Constant slag inclusions/pin holes in welds.

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So this weekend I started my cart for my maxstar finally. But ever since I have been using this maxstar I keep getting little holes with slag in them on almost every bead. Its regular old cold rolled/hot rolled ground to shine. No grease straight from steel supplier. I used mostly 6013 on my cart at around 80-95 amps. The tubing was 1.5"x1/8" wall. Some beads came out free of any slag, but then some came out terrible. I also tried a Hobart 7018 around 95 amps and it did it as well, same thing with a lincoln 7018AC. If all the metal is clean, rod angle, arc length, and travel speed is fine what is causing this. I have welded on far worse steel than this crap and have never had this problem before. Could something like voltage, amperage drop be causing this?Miller Maxstar 200 SDPiperliner #10 Gold
Reply:If it is welding it should be getting the voltage/amperage required. I think I read that it can be +-10% 120V/240V I don't remember for sure. Are you using the machine on 120v or 240v? If you are on 120v then you are near the max amperage for stick welding. When I use my Maxstar on 120v it seems to weld a little colder than the listed amperage on the knob but I haven't had trouble with pinholes. Be sure to check the electrodes you are using for cracks/missing flux, I have had times when I didn't check and got porosity because of that. What size electrodes are you using? I assume 3/32" from the amperage but I have seen guys try to weld really cold and have trouble..Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Crap steel ? It happens. Not too often but likely more in the years to come.Think of steel as beer. The recipe has to be right. ESPECIALLY when it comes to tool steel.Last edited by Burpee; 11-03-2013 at 05:34 PM.Bubble gumTooth pixDuct tapeBlack glueGBMF hammerScrew gun --bad battery (see above)
Reply:Originally Posted by smilexelectric No grease straight from steel supplier.
Reply:Originally Posted by DSWI'm not sure if you are saying that it's new material, therefore it's "clean" or if you mean you have degreased it after you bought it. A lot of the steel I get from the supplier has a protective layer of oil on it. It's filthy unless I wipe it down and degrease it even though it's new material.
Reply:Arc blow? Just a random idea. Have pictures of the welds? Pictures of other welds made with the same electrodes/machine?Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Originally Posted by SquirmyPugArc blow? Just a random idea. Have pictures of the welds? Pictures of other welds made with the same electrodes/machine?
Reply:I'd heat the weld zones up with a torch.Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Originally Posted by SquirmyPugArc blow? Just a random idea. Have pictures of the welds? Pictures of other welds made with the same electrodes/machine?
Reply:Changing rod angle/ welding direction/ ground location..Lots of things can help with arc blow. One thing I have noticed with the Maxstar is it needs a good ground, when I don't have a good ground the rods stick really bad. Need to clamp to a clean spot, leaning a piece of steel onto the workpiece may not give a good ground and could be part of the problem. If you can't find another way just be sure the steel is ground clean where it is touching the grounded steel (also ground clean). Add some weight to the steel so that there is less chance of it moving and causing a bad ground.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Originally Posted by smilexelectricWhen dealing with arc blow how do you fix it
Reply:Oh man I completely fudged on cleaning the ground clamp area. Doh.Miller Maxstar 200 SDPiperliner #10 Gold
Reply:Arc blow on a tube frame weld cart? I can't see it. Where is your porosity developing? Is it in your entire bead? Just at the start of your bead? Or at the end of your bead?JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:I'm suspecting that too long of arc length and or improper rod angle may be your issue resulting in loss of shielding which will lead to porosity issues.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:Are your rods wet, moist?I have a maxstar 200 DX and weld carbon pipe all day. No real cleaning and just a brass ground clamp, where ever I can attach it (40' away on a pipe hanger, structural steel) nothing fancy.Local 83
Reply:Those slag inclusions are easy to get with 6013. What I have found works best:Pause after the arc is struck long enough to form a puddle connecting both pieces, then proceed. Maintain a short arc gap (smaller than rod diameter). Lightly dragging the coating is OK.7018s do not usually have that issue but again too long an arc gap may be the cause.Arc blow is usually worst in inside corners, such as boxes or frames made from angle iron. If you have to weld inside corners with DC, start right in the corner and move outward; avoid welding into the corner.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:Could always tack a piece of flat steel near to the welding area and clamp that.