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I am a first year, I am currently laid off but want to show the shop that I work at that I am serious about this career choice so I am taking my CWB testing for MIG flat next week.A few weeks ago I took the test and failed for lack of fusion. I have been taking practice tests daily 3-5 of them. I am feeling way more confident now then last time I went in.I practice at a pre-apprentice program where they are busy and I do not get much feed back. Basically I am teaching myself to weld at the moment.I threw together some pics today of each step in the test, Hopefully some of you more experienced welders can throw a tip or two my way.
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Reply:my settings are 24.5V @300IMP on the roots. 23.5V @ 300 IPM on the cap. I fill it with 6 stringers. 3 tight little guys to get me to capping height, (second pic from bottom, on the left.)Last one with my hand is to show the cap height, Its under 1/8"NOTE: I am using a thicker backer bar than 1/4 as Its all I had from material today.
Reply:That is way more gap than Ive ever seen on a test plate!You need to slow down the wire speed, or speed up the travel speed. Attached ImagesDont pay any attention to meIm just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:hmm, My gap size is 1/2" I just use a piece of flat bar to gap it. I do not get much feedback other than "this is ****" from the only instructor there. Like, I have been given no insight into, how many beads to place in the root, capping etc.I Keep reading and seeing to just keep a small really tight HOT fillet weld in. Now, where My confusion comes in, I have been putting in my fillet according to the drawing, I am putting in a 5/16 fillet on the 90 angle and then my groove is more or less just a weave between that fillet weld the bevel side of the plate. I pause for a second on the fillet and the bevel to burn into each. Should I be using 3 passes in the root er...... I am really reaching lol, I know these welds are not great, but I can go in an practice welding without cost on my own time but I really want to practice correctly. _CWB_Procedure_and_Rules.pdfI am looking for a simple image of the test drawing, I uploaded a pdf of the CWB
Reply:I notice the bead stacking in the CWB illustration, it would be so much more helpful with some insight into the process.Last edited by TrueNorth; 04-14-2016 at 03:56 PM.
Reply:I generally put the root pass right down the center, and tie in all three plates. Then two passes on top of the root pass, then fill accordingly. I try to keep my welds small, just a little side to side motion. Only time I will weave is on vertical uphill welding. Attached ImagesDont pay any attention to meIm just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Thats the Double bevel with a 1/4 gap in the root right? the one I am taking is 1/2 " gap with a fillet weld on one side and a groove weld the other side which is a 30 degree bevel. 2 stop/restarts on each weldits a 1FG fillet/groove combohttp://www.gov.mb.ca/wdis/apprentice...ral_level1.pdfthere is a link to the drawing, page 5Last edited by TrueNorth; 04-14-2016 at 04:15 PM.
Reply:Originally Posted by TrueNorthThats the Double bevel with a 1/4 gap in the root right?
Reply:These are my observations. Yes you should definitely be using 3 passes on the root. I can see that the fillet side is way to cold, and you did not direct your arc right into the nook or root of the fillet. Your second pass was right in the middle of the gap. You have to direct the arc right at the sharp edge of the bevel side at the root to melt it back and burn it into the backing bar. That would leave the backer unwelded between the two. You can then reduce your amps if you wish and fill it in on the third root pass as it will be hot as blazes. Then fill and cap at your pleasure I guess. Just get it done before the timer goes off. That is the way I would approach it. You are not allowed cut, grind, of file any metal out according to your procedure guidelines, but I would take your chipper and beat the hell out of the restart area and scrap it out. Sometimes glass beads can leave slag -like inclusions behind. Oh, and start a bit ahead of your restart area and back into with the heated arc and then continue burning over your tracks. Cold starts are the devil.Last edited by shovelon; 04-14-2016 at 04:20 PM.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:CEP,Canadian welding bureau has some peculiar ideas about weld tests. Some of the CWB groove weld test plates I've seen have 20° included angle; that's 10° bevel angle on each side. (Not because I think you all out there can do the math, but so you know the first angle wasn't a typo) So what the OP is showing is not your typical AWS test plate with 1/2" root opening and 45° included angle.To the OP, your fill beads look really ropey and not well tied into the base metal on the bevels. Look at the bead photos that CEP posted for an example of what they should look like.What type and diameter of filler metal are you using? Solid wire or metal core? 0.8mm, 1.0mm, or 1.2mm? What shielding gas? Your voltage settings look low for any kind of spray transfer. Your wire feed speed settings might be too high for short circuit transfer. Which are you supposed to be using for the test?Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:On second thought I think I would do the fillet edge up to the restart area, stop and to to the groove side and weld to that restart area. Beat the hell out of the terminations and finish the fillet side, then go to the bevel side and finish that off. That way heat from the groove side will allow better fusion on the fillet restart. The groove start is a no-brainer anyway. Nothing according to the guidelines says you can't from what I read. Am I half-baked? Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by shovelon Oh, and start a bit ahead of your restart area and back into with the heated arc and then continue burning over your tracks. Cold starts are the devil.
Reply:Okay, I have some answers: I am using .035 wire with 75/25, no spray transfer. When I went the first time the inspector had me put in the fillet first (left to right), Inspect, Restart and finish the fillet. Inspect, Then the groove (right to left) stop and start with inspections each time too. Then you can cap at will in any direction.I am not sure how I would put in 3 and how the inspection process would be along the way If I asked them to do it that way.This is more or less my first certification to keep my foot in the door at the shop I was working at. Its not a chance be a big shot. I just seem to be yielding ****ty results on my own, tests are not cheap to fail every few weeks either
Reply:Originally Posted by A_DAB_will_doShovelon, I agree with your advice. But, like I said above, CWB has some peculiar notions about welder tests. The OP can't follow your advice in this test....page 4 section G - "NOTE: All restarts will initiate on the tapered crater (termination of weld) and continue outward."
Reply:I like 3 beads on the root pass as well. Ask the inspector/instructor if this is OK. What's the worst they can do to you for asking? For 3 beads, turn your settings down to 19V and 280 IPM of wire feed speed. This should reduce the amount of metal piling up on the plate. No weaving the bead, just a steady straight travel with a slight push angle. For the fillet side follow the root of the joint. Same for the bevel side. If allowed, then I'd deposit the third bead down the center to complete the root pass.The arc should crackle like frying bacon. The large spatter droplets on the test plate tell me your settings aren't quite right. They're almost what you'd use for spray transfer with a high argon gas mix.Pay close attention to the square side of the joint and make certain you focus the arc into the base metal and stay on the leading edge of the puddle. Wide weaving techniques may cause you lack of fusion problems with these lower settings, so just run stringers.3 beads for the root, 3 fill and 4 for the cap. If you can't make 3 beads work in the root then use 2 beads, but keep your weave as narrow as possible. You can experiement with using a slight drag angle if you prefer. Most seem to like pushing a short arc puddle, but I was taught to use a drag angle with it and you can pass bend tests while dragging the puddle no problem. Just keep the angle small, no more than 10 degrees either way.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Originally Posted by shovelonI dunno. The test guidelines posted by the Op state this Pg. 2 "Always restart the arc ahead of the crater where you stopped. Then move back into the crater, fill it and continue to weld."
Reply:Originally Posted by A_DAB_will_doAh, you looked at the docoment he linked to in post #6, and I looked at the document he linked to in post #9. And they give conflicting instructions. Lovely. Ask the inspector which to do. But I agree that starting ahead and circling quickly back into the crater will help avoid LOF problems at your restarts.
Reply:Originally Posted by TrueNorthI am using .035 wire with 75/25
Reply:So where was your lack of fusion in the previous test failure, root, mid or cap?ChrisAuction Addict
Reply:Originally Posted by milomiloSo where was your lack of fusion in the previous test failure, root, mid or cap?
Reply:Originally Posted by A_DAB_will_doI like 3 beads on the root pass as well. Ask the inspector/instructor if this is OK. What's the worst they can do to you for asking? For 3 beads, turn your settings down to 19V and 280 IPM of wire feed speed. This should reduce the amount of metal piling up on the plate. No weaving the bead, just a steady straight travel with a slight push angle. For the fillet side follow the root of the joint. Same for the bevel side. If allowed, then I'd deposit the third bead down the center to complete the root pass.The arc should crackle like frying bacon. The large spatter droplets on the test plate tell me your settings aren't quite right. They're almost what you'd use for spray transfer with a high argon gas mix.Pay close attention to the square side of the joint and make certain you focus the arc into the base metal and stay on the leading edge of the puddle. Wide weaving techniques may cause you lack of fusion problems with these lower settings, so just run stringers.3 beads for the root, 3 fill and 4 for the cap. If you can't make 3 beads work in the root then use 2 beads, but keep your weave as narrow as possible. You can experiement with using a slight drag angle if you prefer. Most seem to like pushing a short arc puddle, but I was taught to use a drag angle with it and you can pass bend tests while dragging the puddle no problem. Just keep the angle small, no more than 10 degrees either way.
Reply:Agreed with the above comments - and yes CWB is a little strange for most of the req'sIs there a guy at the shop that you work(ed) at that could show you the ropes?I have not done a GMAW CWB test, but the plates (and gaps) are the same for SMAW, and I have always done 2 passes for the root. Our CWB Inspector wanted both root passes in the same direction though.....I have mentioned this in the past in other posts, but you really have to talk to the inspector and see what they want for the particular test you are doing. It seems there is a bit of latitude on what is a "CWB Plate Test" depending on the inspector, location, etc.I would prep the plates down to shiny clean steel if possible before tacking them up - helps a but on mig to not have the mill scale.
Reply:Originally Posted by A_DAB_will_doAh, you looked at the docoment he linked to in post #6, and I looked at the document he linked to in post #9. And they give conflicting instructions. Lovely. Ask the inspector which to do. But I agree that starting ahead and circling quickly back into the crater will help avoid LOF problems at your restarts.As far as anyone to show me the ropes, not really. I have cart blanche on materials and a place to practice. As far as the instructor goes, I literally NEVER have had a demo, EVER. I went there as a student for 6 months. 3 of theory and shop, 3 of on site work at a local custom fab shop. The shop hired me but myself and anyone else other than 2 journeyman and a 3rd year were laid off. So i work a dead end job right now to pay the bills and practice welding as much as I can when ever I can.The instructor has current students to deal with and just lets me do my thing, I ask questions as much as I can but I am trying to be humble and not be his focus while I am there, that way the other people get the best out of the pre-apprenticeship program too. I have been doing these practice plates as seen above, under the impression that I needed to put a 5/16 fillet weld in, then a groove weld would then be weaved between the fillet and bevel edge consuming both to fuse all together, Now I am just confused
Reply:Originally Posted by TrueNorthAs far as anyone to show me the ropes, not really. I have cart blanche on materials and a place to practice. As far as the instructor goes, I literally NEVER have had a demo, EVER. I went there as a student for 6 months. 3 of theory and shop, 3 of on site work at a local custom fab shop. The shop hired me but myself and anyone else other than 2 journeyman and a 3rd year were laid off. So i work a dead end job right now to pay the bills and practice welding as much as I can when ever I can.The instructor has current students to deal with and just lets me do my thing, I ask questions as much as I can but I am trying to be humble and not be his focus while I am there, that way the other people get the best out of the pre-apprenticeship program too. I have been doing these practice plates as seen above, under the impression that I needed to put a 5/16 fillet weld in, then a groove weld would then be weaved between the fillet and bevel edge consuming both to fuse all together, Now I am just confused
Reply:This test procedure mentioned is strange. It might be particular to Alberta. I have done the CWB fillet groove test many times. It is pretty straightforward. Yes on the flat the gap is half inch which by coincidence is the width of a soapstone.... Handy thing to know. You are doing two tests in one. You are being tested to see if you can do a horizontal fillet weld with a stop start and a flat groove weld with a stop start. Almost all failures are at the stop starts. Normally this flat-horizontal test is done in spray ( high voltage like 28 and shielding gas with more than 80 % argon). You are to run the fillet weld first two thirds down the length of the plate to the inspector's mark the run a groove weld between the fillet and the bevelled edge of the plate going one third down the plate. You hand it to the inspector and he looks to see it is done properly. He uses a CWB stamp to mark your stop locations. He will then tell you to restart the fillet and run to the end then restart the groove and run to the end. The inspector must inspect your two stop starts again. If they pass the visual then you can proceed to fill it in making sure you don't have excessive build up on the cap.... Over three mm ( 1/8th ) is a fail. There are no rules about how you fill the groove. Some people like a big wide cap but unless you are experienced you risk cold lap at the edges of the cap. I would suggest two passes side by side since that gets rid of the risk of cold lap at the edges. When filling your plate will heat up. I find that turning the plate around so that you are starting at the opposite end for a few passes evens things out so that one end does not overheat. There is a rule that says your first fillet must be under 10mm in size. This is a distracter and confuses people. The 10 mm is MAXIMUM so make it smaller and concentrate in burning in the corner as you go. Some people will try to make a 10 mm fillet and get lack of fusion in the corner. I find that I start the arc ahead of the cold crater, whip back to fill the crater and continue on. I would discourage starting right on the crater. Three bends are done. The backing strip is peeled off and a root bend is done at both stop starts. A cap bend is done with the middle third of you plate. The actual plate can be cut and bend tested, inspected by Xray or inspected by ultrasound. Bend or Xray is most common. Any opening of a bend coupon more than 1/8th is a fail. If you have multiple little stars opening if they add up to more than 1/8th it is fail Usually this test is done with high heats in spray.... Not normally done at low voltages unless you are doing vertical, horizontal or overhead GMAW tests.Last edited by lotechman; 04-15-2016 at 06:21 PM.
Reply:Thank you for your in depth reply. I have been able to make it through the test phase to have my plate bent, The maximum fillet size was a confusing factor, I was under the impression that I was trying to get that size of a weld, equal legs and then tie my fillet into the groove. I will be taking the test under the same parameters that the shop i work at uses. solid .035 wire with 75/25 gas. Monday and tuesday I will be be devoting to practice. Wednesday is the test. I will Post a Part 2 to this thread on monday evening.
Reply:I've taken that same test in the horizontal position with .052 metal core wire. Boy howdy, talk about having to maintain some high travel speeds.
Reply:Originally Posted by TrueNorth I have been doing these practice plates as seen above, under the impression that I needed to put a 5/16 fillet weld in, then a groove weld would then be weaved between the fillet and bevel edge consuming both to fuse all together, Now I am just confused
Reply:Thank you for replying to my confusion. I am planning on putting all of this information you fella's have thrown at me to good use on monday. I will post a part 2 and update monday night. Your in depth input helps me out big time |
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发表于 2021-8-31 22:09:14