2G Root pass help

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I am trying to figure out how to do the root pass on a 2G plate test with backing bar, 7018, 1/4" gap, double bevel. I am using 1/8" 7018 at 130 amps, around 20 - 25 degree bevel. I usually do a 2 pass root Where I run my first bead on the bottom bevel and backing strap tying into both while leaving a gap on the top bevel and backing strap to penetrate the backing strap and top bevel. The problem is I can get a perfect first pass but the bevel angle doesn't allow me to get in that gap I leave to run my second pass. When I do it I get a bunch of trapped slag and incomplete fusion, the rod sputters because it has to long of a arc length. Is there a better way to run this root pass in 1 pass that will let me tie into the bottom bevel, backing strap, and top bevel? Once I get pass the root I am golden all the way to the cap, I just want a bullet proof way to run the root. The 2 pass method seems to work real good on 3G and 4G as I have passed both of these on inch thick.Right now I am practicing on 3/8" plate till I get the root solid, the west test I am prepping for will be 1" thick.Miller Maxstar 200 SDPiperliner #10 Gold
Reply:Picts would help. I have seen some guys lay down a lot of material when they weld. Others using the same rod and settings lay down quite a bit less material on their runs. That changes how each person runs a plate. One guy might be able to do a 1, 2, 3 bead joint, while another might need to do  a 2, 3, 4 ( or more) bead joint to fill the same v groove.You may be one of those guys who tends to lay a heavy bead. ( I am). You might need to either adjust your travel speed to lay down less material on your 1st pass, so as to leave more room for #2. Or you may need to aim down on the lower bevel a bit more to accomplish the same thing. I'd avoid going down much farther unless that's your only option. Problem with that is that I often see guys who can't correct so the cap ends up heavy at the bottom since that fills faster than the top does at that point. Last thing that I see on rare occasions is that people get in their own way. I don't see it much at all with 2G, but I have with some other positions.  Your plate position may be forcing you to weld in a way that doesn't make this work well for you. You might try dropping the plate some and see if that helps. It may be that your rod angle is pointing up  more on pass one, forcing material higher. While it's an "odd" way to do it, since you can weld overhead, you might reverse the order and try doing bead #2 at the top 1st. See if that leaves you with enough room at the bottom for that other bead. This may work if the plate is too high, but you can't move it lower ( or stand higher).Seeing what is happening would help..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Try using a weave pattern similar to writing a series of "U"s cursively to get the root laid in, in one pass.   Hold at the top of each leg of the "U" before sweeping down thru the bottom and back up again.    UUUUUUUUUUUUUU       Keep the rod angle pointed up toward the upper bevel.Last edited by HT2-4956; 07-04-2014 at 09:36 AM.
Reply:Originally Posted by DSWPicts would help. I have seen some guys lay down a lot of material when they weld. Others using the same rod and settings lay down quite a bit less material on their runs. That changes how each person runs a plate. One guy might be able to do a 1, 2, 3 bead joint, while another might need to do  a 2, 3, 4 ( or more) bead joint to fill the same v groove.You may be one of those guys who tends to lay a heavy bead. ( I am). You might need to either adjust your travel speed to lay down less material on your 1st pass, so as to leave more room for #2. Or you may need to aim down on the lower bevel a bit more to accomplish the same thing. I'd avoid going down much farther unless that's your only option. Problem with that is that I often see guys who can't correct so the cap ends up heavy at the bottom since that fills faster than the top does at that point. Last thing that I see on rare occasions is that people get in their own way. I don't see it much at all with 2G, but I have with some other positions.  Your plate position may be forcing you to weld in a way that doesn't make this work well for you. You might try dropping the plate some and see if that helps. It may be that your rod angle is pointing up  more on pass one, forcing material higher. While it's an "odd" way to do it, since you can weld overhead, you might reverse the order and try doing bead #2 at the top 1st. See if that leaves you with enough room at the bottom for that other bead. This may work if the plate is too high, but you can't move it lower ( or stand higher).Seeing what is happening would help.
Reply:Originally Posted by HT2-4956Try using a weave pattern similar to writing a series of "U"s cursively to get the root laid in, in one pass.   Hold at the top of each leg of the "U" before sweeping down thru the bottom and back up again.    UUUUUUUUUUUUUU       Keep the rod angle pointed up some.
Reply:On a small test plate assembly (like in your picture) there's really not a whole lot of heat sink.  So by the time you get to the cap the assembly is getting pretty hot and can't pull the heat out of the puddle as fast to make it freeze up before it can sag.   I compensate for that by turning the amperage down some before running the cap passes.So if you've put the root and fill in using 130 amps try going down to 120 for the cap.Last edited by HT2-4956; 07-04-2014 at 10:13 AM.
Reply:Originally Posted by HT2-4956On a small test plate assembly (like in your picture) there's really not a whole lot of heat sink.  So by the time you get to the cap the assembly is getting pretty hot and can't pull the heat out of the puddle as fast to make it freeze up before it can sag.   I compensate for that by turning the amperage down some before running the cap passes.So if you've put the root and fill in using 130 amps try going down to 120 for the cap.
Reply:Don't have any pictures of stick on a 2G test plate but this is some Metal Core wire on one.   I turned the settings down several times on the way out to compensate for the plate heating up.   Those black stripes are from where it just smoked a 500 F. temp stick when I checked it.   I probably could have made it look a little better using 4 smaller (quicker run) beads for the cap instead of the 3 bigger ones I put down.   It bent good.
Reply:How do you stop the plate from fish mouthing at the end of the plate and heading onto the run off tab on the cap? Should I build up the run off tab before capping it? At what temperature do you stop before putting a nother pass down.Miller Maxstar 200 SDPiperliner #10 Gold
Reply:I finally got ithere is the 2 root passes in the order I put them in.First passhttps://dl.dropboxusercontent.com/u/...704_135015.jpgSecond Passhttps://dl.dropboxusercontent.com/u/...704_135453.jpgThen I tried to get picks on the fill passes but they came out blurry. The pre cap pics came out okay.Flush before cappinghttps://dl.dropboxusercontent.com/u/...704_140319.jpgSide view pre cappinghttps://dl.dropboxusercontent.com/u/...704_141300.jpgCap!https://dl.dropboxusercontent.com/u/...704_142316.jpgSide View caphttps://dl.dropboxusercontent.com/u/...704_142331.jpgLet me know what you think and what I can do better. Root and fill were all done at 130 amps, with slight breaks in between + cleaning. Cap was done at 120.Miller Maxstar 200 SDPiperliner #10 Gold
Reply:Anyone?Miller Maxstar 200 SDPiperliner #10 Gold
Reply:Your consistency needs work.  I'd want to see a nice even bead at the toes without all the bumps and irregularities. I see that in pretty much all the ones I looked at..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by DSWYour consistency needs work.  I'd want to see a nice even bead at the toes without all the bumps and irregularities. I see that in pretty much all the ones I looked at.
Reply:Originally Posted by smilexelectricHow do you stop the plate from fish mouthing at the end of the plate and heading onto the run off tab on the cap? Should I build up the run off tab before capping it? At what temperature do you stop before putting a nother pass down.
Reply:Originally Posted by HT2-4956You can run some short vertical up fillet welds between the run off tab and the edge of the plates at the beginning and end to help get that area built up so you don't get that under filled condition where the groove transitions off on to the backing bar.   Don't wait until the very end before you cap to do it but rather build that area up in stages as the groove fills up.   Every time you put a pass (or layer) in the groove put one or two extra, short, vertical up beads at both ends on the backing bar.  This is a good place to use up any short partially burnt rods you've got laying about.  But if need be use a couple of new rods to accomplish this.   Taking the little bit of extra time to do this always reflects well on your workmanship.As to what temperature you stop at before putting another pass down (the "interpass temperature").....you need to adhere to what the procedure for the type of material your welding gives.   For just practicing on A36 test plates I'd think you wouldn't want it much over 500 F.    The hotter the plate is the more skill it's going to take you to get a nice even bead on there.   Past a certain point parameters like your amperage setting, travel speed, rod angle and manipulation get to be more and more critical.   It's hard to explain verbally.  You just have to keep practicing and trying different things and it will all soon start to become apparent to you.
Reply:Also..I agree with what DSW said about your consistency.   You've got to work at maintaining a lot more even travel speed as you weld.   About that split bead root.. that just doesn't seem like a very good idea to me.  With a 1/4" gap and a 1/8" 7018 I think you'd be way better off putting a one pass root in.   Even if it takes you more than one rod to do it.   As to propping...well, don't come to depend on having to be rigidly braced to make a smooth weld.  A little light bracing against your shoulder or hip isn't a bad thing but coming to depend on having you off hand elbow propped on something is in my opinion a bad idea.   You should practice and learn to weld one handed as much as possible.   And the way you do that is by staying relaxed.  Don't take a death grip on the stinger, consciously remind yourself (until it becomes habit) to keep your arms and shoulders relaxed.   Take as much of the weight of the lead going to your stinger off your hand as possible.  Hold it in your off hand or drape it over something to take most of the weight.   Don't fight you natural tendency to shake slightly because the more you do that the worse it will get.  You have to learn to make that little bit of wobble work for you.   Don't get discouraged, a little more practice and these little details will all start falling in to place for you and you'll be doing these plates just as slick as any of the rest of us.
Reply:Originally Posted by smilexelectricWhen I was running at 130 amps I had so much rod left by the end of the plate so I would run to the end of the backing bar, and trace back to the plate and backing bar transition and sat for a second or 2. Fixed the fishmouthing.
Reply:Originally Posted by HT2-4956Also..I agree with what DSW said about your consistency.   You've got to work at maintaining a lot more even travel speed as you weld.   About that split bead root.. that just doesn't seem like a very good idea to me.  With a 1/4" gap and a 1/8" 7018 I think you'd be way better off putting a one pass root in.   Even if it takes you more than one rod to do it.   As to propping...well, don't come to depend on having to be rigidly braced to make a smooth weld.  A little light bracing against your shoulder or hip isn't a bad thing but coming to depend on having you off hand elbow propped on something is in my opinion a bad idea.   You should practice and learn to weld one handed as much as possible.   And the way you do that is by staying relaxed.  Don't take a death grip on the stinger, consciously remind yourself (until it becomes habit) to keep your arms and shoulders relaxed.   Take as much of the weight of the lead going to your stinger off your hand as possible.  Hold it in your off hand or drape it over something to take most of the weight.   Don't fight you natural tendency to shake slightly because the more you do that the worse it will get.  You have to learn to make that little bit of wobble work for you.   Don't get discouraged, a little more practice and these little details will all start falling in to place for you and you'll be doing these plates just as slick as any of the rest of us.
Reply:Here is a 3G bend test that failed due to a linear inclusion in school. It had 1 spec on the bottom coupon about 3/4 the way up on the bevel side, and then a small linear inclusion on the top coupon. This was using the split root method, if I did not have that linear inclusion it would of passed. I got it the next shot, and then I passed the 4G Unlimited thickness first shot. I always did have a thing for overhead welding. These were side bends.Miller Maxstar 200 SDPiperliner #10 Gold