Automated Welding w/ Metal Core

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Hey guys,I thought I'd make my first real post after lurking for a while... So I work for a small manufacturing company as a mechanical engineer, we do a large variety of ag equipment. I'm no pro-welder, but I know how to weld.. In school I did my emphasis in manufacturing/welding, so I was able to learn g-code for CNC's and also took a course on robotic welding and get some great hands on experience. We recently purchased a used PerformArc welding cell and I've kind of been the one in charge of getting it up and running since I'm the only one in the company that has any experience running them.That was quite the adventure, we had lots of weird little electrical issues to begin with but now that's all resolved and it's working great.. So we've also been playing with different wires. We've mostly been trying .045" Hobart 86R metalcore by recommendation from a friend of mine who works for Miller and also our supplier, but we have also tried .045" Lincoln Metalshield and some of the .045" solidwire the rest of our shop runs (on Deltawelds). Also I should say it has a Miller Auto-Axcess 450 power supply.. We've been running the Accu-Pulse program on 90/10 and have been pretty happy with the results so far. We are just running 33 lb spools until we decide what we want to stick with. Personally, I like the 86R over anything else, however I know it's the more expensive wire. The robot will be welding anything from 12 gauge up to 1" thick steel, most common probably being 3/16"-1/2".Does anyone have any experience with switching from solidwire to metalcore? It seems like I really have been able to get some faster travel speeds with the metalcore over the solidwire. I don't claim the welds to be perfect (we are still working on dialing in the parameters) but I believe they're decent quality. Also, if anyone has any advice with pulsing MCAW, I'd love to hear it. This is my first experience ever using metalcore wire. We're running about 400 WFS, 55 trim, with a travel speed of 11 in/min for 5/16" fillets and 320 WFS, 55 trim, and 12.6 in/min for 1/4" fillets. Both are with a weave since we will be using thru-arc seam tracking most of the time. I'm also curious if there's anyone with robotic welding experience on here? It's definitely keeping me busy at work, and has been a lot to take on. But so far management seems to be pretty happy with how things are going. I'll try to post some pictures when I can. Thanks!Pic 1: Hobart 86R with seam tracking. It may say 30V, but that is just what I program in as the voltage to the controller... It adds that to the arc control setting on the Auto-Axcess (currently 25, so it runs at 55).Pic 2: Parts had 6 1" stitch welds, 3 top and 3 bottom.Pic 3: Sorry this one got flipped for some reason. First tests with the seam tracking. The original weld that was taught had the joint perpendicular with the flat bar used as a locator. The gun is at the end point of the bead, showing how far the taught point is from the actual joint. The arc start point however is still in the joint at the top.Pic 4:This one also flipped.. The weld with the seam track. I adjusted the weave a bit after this, it didn't come down far enough on the toe, but you get the point with the seam tracking, it's pretty neat and is going to be useful!Last edited by andyh19; 04-23-2016 at 01:41 AM.Reason: Pics added
Reply:What kind of testing are you doing to test weld strength? What shielding gas, base material? For 1/4" and up I don't see why you don't run a larger wire like an .052 or 1/16". You should be able to get some fantastic deposition rates with automation. --Gol'
Reply:Originally Posted by Go1lumWhat kind of testing are you doing to test weld strength? What shielding gas, base material? For 1/4" and up I don't see why you don't run a larger wire like an .052 or 1/16". You should be able to get some fantastic deposition rates with automation.
Reply:andyh19,First off, welcome to the forums.Interesting project and it looks like your well on your way to getting things figured out and really improving your companies welding capabilities.   I've got quite a bit of experience welding with 86R manually but don't have any real robotic welding experience to speak of so I wouldn't have much help to offer as far as that side of it goes.  Here's some bend tests I did on 3/8" plate groove welds as part of getting a procedure qualified with 86R.   I don't see any reason you couldn't have the robot do the same thing and then test them.
Reply:This is some .045 86R on rolled pipe. I think it welds really nice.  Last edited by HT2-4956; 04-23-2016 at 11:33 AM.
Reply:Those bend tests look great! I'm going to do some asking around at work on Monday, I've been told years ago they had someone come in and certify the welders.. So I'm hoping that means they already have a jig. If not we will just make one. It would be great to know for sure that the seam tracking parameters I program in are giving us a sound weld. Sadly, to some guys in our shop, if the bead looks great they automatically assume it's a good weld. That 86R really does weld nice! Do you pulse with it? Or just spray?
Reply:Most robotic welding is done with hard wire mig to eliminate cleanup the best Lincoln L-56 cost more but free of problems.Metal core is expensive and not needed ,see Ed Craigs comments on weld reality.You will never get it qualified in NY city DOT!
Reply:Cleanup with metalcore? What cleanup? So far my experience with the metal core has been great, we still are going to do a bit more testing with it before we commit. But doesn't it give better penetration when compared to hardwire? And yes I've read his stuff before on pulse and what not.. We've seen other ag equipment manufacturers switch to it 100% (we are just using t for the robot for the higher deposition) and not have any issues. And why would I care what qualifies in NYC DOT? We're an Ag Equipment manufacturer in Idaho..Last edited by andyh19; 04-24-2016 at 02:07 PM.
Reply:andy,I started a thread on metal core a while back that you might find interesting.  There's a few other forum members that contributed some good information to it also.   http://weldingweb.com/vbb/showthread.php...ght=metal+core
Reply:Originally Posted by andyh19Those bend tests look great! I'm going to do some asking around at work on Monday, I've been told years ago they had someone come in and certify the welders.. So I'm hoping that means they already have a jig. If not we will just make one. It would be great to know for sure that the seam tracking parameters I program in are giving us a sound weld. Sadly, to some guys in our shop, if the bead looks great they automatically assume it's a good weld. That 86R really does weld nice! Do you pulse with it? Or just spray?
Reply:Thanks for the link to that thread! Lots of great stuff in there. Seems like somebody really has some very hard feelings against metal core after reading that thread as well...  So after running it a bit on the robot, our shop got some rolls of 86R to try out for themselves. Almost everything they weld is with ER70S-6, but there's one or two applications where they prefer metal core. They've used Lincoln Metalshield MC-6 in the past, it will be interesting to see how they like the 86R.
Reply:Originally Posted by andyh19Thanks for the link to that thread! Lots of great stuff in there. Seems like somebody really has some very hard feelings against metal core after reading that thread as well...  So after running it a bit on the robot, our shop got some rolls of 86R to try out for themselves. Almost everything they weld is with ER70S-6, but there's one or two applications where they prefer metal core. They've used Lincoln Metalshield MC-6 in the past, it will be interesting to see how they like the 86R.
Reply:We have a similar setup in our shop. We have a big argon tank and a big CO2 tank that get sent through a mixer (set to 90/10) and then we have lines plumbed to all the welding bays. It actually used to be setup as a tri-mix (90 Ar/8 CO2/ 2 O2) but that was years ago, before my time. And actually earlier this week, we did some welds on 3/8" and 1/2" plate and etched them. Here's the results from the 1/2" plate: