Flux core Welding cracks

admin

First off let me introduce myself, Im brand new to this forum and have been welding for a good 1.5-2 years mainly at my university (110 volt miller mig welder, millermatic 140 if i remember correctly). I just recently bought my own welder, didnt want to spend much and went with a campbell hausfeld flux/mig 110 volt welder. 4 voltage settings + infinite wire speed control. Wire that came with the machine was garbage, i bought some flux core 0.030" flux wire (lincoln) and it was night and day.Anyways, I was welding a friends oil pan made of sheet metal, maybe 16 gauge but im not certain, off (i thought it was stamped steel) of an ATV yesterday because some cracks formed around the filler tube/other points causing it to leak. I was at the number 2 voltage setting and a wire speed of about 2/10. Heard the nice bacon sizzling sound but welds were cold i think, didnt seem like they penetrated. I tried slowing my travel speed but that made holes in the pan. Turning the voltage down to 1 helped, but it still wasnt perfect. Any tips? In addition, whenever i put down a bead i heard cracking/popping sounds and cracks appeared right next to the bead i just put down. This made me realize it isnt steeland must be high carbon steel or iron, shouldve done a spark test first.When we filled it with fluid it was leaking badly out of all the cracks that formed.Has anyone dealt with something like this before? I read that i should be using a gas tank with thin material, and also heating it up before welding and slowing the cooling rate since its brittle metal. Problem is, i think if i heat it up beforehand i will most certainly blow holes in it.Any advice is much appreciated, and i thank everyone in advance!
Reply:Is the pan magnetic?  If a magnet doesn't stick, what are the chances it's aluminum?  You can't weld aluminum with steel flux cored wire.If the pan is magnetic, and therefore made of steel, did you clean it thoroughly before you started to weld?  If the metal surrounding the crack was coated with oil and grime, then the contamination of the weld is why it cracked.My guess is your pan is really aluminum, which means you're using the wrong tools for the job.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Hi, the welds did stick well so i dont think it could be aluminum, i would know it was aluminum by looking at it. the arc was also similar to when i weld steel. I did clean all areas first with a wire wheel and then with acetone
Reply:Then again, there was a "tube" coming off the pan that was joined to the pan and it did have that aluminum look to it. Wow, you actually maybe right. But the welds stuck to the metal and it the arc was fine, would that still happen if it was aluminum? I would think you would know right away that somethings wrong
Reply:Also, the weld itself didnt crack, just the pan-material right next to it
Reply:did you clean the oil off of the inside of the pan before welding? if not then the problem is weld contamination.clean the inside of the pan with a non greasy solvent, then with a wire wheel on an angle grinder (be sure to ware gloves, saftey glasses and a face shield, bit's of wire coming off of a wire wheel can pierce strait through safety glasses alone)  clean up the inside and outside of the pan where your welding to remove any paint, dirt ect.if it is aluminium you'll get a white residue (aluminium oxide) around the weld, if you have this, then it is aluminium, but chances are if it's a stamped oil pan that it's steel, an aluminium pan would can cast, not stamped.when welding, try to "spot" weld it, ie only weld a very short section at a time leaving about a second between each spot when welding (dont allow each spot to cool completly, just allow the weld metal to freeze before applying another spot) to keep the heat input into the parent metal at a minimum, this will reduce the chances of heat induced cracking common when welding thin material's.Last edited by ttoks; 05-10-2013 at 11:09 AM.
Reply:What atv is it? Post a picture.Are you sure it is not cast iron? Not that you see that much or maybe not at all I would guess magnesium or aluminum.
Reply:If its aluminum, sometimes steel welds appear to stick, but you could hammer them right off.VERY unlikely that an ATV, which is designed to be driven through water and mud all day, would have a steel oil panel.  Dollars to donuts it's Aluminum.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:Thanks for all the responses, im on my phone now but ill try to post a picture later. The pan is completely closed so i wont be able to clean the inside thoroughly, i did however fill it with acetone and swish it around, then with water to get all the flammable stuff out. My friend told me it was an oil pan, but lets call it an oil canister. I asked my friend to put a magnet to it and it did NOT stick, this means the pan is aluminum/magnesium correct? Also, the welds could NOT be hammered off. I hit the with my slag hammer to get the slag off and nothing budged, this is why its hard for me to say the the pan is aluminum. I was going to use my oxy-acetylene mini torch to try to weld it w aluminum rods and see if it stuck today, but my buddy decided to be a no showI will post pics a little later
Reply:I actually could upload it thru my phone, here u go:PS i know the welds are ugly as all hell, i kept having to go back over them filling in holes + it was flux core
Reply:looking at how it's formed, it looks like pressed steel in shape, it's possible that it's stainless of some kind (magnet's won't stick to most form's of stainless) but also possible it's cast aluminium, easier way to tell is clean the paint off the outside and see what colour it is, pale grey is aluminium, deep grey is low carbon steel, shiny gray is stainless.Last edited by ttoks; 05-11-2013 at 07:28 PM.
Reply:Originally Posted by ride5150Thanks for all the responses, im on my phone now but ill try to post a picture later. The pan is completely closed so i wont be able to clean the inside thoroughly, i did however fill it with acetone and swish it around, then with water to get all the flammable stuff out. My friend told me it was an oil pan, but lets call it an oil canister. I asked my friend to put a magnet to it and it did NOT stick, this means the pan is aluminum/magnesium correct? Also, the welds could NOT be hammered off. I hit the with my slag hammer to get the slag off and nothing budged, this is why its hard for me to say the the pan is aluminum. I was going to use my oxy-acetylene mini torch to try to weld it w aluminum rods and see if it stuck today, but my buddy decided to be a no showI will post pics a little later
Reply:Originally Posted by dave powelsonThat pan is cast AL or Mg, I'll bet AL.You're beating a dead horse trying to effect any degree of a reliable repair that doesn't leak, etc.Time to buy a new pan and chalk this up to experience--using steel flux coreto weld AL really doesn't hack it.If this was effective--don't you think that others would be doing so?
Reply:Thank you for your replys. If its aluminum how come the welds stuck? Im sure they fused with the pan, theyre not coming off unless they get grinded off (which i did on one side). I realize steel flux welding aluminum isnt effective...if i had determined the pan was made of aluminum i wouldnt have tried to weld it Im beginning to think its stainless steel, is there a special way to weld stainless? Is it prone to cracking? Also someone mentioned weld contamination could be the problem, why would this cause the base material to crack?
Reply:Originally Posted by ride5150Thank you for your replys. If its aluminum how come the welds stuck? Im sure they fused with the pan, theyre not coming off unless they get grinded off (which i did on one side). I realize steel flux welding aluminum isnt effective...if i had determined the pan was made of aluminum i wouldnt have tried to weld it Im beginning to think its stainless steel, is there a special way to weld stainless? Is it prone to cracking? Also someone mentioned weld contamination could be the problem, why would this cause the base material to crack?