, well I did, now its a paperweight)Miller fixed it, haven't used it much yet $2900 warranty Miller 210 Thermal Arc UltraFlex 350Cobra Push-Pull Wire feedLots of other things
Reply:magnesium will foam some if white vineger is put on it.
Reply:Yeah I think it should be mentioned that it burns BRIGHT!  Like keep your welding helmet on bright if you want to deal with it.  You can't really look at it with your naked eyes.  So if you do light something up, I'd just dump it someplace where no one can get hurt and let it burn..
Reply:Thought I would add a lil tidbit here.Its not the argon that keeps the metal from catching ablaze, think about whats going on with the backside of your weld. There is a good temperature difference between melting temperature and ignition temperature.Magnesium was torch welded for years, and in certain fields still is. I mosty weld magnesium sheet with the torch for induction systems, works very well.
Reply:Originally Posted by rajun asianI posted a question a couple of days ago asking how to bend aluminum. Well, it turns out that it may be magnesium. NOW my question is: how do I tell if it is in fact magnesium, and if it is, how do I go about welding it.I know for a fact that the material is not al. because when I tried welding it today, the filler rod looked kind of like it was holding, but one not so hard whack on the table and the pieces broke apart. And at the joint that I was trying to join together crumbled kind of like little grains of fine glitter where the heat was.I heard you could tell if it was magnesium by grinding it and if the sparks were white, it is. Any truth to that?Thanks fellas.
Reply:I will add that you have no threat of fire when just welding mag. Shavings will quickly ignite, but to catch a piece of it on fire from TIG welding just doesn't happen unless you have magnesium grinding dust or flakes ignite in the viscinity.