CWB tips?

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I just did my BWB test today Flat ond horz and it opened up about 4mm on the face bend, the inspectior said that if i had of grinded it more it probly wouldn't have opened up if i had grinded it more, but when i was grinding it it was pretty flush, minus the desortion. Just wondering if anyone had any tips for this test that i could use for next time?
Reply:Guess some specs would be good. I was using 7018 1/8 with a Lincon Inverter (cant remember the model) with about 125 amps.
Reply:Is this an open butt plate bend test?6010 root with hot pass and 7018 out?If so, it will only open up if you have porosity or are not cleaning slag and smoke very well. 4mm is quite a bit. Treat every weld as if it were to be xrayed. Clean every stop and start, grind every stop and start.Good luck
Reply:No, that's a DOL where i'm from. The CWB is beveil on one side and just squar on the other with a backing plate.
Reply:Did you put a single wide weave cap on it?   The spacing at the root and backing bar is different for flat and horizontal positions.  The things that I notice is that people put wide caps on the test piece and get cold lap at the edges.   It is safer to cap it with two passes side by side or more.  There is no stipulation as to the number of passes.   Also something people miss is the first pass in the corner.  That fillet has a maximum size of 8mm if I remember correctly.  That is MAXIMUM.  There is no minimum so make sure you have good fusion in the corner rather than a big fillet weld.  If only your face failed then you have few worries.  The stop starts in the bottom are the difficult ones.    I am sure you can correct your cap with another chance at it...  You have to wait??  15 or 30 days??
Reply:30 days, it wasnt the face, it was the last root bend on both that cracked. But the inspector said if i had of grinded them down more they probly wouldn't have opened up. But how can you tell if there flush if they destort a bit? I mean from what i could see they were pretty flat, and i didnt want to grind to much
Reply:If it was the roots then make really sure your tie in at your stop start is good.. just practice stop starts until you can do them seamlessly.  Also take my size comment to heart and concentrate in making a small bead that burns right down to the corner.  Also make sure that you remove ALL reinforcement on the cap side.  If that cap sits above the base material when you bend it will put extra stress on the root since it will not bend evenly.
Reply:BUt like i said, it looked like it was grinded flush, but he said if i grinded it down more it wouldn't have opened, how can you tell if it's flush, i mean it it wasnt distorted you could use a squar or somthing, but with distoration how can you tell?
Reply:You can't really tell if you have ground enough ... it is just by eye.  It is very obvious if you have reduced the material below its normal thickness however.  You can't really put a straight edge on there but you can feel the change when you run your fingers across the surface.  When you flame cut your strips do not leave a cut strip under the burning area.  Hot spatter can put hard spots on your piece resulting in loss of ductility and failure.  I have heard from old hands that leaving pieces overnight will reduce chance of failure.  The idea being that hydrogen is still migrating hours afterward.... or the fairies are working their magic... Take your pick.  Certainly do not rush cooling.  I make sure all my surfaces , both root and cap are flush and all grind marks are running longtitudinally rather than across your strip.  The corners should be radiused 1/16 inch, matching an eighth inch electrode.Blodgett has a good outline:      http://weldingmag.com/blodgett/wdf_13719/Also note that if the corner opens up on a bend unless there is something obvious to indicate the cause of failure it is still a pass.  The guidelines varies but you are allowed 1/8 total opening ( 3mm)  On some codes you are allowed up to 1/8 inch opening total on EACH bend specimen. That is really making it too easy.It is very common for weld bend tests to fail from lack of preparation rather than lack of weld quality.
Reply:Well we cut them with the radio graph, so there not under the flame when they are cut, but as for the over night you really cant because it has to be donw in the 4 hours you have for the test.  WHat i did was restthem up against my fan so the fan would suck the hot air from them. Was that not a good idea or...?
Reply:The point I am making is that the spatter from a cut should not fall onto a test strip that is still laying in the bottom tray.  The strip should be removed from the tray immediately. I personally don't thing setting you pieces in an air stream will have any effect as long as they are not at a red heat any longer.  My feeling is that you have to pay attention to your root bead and your stop starts.  Certainly do a few practice tests on your own after shift to make sure you have it right.     C level welding students do this test over and over until they know it in their sleep.
Reply:Crispy_1, where do ya hail from?You can include this information in [U]    so that others can better help you.Gordie -- "I believe you understand what you think I said, but I'm not sure you realize that what you heard is not what I meant."
Reply:Nova scotia, and i've been doing them all year, most passed, but some failled. I'll just give it another shot in about a month