Lap weld guidance

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Looking for a bit of guidance. I now have my Syncro 250 up and running . I thought I'd start with Lap welds since they gave me a bit of trouble. I'm using 1/8 Excalibur 7018's on 1/4 plate. I've included a photo of my welds. I have two questions. I seem to have to push the rod against the plate in order to break off the shielding and keep a tight arc. If I don't it will long arc- Is that normal?I have a hard time not destroying the  corner of the top plate while filling in the weld- any suggestions? I get the feeling its just easier to Paint-in a new edge just behind the original.Opinions welcome, Gizzmo Attached Images
Reply:Originally Posted by gizzmoLooking for a bit of guidance. I now have my Syncro 250 up and running . I thought I'd start with Lap welds since they gave me a bit of trouble. I'm using 1/8 Excalibur 7018's on 1/4 plate. I've included a photo of my welds. I have two questions. I seem to have to push the rod against the plate in order to break off the shielding and keep a tight arc. If I don't it will long arc- Is that normal?I have a hard time not destroying the  corner of the top plate while filling in the weld- any suggestions? I get the feeling its just easier to Paint-in a new edge just behind the original.Opinions welcome, Gizzmo
Reply:Originally Posted by smilexelectricHave a hard time understanding this. Also give us your amperage range. and where is your ground clamp positioned? Are you talking about restarting a 7018 rod?
Reply:Originally Posted by gizzmoI'm having a hard time filling in all the way to the edge without distroying the edge. I'm running the rod at 125 amps  50% dig with the ground clamped to the work
Reply:Originally Posted by gizzmo I seem to have to push the rod against the plate in order to break off the shielding and keep a tight arc. If I don't it will long arc- Is that normal?I have a hard time not destroying the  corner of the top plate while filling in the weld- any suggestions?
Reply:Originally Posted by smilexelectricyou talkin the top edge? it looks like you only nipped it a few times. if thats what your talking about you just need to shove the rod into the corner and move a little faster so the puddle doesnt hit it. Also turn the dig off you don't really need it. On 1/4" you  need to to 2 passes over top off the root pass.
Reply:Originally Posted by smilexelectricOn 1/4" you  need to to 2 passes over top off the root pass. after your first pass aim the rod at the bottom toe of the first pass and let it overlap the first pass by 50% and then hit the top toe of your last bead, but becareful not to tear that edge up, let the puddle nip the edge.
Reply:Originally Posted by MinnesotaDaveBreak off the shielding?  I'm not sure what you are saying - but if it won't run without long-arcing your amps are too low.The top edge does not get destroyed - it becomes part of the weld. Check out this video on 1/8" lap joints and see if it clarifies what questions you want to ask.http://welding-tv.com/2012/10/10/sti...-old-buzz-box/Dave J.EDIT:  I see your amps are at 125 - that should be good.
Reply:Originally Posted by gizzmoThanks Smilelectric I was trying to do it in one pass. I'll give it a try and stack some up tomorrow. Just to make sure-- It's one root pass and two cover passes?Thanks , Gizzmo
Reply:Originally Posted by MinnesotaDaveBreak off the shielding?  I'm not sure what you are saying - but if it won't run without long-arcing your amps are too low.The top edge does not get destroyed - it becomes part of the weld. Check out this video on 1/8" lap joints and see if it clarifies what questions you want to ask.http://welding-tv.com/2012/10/10/sti...-old-buzz-box/Dave J.EDIT:  I see your amps are at 125 - that should be good.
Reply:If you look at the bead from the "end" it should look like a 45 deg angle roughly. 50% on the lower piece and 50% on the upper one. Where you melted the top edge, you were "aimed" too high and had more weld on the vertical edge and less on the lower piece. It's hard to tell from that angle, but it sort of looks like you might have 60% on the lower and 40% on the upper piece in many of those welds. Also from the pointy beads, it looks like you could slow down just a touch.Overall, not too bad..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:3 passes with 1/8th 7018 and 1/4" plate
Reply:Originally Posted by bullfrogg03 passes with 1/8th 7018 and 1/4" plate
Reply:Originally Posted by DSWIf you look at the bead from the "end" it should look like a 45 deg angle roughly. 50% on the lower piece and 50% on the upper one. Where you melted the top edge, you were "aimed" too high and had more weld on the vertical edge and less on the lower piece. It's hard to tell from that angle, but it sort of looks like you might have 60% on the lower and 40% on the upper piece in many of those welds. Also from the pointy beads, it looks like you could slow down just a touch.Overall, not too bad.
Reply:Originally Posted by bullfrogg03 passes with 1/8th 7018 and 1/4" plate
Reply:Originally Posted by smilexelectricPerfect timing bullfrog.
Reply:Originally Posted by bullfrogg03 passes with 1/8th 7018 and 1/4" plate
Reply:Originally Posted by bullfrogg0forgot to mention that was welded the Exxon way.  root, then top, then bottom
Reply:Well OF Course I didn't know that untill now LOL! I did it the root, bottom ,top way.First I tried once more to do it in a single pass ( I know but I'm stubborn)The rest is as suggested with three passes. I think it looks OK but what do I knowSuggestions welcome and thanks Attached Images
Reply:Looks good, just looks like you need to work on consistency. maybe a tad more heat.Miller Maxstar 200 SDPiperliner #10 Gold
Reply:need to clean the slag out more and stitch weld/tack the back side so the joint doesn't draw up on you.  the 3 pass deal you made looks pretty darn smooth.  mine would have neen better had I used new metal and new rods.  the rods I used had been in an open can inside a shed for the last 5 or 6 years.  lol
Reply:the way everyone gets taught to weld is root, bottom,  top.  fpr some reason Exxon decided that thwy like it better root top then bottom
Reply:Originally Posted by bullfrogg0need to clean the slag out more and stitch weld/tack the back side so the joint doesn't draw up on you.  the 3 pass deal you made looks pretty darn smooth.  mine would have neen better had I used new metal and new rods.  the rods I used had been in an open can inside a shed for the last 5 or 6 years.  lol
Reply:Originally Posted by smilexelectricLooks good, just looks like you need to work on consistency. maybe a tad more heat.
Reply:Originally Posted by gizzmoI have no such excuse. Even though I've only been welding for a week my rods and material are new.I'll try tacking the backside on the next go around. ThxGizzmo P.S. how do you like my wood table and old rotor welding table?Originally Posted by smilexelectricPretty darn good for a week. My welds didn't even look like that at 1 week.
Reply:Originally Posted by gizzmoI do have another  quick question... Can I/Should I rely on the rod to burn-out any slag I may have missed on a previous pass?
Reply:Originally Posted by DSWNo. While it can be done, it's a bad habit to get into. It's always best to clean all the contaminants off 1st to get good results. Often all you do is bury and hide the slag if you try and weld over it. When you get good, almost all the slag will come off with next to no effort. If the slag doesn't come off easily, that's usually an indication you don't have something just right yet. It might be rod angle, arc length or amps for example. Often it means you either have some undercutting or cold lap that is grabbing the slag and trapping it making it hard to remove.
Reply:still not bad for a yankee.
Reply:Originally Posted by gizzmoI did noticed the slag on the 1st pass was harder to remove. I'll try a few more amps and going slower on the 1st pass.Thanks, Gizzmo
Reply:Originally Posted by gizzmoI did noticed the slag on the 1st pass was harder to remove. I'll try a few more amps and going slower on the 1st pass.Thanks, Gizzmo
Reply:Originally Posted by DSWThat may help, but it all depends on WHY you are having issues. If the problem is cold lap, going slower may not be the issue if the problem is that you are laying down too much material . If you are having undercutting issues due to to long an arc, more amps will just aggravate the issue. ( I don't see either of these in your 1st post however)Increasing arc length also does much the same thing as upping the amps slightly. Take a look at the thread I did for Rick V. Note that I managed to get a nice smooth weld where the slag peeled off easily simply by increasing my arc length slightly even though my amps were fairly low. http://weldingweb.com/vbb/showthread.php?t=58537Understanding WHY you are having issues allows you to adapt to correct for the problem.The areas circled in green probably didn't give you much if any issues with slag removal especially at the bottom where things washed in well. However the red areas were probably difficult due to either undercutting or cold lap. Travel speed, rod angle and aim and possible arc length and amps might all have contributed to those red areas. I'd bet it was a combination of several of them to be honest. More picts from different angles would help to pin point issues.Try and keep the variables as constant as possible. Try to maintain the exact same rod angle, arc length and travel speed and vary only one thing if you make changes. I'd guess a large portion of your issues are based on inconsistency right now, mostly travel speed and aim point/rod angle. Even though I mentioned changing arc length above as an example, try and drag the rod right now while learning, to eliminate that variable. Try as hard as possible to maintain the same rod angle. Many students tend to "roll" their arm as the stick burns down. If you don't continue to adjust your wrist as you roll your arm, the rod angle becomes steeper as you go increasing arc length. Also many students loose sight of where they are aiming and tend to "wander" up and down with their aim point ( center and top red circles where you melted off the top edge look like a classic examples of getting "lost". Try and keep the rod in contact with both pieces at the same time to help eliminate this issue. Top red circle with the distinct "V" shape to the ripples also shows you were traveling way too fast.
Reply:Excellent replies gentlemen. I'll most definitely work on it.I did notice when I had smoother though smaller first passes the slag just curl up on it's own. Something to strive for. I found 'Not Knowing' what things should look like to be one of my biggest obstacles. Kind-of like reaching around in the dark for the thing that Doesn't Bite!I get some more time in today and post some progress shots. Thanks again for your time and responses. They help a great deal.GizzmoBullfrog0; still not bad for a yankee.
Reply:so why is it that you want to weld?  Hobby or potential job opportunities?
Reply:Originally Posted by gizzmoI have no such excuse. Even though I've only been welding for a week my rods and material are new.I'll try tacking the backside on the next go around. ThxGizzmo P.S. how do you like my wood table and old rotor welding table?
Reply:Originally Posted by bullfrogg0so why is it that you want to weld?  Hobby or potential job opportunities?
Reply:Originally Posted by farmersammAre you just being nice?Looks like the backside was already welded, or was it welded later?Either way, tacking/welding the opposite side wouldn't have done all that much anyway.  The force of the shrinking filler metal will pull the plate regardless.  Distortion is a given with any welding.The actual bend would occur on the 3 pass side even when tacked/welded on the back side.  The area directly under, or slightly outside, the fresh beads is the hinge point
Reply:OK a bit more practice and some observationsFirst - I was laying down my rod too much. As soon as I stood it up more the weld was smoother and the slag just fell off.Second - I was having a hard time seeing. I didn't catch that it was the sun flooding in the back of my helmet until today as it was Very Bright today.Lastly - I guest you might call it a rooky mistake- I was leaning over more and more as I fed the rod in. I was right on top of my weld by the time I was done. I realized it when the fumes began to get too much LOL! I concentrated on staying put and letting my arms do the work.The results:The first set of photo's is bottom-up and its the lowest weld in the set shown.The next set is me trying the top-down method and I have to say I really liked it! It was much easier to control the shape of the final weld and having more material at the top edge for the second pass made keeping it straight easier (for me anyway).Comments welcome and Thanks for the helpGizzmo Attached Images
Reply:The First picture of the top down set is my second pass.One more,Gizzmo Attached Images
Reply:looking better.  I must say that since I work out at Exxon I've grown to favor the top down method, but only if you tie in good to the top on the top pass and the bottom weld doesn't try to encompass the whole top pass
Reply:Been on some plate jobs where policy was only two passes with a wider first pass.  Interested in why Exxon goes with the top down three pass.  Any theories why it would be better?
Reply:Who is exxon or what is exxon. Looks better and better, your welds are flattening out. I would work on a more consistent travel speed still. Then flip her up and do it vertically and be ready for a much harder challenge.Personally I do bottom then top, I have tried both ways I still like bottom better.Miller Maxstar 200 SDPiperliner #10 Gold
Reply:I decided to move on to vertical Lap and see what I could do. There will be no pictures of how that day went! After recovering from laughing hysterically over my first attempts, I when about trying to at least being able to call them welds. I really struggled with the settings but I finally got it close enough to start to improve. One of the toughest tasks is to get the root pass in without too much undercut. I'm still working on it. It took hours for me to finally realize I was heating up my practice material and it was effecting my welds. After letting things cool down I tried again with the welds shown in these photos. I'm still struggling so feel free to make suggestions.I went with 2 passes as I was having trouble with sagging.1/8 7018 Excalibur at about 115 amps - arc control ( Dig) set at 75Gizzmo Attached Images
Reply:Take a close look at the two areas I circled. They show a classic case of not watching the puddle fill before moving on. Each time you jumped forward like that you ended up with undercut on the sides where the arc ate away at the base material, but the rod didn't stay there long enough to deposit material.This might have simply been due to erratic travel speed, but the result is the same. You moved before the rod filled in the bead. Drippy welds are usually the opposite. You spent too much time in that location, hence the extra material. Typically this happens when guys are trying to get the undercut to fill at the edges. They spend too long in the center often because they don't change their side to side speed based on what they see happening with the puddle. You have to remember that you cross the center twice, but are on the edges only once in each "cycle". You spend a count of say "1" on the left, swing across the center, then spend a count of "1" on the right, and then swing back across the center to where you "started" at and repeat. If when you cross the center you cross with a count of "1" then when you are done, you have spent a count of "2" in the center ( 1 going right, and 1 coming back left). It's not a constant timing pattern. .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:Thanks DWS I'll do more side-to-side and keep the timing in mind. Thanks for the reply. Is doing this joint in 2 passes the "recommended"  procedure?Thanks again, Gizzmo
Reply:Looks like a stick angle issue.. Keep it at 60 degrees into the fillet ... When you get to the edge, point it more to the base metal and let the puddle roll onto the corner from the base. Or direct arc into a hard pullHonestly, if you just keep burning rod and tweaking things, you will be gold... Look up a baseline heat in WPSSal
Reply:Depends. 1/4" is a bit much to fill in one pass with 1/8" rod, but it can be done. It's a lot easier if you go to a larger rod however. We usually use 3/8" plate and have the students do 3 passes, a root and then 2 to cover it. 1/4" with 2, you need to keep your 1st pass small so you don't over fill on the 2nd one or leave "gaps" when you try and stretch out the 2nd pass to lay down less material..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:I am curious. Not trying to jump in on anybodys post but do places make you run a stringer with lohi or wouldnt it be better to use some 7010 for the stringer then cap with one pass of lohi . Beings there is no real stringer (being a lap joint) just a fillet and cap. Just curious. I personally have welded in quite a few places but never had to run lohi as a first pass. I would personally turn the welder down looking at the elongated beads they should be round. Also if the slag is black it is too hot. Right?
Reply:Got some more hood time in today and things are getting better. I didn't bother with pics as they still look like crap but I have developed more control. It seems like the root pass responds well to a very short arc and an almost horizontal rod angle. On the second pass I was experimenting with a slightly longer arc and Bingo! I was able to see the puddle much better and exercise some more control over it. I was getting less gouging, undercut, things started to smooth out AND the slag just falls off ! I need to do more about tying in on the flat more but it's getting there. I bumped up the arc a bit too on the second pass and that helped smooth it out a bit. I tried the longer arc on the root pass but ended up with a huge keyhole every time. I'm at a point where I can work on pace and reading the puddle better to fill-in. I'll get some pictures up when the welds are showing more consistent improvement.Thanks for all the advice! Gizzmo
Reply:Ide recommend keeping a short arc in all applications, the larger the arc, the more heat it will produce and the more chance you have of getting porosity because the shielding vapor cloud from the flux is further from the weld puddle, keep it tight, dont necessarily have to scrub the puddle with pressure on the rod but a tight gap has always been recommended by every weldor ive ever had the pleasure to work with. Seeing the puddle and keeping the slag puddle behind the weld puddle will depend on your stick angle.But to each their ownSalSal