Arc Burn 101

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I suspect I could get away with calling myself the resident expert on arc burn so I would like to share a few thoughts with you on this subject. A few days ago I was welding in a full spray [800 ipm @ 32.5 volts] and had to smile at the thought of my post a few days ago. The thought being, I'm glad I'm covered up. For you not familar with spray arc I'll offer an explanation. In mig welding there are three ways to transfer wire to the weld puddle.The most common being short circuit type transfer. The second is globular type and the third is spray type. In a spray arc transfer the wire has melted before it reaches the weld puddle. The distance the melted wire will travel varies relative to wire speed and volts.1/16 to 3/16 of an inch is common.This process requires high wire speed and high voltage which generates tremendous amounts of heat. The weld print called for 18 inches of weld .500 [1/2 inch] wide. It was taking approx. 36 seconds to deposit this weld. During the weld process a person might think they were standing next to a wood burning stove. The point being, any exposed skin will suffer severe arc burn almost immediately when welding at these elevated tempertures.We are issued the green welding jackets made by Tillman. These will began to fade within 15 or 20 min.due to the high amounts of UV being emited. The medical profession says this is a sure highway to skin cancer.I hope this note will encourage you to cover up while welding. ....................PS I'm sure a more in depth explanation of these welding processes can be found online.t
Reply:Timely thread.  I've done a lot of welding over the last three days.  I usually do not where gloves.  Last night I notices my hands.  The looked like they belonged to a 90 year old person. They appear better today.  I am also forcing myself to keep my gloves on today.Excessive amounts of tacking w/o face sheild causes my face to peel...a habit remedied by a/d helmet. I have more arc burn problems when I mig or tig than with stick.Side note:Anybody have suggestion for comfortable gloves.???
Reply:for a realy good arc burn try spray on S/S  i had a guy working for me wen we got some S/S in not much a days worth of welding i told him he needed to get some sleves and button up his shirt ,he did not the next day he came in burnt to a crisp and sick as a dog before he wen back home to heal he told me i was right ChuckASME Pressure Vessel welder
Reply:Chopper,is that becasue of the reflectivity of the S/S surface?Smithboy...if it ain't broke, you ain't tryin'.
Reply:When i was an apprentice welder, i got stuck on a spray arc job,doing one side ( the top side ) of roundabouts ( submarine pressure hull frames ) 1/16 wire ,330 amps , 32 volts . i could not hack it for 2 minutes. one guy, only one -out of 1200 welders in shop could do it really good. he'd stay at it 20 minutes straight , then take a 10 minute break, his FULL leathers dripping with sweat . Nobody messed with him . this was on hy-80 steel. He could back -arc the top side of the frame , 4 guys stick (110-18 ) the underside,& weld the top side , take his breaks , & stay ahead of the 4 guys stick welding  !
Reply:Spray arc certainly does produce a great deal of heat.  I developed the bad habit of keeping my supporting hand very close to the nozzle.  The first time I ever tried spray corrected that habit and also charred a nice new pair of Tillman gloves.I've heard of water-cooled MIG torches, but have never actually seen one.  I wonder if anyone here has used one?-Heath
Reply:wow this sounds really cool... i've never seen it done but i really dont think i'm gonna do it any time in the near future anybody got pics of this process?...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:Originally Posted by zapsteranybody got pics of this process?
Reply:Originally Posted by zapsterwow this sounds really cool... i've never seen it done but i really dont think i'm gonna do it any time in the near future anybody got pics of this process?...zap!
Reply:Originally Posted by halbrittThe best way to check it out is to try it for yourself because it's really, really neat.  You could try it with 100% argon if you have that around.  The results might not be optimal, but you'd get a sample of what it's like.  The frying bacon sounds is replaced with a hiss, travel speed is greater than you would expect and there's little time or need to do any kind of torch manipulation (weave).  Generally you're left with a very pretty, spatter-free weld with great penetration.  If you're not careful, you're also left with a smoking glove and a melted tip.
Reply:Originally Posted by halbrittI've heard of water-cooled MIG torches, but have never actually seen one.  I wonder if anyone here has used one?
Reply:I found a picture I cropped to provide privacy to the company as well as trade secrets... If you believe that....:'))  This is a simple boom.  we also have a mid jointed boom that reaches farther.  the power unit is on the left and mounted on the column is the small water cooler.  On the end of the boom is a LED display with a full menu that can drive you crazy with multiple menus.  We run off the 500 pound drums of wire and a manifold system for gas mix Attached Images
Reply:My post ( #5 )  that gun was water cooled . forgot to mention that . even  so;  hotter'n  hadies . it had about a 30 gallon water tank , & it would be almost boiling in a short time .
Reply:I was using a Powerwave 455, .035 wire,98-2,@about50cfh. It has water cooled capabilty but we don't use it. Don't know why.................. I've done a lot of tig wearing a dark tshirt, glove on torch hand only. Low amp stuff. Does not seem to be much problem with arc burn. A little where the shirt sleeve ends. I wear a Wrangler denium long sleeve shirt now. You can find them at Tractor Supply.
Reply:Originally Posted by Roy HodgesWhen i was an apprentice welder, i got stuck on a spray arc job,doing one side ( the top side ) of roundabouts ( submarine pressure hull frames ) 1/16 wire ,330 amps , 32 volts . i could not hack it for 2 minutes. one guy, only one -out of 1200 welders in shop could do it really good. he'd stay at it 20 minutes straight , then take a 10 minute break, his FULL leathers dripping with sweat . Nobody messed with him . this was on hy-80 steel. He could back -arc the top side of the frame , 4 guys stick (110-18 ) the underside,& weld the top side , take his breaks , & stay ahead of the 4 guys stick welding  !
Reply:Originally Posted by lotechmanWe have a couple of Lincoln Powerwave 600 's with booms and water cooled guns.  Once you get to 300 to 350 inches per minute on .045 wire regular air cooled guns don't last.  Our booms run .052 metal cored wire.  The gun lead is a bit larger but you do get used to it.   A nice feature is the toggle feature.  You can set it so that you pull the trigger once to start and when you want to stop you pull it again.  It allows you to move your hand even further back away from the action.   We have installed an option on the boom.  There is a small unit that shuts off the trigger current and stops the welding if there is no water running through the gun.  It saves the gun lead which runs around 800 dollars Canadian.  I will look around to see if I have any shop pics of these units.
Reply:Originally Posted by smithboyChopper,is that becasue of the reflectivity of the S/S surface?
Reply:heath,If you are talking about the same gun I am thinking of, I think those guns are rated at 400 amps with 100% co2.  Make sure to check the amp rating with different gases, cause it's lower for mixes (and obviously flux core).Smithboy...if it ain't broke, you ain't tryin'.
Reply:I "did my time " at Mare Island . all together , about 16 years . And, I live in the Beautiful Napa Valley . ( California  )