Applying cold water to a weld ?

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I am going to weld some 1/8" material ,and want to keep the heat down as much as possible.If I apply water after each weld, will this work?Now the other thing is I do not want the part to warp because of the welding.If I apply water this will cool the metal down rapidly,this will cause warping right?Little confused here guys, thanks. I am welding on some truck trailing arms (65 chevy),the are a I beam shape(two U channels spot welded back to back) ,and about 5' long.Last edited by Casarez; 12-26-2005 at 02:45 PM.
Reply:I would not use water. This cools down the weld too soon and could cause failure to the weld (it could crack). If you have a compressor, use air to cool it down. As someone stated in another thread, use aluminum as a heat sink. I welded some control arms for my neighbors El Camino. I alternated the bead and welded about 1/2 inch at a time, with no other cooling method. Oh yeah, I did all four, so I welded one, went to another, and so on. This worked out pretty good as it distorted very little. Only one bushing gave us problems going in and the went back on the Camino with no problems.
Reply:A small pump spray bottle works nicely to cool things.  Don't spray until the red has disappeared.  Skip welding and doing short beads is a better way to go.  You don't know the alloy nature of suspension arms.  It is better to take a bit more time and let each short weld air cool.  It is wise to only spray cool body panel material.
Reply:Might want to try clamping on some thicker pieces of metal to act as a heat sink.
Reply:a alternate to a heat sink is to use wet rags. drench the rags in water, ring them out and wipe the metal. A heat sink of some type is obviously a better choice
Reply:ive used water...  but only on non critical jobs...  basically if it could break and someone get hurt its critical    just my two centsIF it Catches...Let it Burn
Reply:I know little about alloys and metallurgy, but one side effect of water cooling a weld is that it makes the weld much more hard and much more brittle right away.  If you need to do any cutting or grinding later, it will take a lot more effort (and wasting cutting wheels, etc.) on a weld that has been water cooled.  This has just been my experience though.  If my life depended on it, I could not explain the science behind it.
Reply:The term is known as "quenching" and it's a bad idea.  It will harden carbon steel and make the weld prone to cracking without proper tempering.  It will also increase the likelihood of deformation.As suggested, you could use a heat-sink or damp rags.  Just make sure that the weld area doesn't get wet.  There is a product called heat-stop paste that's used to dissipate heat.  I know that Brownell's sells it (a gunsmith supply) and I think I've seen it in welding shops.  It's used to minimize the impact to heat-treatment for something like welding bolt handles onto a rifle bolt.-Heath
Reply:I've used square copper bars (say 6" long, 1X1") as heatsinks for sheet metal work. Works rather well.
Reply:Originally Posted by halbrittThe term is known as "quenching" and it's a bad idea.  It will harden carbon steel and make the weld prone to cracking without proper tempering.  It will also increase the likelihood of deformation.As suggested, you could use a heat-sink or damp rags.  Just make sure that the weld area doesn't get wet.  There is a product called heat-stop paste that's used to dissipate heat.  I know that Brownell's sells it (a gunsmith supply) and I think I've seen it in welding shops.  It's used to minimize the impact to heat-treatment for something like welding bolt handles onto a rifle bolt.
Reply:Grr in my last post I used a word to define itself.  Tempering would be associated with bringing a tool or whatever to a hardness desirable to the needs of that tool  sorryIF it Catches...Let it Burn
Reply:Body shops also use the paste a lot that "halbritt" is talking about. I have not used it but a friend of mine ownes a body ahop and swear by it. He claims he can heat saysome round stock to bend. He can get it cherry red but 6" away where he applied the paste he touch it with his bare hand.Yes I can tack it for you.    I know that won't hold but that is what you asked me to do.  Millermatic 350P XR Aluma-Pro push/pullMillermatic 185/spool gunMiller Dialarc 250 HF Water cooledThermal Dynamics Plasma
Reply:Originally Posted by TxRedneckActually heath if you want to get technical the term for this would be normalizing because youre bringing the steel back to its normal state.  Tempering is usually associated with bringing the steel to a desired temper, such as for a knife or a chisel or other tool.
Reply:Halbritt hit it on the head on his last post. I learned exactly what he said in metallurgy.When heat treating a metal or jsut plain heating you take the metal from a Pearlitic state and heat it up to an Austenitic state. To harden a metal you need to heat the metal to 50*-100* above the A3 Critical line on an Iron-Carbon phase diagram. Hold it at that temp for 1 hr per in. thickness.Then quench.It was mentioned before but quenchants can be anything from air which is the slowest to Caustic(CaCl2+H2O) being the fastest.Quenchants:- Air- Oil (Mineral)- Oil (Synthetic/Polymer)- Water (Still)- Water (Agitated)- Brine (Salt+Water)- Caustic (CaCl2+H2O)The quenchants are listed there in order of severity. The higher the severity the faster it quenches.Once you have returned the metal to Room Temp. the metal is in a martensitic state which is metastable.Metastable- When a material tries to change back to its original form.Martensite is very hard, yet very very brittle, so it needs to be tempered.To see how hot you need to heat the metal you can look at a Temper Curve and find the hardness you are looking to achieve, using either a Rockwell B,Rockwell C, or the Brinell hardness scales.The metal will go from Martensite, to Troostite, to Sorbite. Sorbite is the max strength and ductility a metal can have. Troostite is between 450*-750*F and Sorbite is 750*-1300*F.
Reply:i have to add that plane steel with a carbon content of .40 or less will not get hard no matter what you quench it in SA36 is a structural steel it has .26crabon content for toughness it will not get hard from quenching .the angle iron you get from the hardwere store is 1018 the 18 is the carbon content .18 so it wont get hard from quenching.you need the steel to have .40 poinst of carbon or more or you have to addother allloys to change it to make it hardenable .and a hardenable steel has to be heated to it critcal temp (nonmagnetic)for simple steels then quenched to cool it fast enuff to pass from austenite to martensite .haveing typed all that is not a good idea to quench a welded part if it stillred hot it can couese the weld to crack but you can cool it with air or a squrtbottle of water by misting this will cool it faster then just letting it set in still airbut not so fast as to crack the weld if its cast iron you whant to keep it hot and let it cool very slowlyChuckASME Pressure Vessel welder
Reply:We use a water mist to straighten pipe that has drawed out of line while welding. Use a spray bottle and spray a mist on the high side to pull it back in line.
Reply:That's clever.-Heath
Reply:I use water to bend molded cap rail (handrail).  When I have to form a long natural curve,  I will heat the outside of the rail causing expansion and cool the inside with water causing contraction.  Eliminates kinks on the inside. Works well.
Reply:I had welded up a patch on a oil pan on a 2002 7.3 diesel about 3 months ago. We drained the oil out and I started to it. I had the problem that the pan was so thin in some spots that I would burn through and laying on my back really didn't help much. We ended up filling the pan with 3 gallons of water and I welded it where it leaked until it stopped dripping. Now it don't look the best but it works.And it has been 3 months and still no leaks and running good.
Reply:lmao thats the funniest danged thing Ive ever heard.  Still, if it works it works.  IF it Catches...Let it Burn
Reply:>"i have to add that plane steel with a carbon content of .40 or less will not get hard no matter what you quench it------ "< It is easily possible to rapidly quench something like *thin* 1030 in brine or cold water and it will transform to martensite.  You'll end up with a hardness of Rc50!Even a 1/2" dia. bar will harden when quenched fast.
Reply:ok the point is it still has to have enuff carbon or alloy be at the right temp and  cooled fast enuff to make it hardenChuckASME Pressure Vessel welder
Reply:oh and i will also add the if you use old bed rails for angle iron its not the same stuff the angle iron that bed rails is made from will hardenChuckASME Pressure Vessel welder
Reply:Here is a link with some basic info on steel carbon content and hardenability.http://www.azom.com/details.asp?ArticleID=400also this sitehttp://www.welding-advisers.com/Weld...loy-steel.html