Welding "coupons" question

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Ive seen so many videos of folks welding the coupons and then bend testing.  Well I wanted to try it just for my own amusement!  Am I doing it "right?"  Tonight I tried 2 4" pieces of quarter mild steel welded with 2 passes of 6013 on each side.  Then it occurred to me that perhaps people who are actually taking the test can't weld both sides?  Because you can't weld both seams on a pipe...thats my theory.  So what is the correct procedure? Just for giggles, tomorrow I will put my current coupon in my dake with the 85 degree brake.
Reply:Picts have been posted on this here before. Ones above are for AWS D1.1 structural tests, typically  done with 7018. There are plenty of other tests, like for pipe say where it's open root with 6010 and fill and cap with 7018. That test would be a bit different..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 LarryLarryIve seen so many videos of folks welding the coupons and then bend testing.  Well I wanted to try it just for my own amusement!  Am I doing it "right?"  Tonight I tried 2 4" pieces of quarter mild steel welded with 2 passes of 6013 on each side.  Then it occurred to me that perhaps people who are actually taking the test can't weld both sides?  Because you can't weld both seams on a pipe...thats my theory.  So what is the correct procedure? Just for giggles, tomorrow I will put my current coupon in my dake with the 85 degree brake.
Reply:Thanks to both of you!  I have some 7018 Lincoln part number ED030568...it says E7018 3/32 on the outside but the rods say 7018AC.  I am inverter welding at DCEP.  Seems like this rod should work at DCEP as well according to the box but why would the rod say 7018AC then?
Reply:7018AC has extra additives to help stabilize the arc when the polarity switches back and forth from + to - in AC. In theory it allows guys with AC only machines to use 7018. In practice, not all AC machines will run 7018 AC well, even if it's supposed to be designed with them in mind.Personally I've never really liked the arc/ slag on 7018 AC, I prefer a rod like Excalibur that is really designed for DC+. To me the puddle on 7018AC is "muddy" and harder to read due to the slag..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:So I can use the AC rods but its not ideal.  I'll go back and see if I can find regular 7018.  Although the 7018AC do say I can use DC+.
Reply:A lot of this is personal preference. Some guys like one brand/"model" and hate something different. 7018Ac will run on DC+. I just don't care for the characteristics of that particular "flavor" of 7018. The tech school uses a couple of different "flavors" of 7018. I can usually tell right away if the rod I grabbed is Excalibur or not from the way it welds. Other ones are so so, and one or two types are just a pain to try and work with. Some of the ones I dislike, others love. Usually if I really hate the way that rod is welding, I can almost bet the box they just opened is 7018AC..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:If anybody is interested here is a pipe detail. Out of an AWS book. Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Thanks guys.  I assumed that if it said AC then it would only run AC...I'll give it a try on DC and I'll probably grab a 5 pound box of regular 7018 at lunch today anyway.
Reply:Would anyone be kind enough to let me know why I get that crack in my bead at the bend?This is 1/4" welded single pass at the bend area with 7018 at 220V 80amp.  Rods were lincoln.  I'd like to practice more but want to see what I could do to improve my skills to work toward a sound weld at the 90 degree bend. Attached Images
Reply:I don’t see a crack. But seeing all those dingle berries, I’d say you had way too much arc length.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:Yes arc length was too long - I need to get a tighter arc. Will practice that tonight. The crack is at the leading edge of the bend. It did not stretch with the bend. I used 3/32 last night but I think I'll give 1/8 7018 a shot next round.
Reply:A long arc length will make some what of a weak weld. That could be your problem with the crack.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:I am going to tighten it up.  Would you say that a good weld should always be able to handle being put in a metal brake at 90 degrees?
Reply:Yes I do. Even tho AWS bend tests they use a 1 1/2" diameter die. if you want to have some fun, do some fillet weld break tests. Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:send me a couple of your welded coupons and ill be glad to bend them for you for free. I'm in Vancouver  WA Attached Images
Reply:Nice! Right now I am just playing around and using my brake to get a hang of stick welding. If I get to the point of needing a more official test I think I am going to take you up on that offer!  Are you grinding the weld flat before bending?
Reply:Also a good way to see how your penetrating is weld up a 1/4 plate and cut it in half and etch it. 1/4 AL welded with my 230 amp machine. Weave on the left and stringer on the right. And this was welded uphill
Reply:Well tomorrow I will be bending tonights coupon into a 90. Now I ran 1/8 7018 at 119 amps 220V.  This was on the same 1/4" mild steel.  Still got tons of spatter tonight even with my tight arc.  While welding it looks like fireworks with all those boogers flying off.  I held the arc tight.  Any tighter and the stick would have been really buried.
Reply:I think you need to practice general welding a little more before trying to pass bend tests.
Reply:Originally Posted by Welder DaveI think you need to practice general welding a little more before trying to pass bend tests.
Reply:I don't think it's a prep problem. I think it's more of an inexperience problem. Maybe you're burning too hot or too cold? Lots of variables could cause all the spatter.
Reply:My thought is running too hot.  120 amp on 7018 for 1/4 was probably a bit high.  I think I need to be ok with holding the rod and not just the clamp.  When I am welding I need to remember to grab that stick to stabilize.
Reply:Lets see a pic of a welded t joint!
Reply:I can do that!  I will get one done up and put it on the bandsaw.  But I fear my penetration into the joint will be comedic...That's ok. You will need to turn up the amps more or go slower then. A test will tell.