Cooling welds with water?

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I have been spraying my MIG welds with water so that painted areas a few inches away doesn't smoke..... i have searched around and nowhere does anyone say NOT to do this, but people do mention a lot that you want welds to cool slowly.... Have i ruined all these welds by making them too brittle?I will weld for 5-30 seconds and then cool the entire area down with a spray bottle.I am using a 220v lincoln mig welder on 1/8 and 1/4th inch steel mostly.
Reply:http://en.wikipedia.org/wiki/Metallurgyhttp://www.answers.com/topic/microstructurehttp://www.lexic.us/definition-of/micrographshttp://www.lanl.gov/mst/mst6/index.shtmlhttp://www.eng-tips.com/viewthread.c...77040&page=131http://books.google.com/books?id=hoM...graphs&f=falsehttp://www.meiji.net/metallurgical%20microscopehttp://www.metallurgicalmicroscopes.com/It depends, if the paint is more important than the strength and toughness of the weld, then go right ahead and squirt it. I usually just scrape off the burnt paint then shoot it with primer...after it cools. The paint booth is down the hall.--->City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Yeah that is a 'no-no'.  You lose the ductility your weld, or at least reduces it.  However for cosmetic welds I have done what you have done.    I am sure those links posted above will refer to it as creating a martensitic structure.  What are you welding on?Jay DavisAWS-CWIC-60 Specialty Welding ContractorLoving husband, and father of two boys (
Reply:Originally Posted by Rat9I will weld for 5-30 seconds and then cool the entire area down with a spray bottle.
Reply:I know at school one kid quenched his test coupon and put it in the giant iron worker shear to cut it in half and it broke the blade on the shear.
Reply:I was welding some things on to the side of my jeep frame. I'm guessing this is very soft flexible steel and should NOT be made brittle. How can i fix this? Can re-heating and slow cooling fix it, or am i screwed ?
Reply:ideally you dont wanna be cooling any welds at all they need to be left to cool in their own time or slower! Having said that is it only carbon steel you are quenching? quenching a weld can only lead to bad news - loss of strength within the joint, brittleness, cracking etc........ as for re-heating and slow cooling your attachments i cant see this helping, the damage has already been done, you will be aggravating the heat affected zone heating and cooling an area will only give you more problems. You have essentially hardened the material, might be worth looking into having the work annealed but tbh i dont think it will work. Carbon steel is brittle anyway without the aid of quenching it but i hope this helps
Reply:Originally Posted by Rat9I was welding some things on to the side of my jeep frame. I'm guessing this is very soft flexible steel and should NOT be made brittle. How can i fix this? Can re-heating and slow cooling fix it, or am i screwed ?
Reply:You did not say what material you were welding.If you put water on aluminum it will become very soft.I would not put water on any weldment that had just been welded. Bad idea.It will change the metal.AWS certified welding inspectorAWS certified welder
Reply:I would not put water on any weldment that had just been welded. Bad idea.It will change the metal.AWS certified welding inspectorAWS certified welder
Reply:some whare i was reading about a paste you could apply out side of the weld zone to keep it cool but i dont remember where that was ...After the arc has died the weld remains
Reply:You can brush on Arcair "Protex" original, or "Heat Fence" (I can't remember the maker). They protect a surface from oxidation and spatter. I'm not sure if that would knock down the out-gasing of paint though.Pouring water on a fresh weld is not a good idea...Matt
Reply:I have always cooled thin body panels with a wet rag, was taught to do this back when I was young and using brazing before I had a MIG.  Quenching the body panel shrinks the panel and helps prevent distortion.  I wouldn't quench any structural welds though and as has already been mentioned quenching helps when flame quenching to bend (or straighten) steel.  High carbon steel can be hardened by quenching (ie springs) but must be annealed by re-heating to the proper tempering temperature depending on the use of the steel.  To quench and not temper high carbon steel will leave it brittle and unusable, prone to cracking and fracture."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:So only "pro-fab" says i might not be screwed The metal i was working on was the frame of my jeep btw for those that asked what the material was. I'm not sure what the carbon content is on that steel.
Reply:Its probably mild carbon steel that makes up the frame of your jeep.  Did you weld material onto the frame or did you cut the frame and add into its structure?  Cutting the frame and welding into it and then water quenching is definitely bad and will require allot of work to correct.  Adding onto the frame will be less of a problem but still require work to fix I would assume but to the extent of the damage done and how much is required to fix it I am not sure.
Reply:Unless the metal was over 1300* when you sprayed water on it, it's probably not actually 'quenching' it. Is it changing the grain structure some by spraying water on it? - yes but I doubt it really hurt it. What exactly were you doing to the frame? Please tell me it wasn't chopped in half and you just butt welded it back together or something...
Reply:I've heard of people using a snowball on the back side of sheet metal panels when mig welding to keep the distortion down to a minimum, but not spraying water.
Reply:using the paste or wetrag/ snowball to stop distortion in sheet metal is totaly diffrent then dumping water on a weld.  the wet rag stops the spread of heat not quenching the weld.
Reply:When we to tests in our weld school we quench practice plates, but on test plates to cool things quick we use compressed air.  Doesn't work as fast as water, but it will cool a hot plate down in about 3-5 minutes.  You definitely dont want to quench those welds.  A spray bottle probably wont hurt, but it's not really helping anything."Real power is an arcair hand torch with a piece of 3/4 inch carbon and 1500 amps.  You feel like Zeus throwing a lightning bolt."
Reply:Originally Posted by Rat9So only "pro-fab" says i might not be screwed The metal i was working on was the frame of my jeep btw for those that asked what the material was. I'm not sure what the carbon content is on that steel.
Reply:Originally Posted by ehkneebreeashun...we use compressed air.  Doesn't work as fast as water, but it will cool a hot plate down in about 3-5 minutes.  You definitely dont want to quench those welds.
Reply:Originally Posted by Rat9I have been spraying my MIG welds with water so that painted areas a few inches away doesn't smoke..... i have searched around and nowhere does anyone say NOT to do this, but people do mention a lot that you want welds to cool slowly.... Have i ruined all these welds by making them too brittle?I will weld for 5-30 seconds and then cool the entire area down with a spray bottle.I am using a 220v lincoln mig welder on 1/8 and 1/4th inch steel mostly.
Reply:In all reality, it depends what you are working on.I've done selective quenching in the past for heat shrinking purposes.  it's amazing what you can do with select amounts of water in the right places.
Reply:Originally Posted by Rat9So only "pro-fab" says i might not be screwed The metal i was working on was the frame of my jeep btw for those that asked what the material was. I'm not sure what the carbon content is on that steel.