Can you answer this??

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How is it possible to weld overhead (upside down)?... the molten metal is defying gravity.What is it that makes the molten metal from the wire (MIG) jump UPWARDS and onto the workpiece??
Reply:No problem here. You need to read the puddle as you are doing it. Not a Pro instructor so hard to explain. Try it an some coupons.www.tjsperformance.comDynasty 300 DXHTP 240HTP Microcut 380Hyperthem 85JD2 Hyd Bender and HF Hyd Ring Roller all in one =(Frankenbender)Bpt. Mill/DRO4' x 8' CNC Plasma TableInstagram: tjsperformanceYT: TJS Welding and Fabrication
Reply:Surface tension prevents the molten metal from dripping down.
Reply:Originally Posted by Pete.S.Surface tension prevents the molten metal from dripping down.
Reply:surface tension and arc force (basically a plasma jet that sprays the molten metal from the tip of the rod), with a quick freeze rod it hardens before gravity can really work on it. Nothing magical about it, it just works
Reply:So u can't use globular transfer when welding overhead?Are u sure its "arc force"??.  I thought it would have more to do with electro-magnetism.
Reply:Is "arc force" a kinetic force or a magnetic force?
Reply:PULSED (axial/spray transfer) MIG is used in all positions. 1, 2, 3, 4, and 5.  Vertical UP w/ pulsed spray is rock'n!"Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
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Reply:Skill man !!
Reply:How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does.
Reply:Arc force is a function of arc voltage, therefore I would assume it is electro-magnetic or in reality a plasma jet created by through electro-magnetic means that creates a kenetic force by "blowing" the molten metal at the weld joint.
Reply:Originally Posted by rdop2001How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does.
Reply:Originally Posted by ironmangqArc force is a function of arc voltage, therefore I would assume it is electro-magnetic or in reality a plasma jet created by through electro-magnetic means that creates a kenetic force by "blowing" the molten metal at the weld joint.
Reply:" You're pretty much saying that its both magnetic and kinetic. It can't be both."Yes, it can be a bit of both! Electromagnetic forces help "transfer" the molten/melting metal across the gap between electrode tip and the base metal being welded.  Kinetic principles apply also because as the molten/melting metal is traveling across the gap, it develops a bit of inertia (because it is mass in motion) and as it strikes the puddle, it tends to dissipate that inertia into the puddle.  The impacting action of the deposit material tends to help keep the puddle "up". This is analogous to using a garden hose to sluice a volume of water upward through an inclined or vertical chute.  The inertia of the water in the stream impels water that has already struck the chute to move ahead in such a way that you are sort of "sweeping" the accumulation of water using the inertia of the water stream like a broom.  Similarly, the inertia of the mass of metal in the arc stream aids in keeping the puddle suspended.
Reply:Originally Posted by walkerweld" You're pretty much saying that its both magnetic and kinetic. It can't be both."Yes, it can be a bit of both! Electromagnetic forces help "transfer" the molten/melting metal across the gap between electrode tip and the base metal being welded.  Kinetic principles apply also because as the molten/melting metal is traveling across the gap, it develops a bit of inertia (because it is mass in motion) and as it strikes the puddle, it tends to dissipate that inertia into the puddle.  The impacting action of the deposit material tends to help keep the puddle "up". This is analogous to using a garden hose to sluice a volume of water upward through an inclined or vertical chute.  The inertia of the water in the stream impels water that has already struck the chute to move ahead in such a way that you are sort of "sweeping" the accumulation of water using the inertia of the water stream like a broom.  Similarly, the inertia of the mass of metal in the arc stream aids in keeping the puddle suspended.
Reply:Originally Posted by rdop2001How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does.
Reply:The "arc force" is electro-magnetic.
Reply:The force that propels the molten metal is Electromotive Force. EMF.  This is the same force that enables electron flow in a circuit.  An arc is a circuit.  The EMF carrying electron flow across the gap (arc length) picks up and transports some atoms of molten metal and those atoms enable some other atoms to tag along (due to cohesive attraction,m i.e. surface tension).The ability for the atoms to hitch a ride on the EMF is what arc welding is all about.  And DC reverse polarity does this best. And remember, DC reverse (electrode positive) means that the electrons in the circuit are moving from the base metal to the electrode.So how does that cause the atoms to be moved from the electrode toward the base metal?It is because in the attempt for the electrons to move from the base metal toward the electrode, each electron is acting like a member of  a "bucket brigade" passing atoms of metal to the electron behind it, as it in turn is reaching for a "bucket" of molten metal from the electron ahead of it.  As the electrons flow across the gap from base to electrode, they cause a flow of molten metal to move in the opposite direction, and inertia is developed in the process.  As stated before, the transfer process is a combination of cohesion (surface tension) and electromagnetism.  DC straight polarity welding depends almost entirely on surface tension to affect metal transfer, with a little help from the heat flow (another form of energy).  What you want to argue about now?Last edited by walkerweld; 09-13-2013 at 01:37 PM.
Reply:So is electromotive force the exact same thing as magnetic force??
Reply:From a search..."Electromotive force, or emf, is better described as the total voltage in an electric circuit generated by the source or battery. Emf is not a physical force......In simple words, it may be stated as electromotive force is the maximum voltage that can be attained by a specific circuit."I was then referred to "Faraday's Law", which states:"Faraday's law of induction is a basic law of electromagnetism predicting how a magnetic field will interact with an electric circuit to produce an electromotive force (EMF). It is the fundamental operating principle of transformers, inductors, and many types of electrical motors, generators and solenoids."So I would say no. One is not the other, but one results from the other. But I'm no physicist.Last edited by akabadnews; 09-14-2013 at 05:59 AM.
Reply:So its much closer to being a magnetic force than kinetic force.  I think we've settled it.
Reply:Skill. You get to a point where your overhead resembles flat. Long-arcing cuases molten drips, and some gnarley chest scars. Ask me how I know. Position and comfort are huge in acheiving quality overhead welds. If you get shaky, it will show 10 fold. Surface tension on a stable puddle is what keeps it up, correct arc gaps are what keep it stable.Lincoln Power MIG 210 MP ( boat anchor )Lincoln Weld-Pac 100 HDHobart IronMan 230Cutmaster 42Jackson NexGenSumner Ultra ClampsDWM120