Correct weld toes / tie in

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I have been practicing more, and one thing that keeps coming up is having good tie in and toes.  I know what undercut looks like without a problem, but I am not really sure what good toes look like.  The only pictures that I have found on the internet don't really show the toes very well, so I figured that I would ask here.  The top weld profile shows, what I would consider, the nominal profile (That is no under cut or build up).  I think that proper tie in is more like the bottom picture however.  I have seen when I am welding what looks like the metal sucking up on to the vertical plate in a t joint and I think that is a sign of a good toe.  Am I mistaken, or do you have any recommendations for good pictures?
Reply:Hello ace86, here are a couple of photos of some weld cross-sections. The 1 photo shows a "serious" amount of overlap/cold lap, the other photo shows the profile of some padding: there are 3 examples, one with the correct amount of spacing between beads, one with the spacing too close causing the beads to end up looking more like a wave, and the third with the beads spaced just a bit too far apart leaving "valleys" between them. Hope this helps some with your question. Mainly, the toes of a bead should make a transition to the base metal that won't promote cracking/failure when torsional stresses and loads are applied to the weld joint. Best regards, Allanaevald
Reply:The re-entrant angle (where the toe of the bead meets the base metal, or subsequent weld metal), should be at 90 degrees or greater.Rich
Reply:I would respectfully disagree - 90 degree entry would create too much stress.Here are some pics of recommendations.(Just the first random pics I found)Last edited by MinnesotaDave; 06-10-2015 at 06:35 AM.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Sure, a nice shallow angle is better, but there has to be an allowable minimum angle. According to Navsea 1688, 90 degrees is the minimum allowed angle. It's on page 177/ Figure 1, here...( when pulling the speed bar down on the right column).http://ntpdb.ddlomni.com/TechPubs/16...B-010_1688.pdfThese are Navy specs.RichLast edited by steelsurgeon; 06-10-2015 at 01:18 PM.
Reply:To all thank you for the pictures.  They really do help.  Apparently I am searching for the wrong terms.  I am reading the NAVSEA stuff now.  However a question, If I may, steelsurgeon.  You say the minimum angle is 90*.  Do you mean the maximum angle instead?  I would think that if you went to say 95* that you would start to have something resembling Aevalds first picture with the cold lap.
Reply:Never mind.  I see that the number that you were referencing is measured differently from the pictures that Dave put up.
Reply:In Aevald's picture, the re-entrant angle on the left, is less than 90*. That is unacceptable. The re-entrant angle on the right, is greater than  90*. That is acceptable.In your first post pictures, the angle formed is ~95*, or so. That is acceptable.RichEDIT: The way the Navy measures angles, and the way that Dave's pictures measures them are opposite each other. Remember...a straight line is 180*.Last edited by steelsurgeon; 06-10-2015 at 01:45 PM.
Reply:Originally Posted by steelsurgeonSure, a nice shallow angle is better, but there has to be an allowable minimum angle. According to Navsea 1688, 90 degrees is the minimum allowed angle. It's on page 177/ Figure 1, here...( when pulling the speed bar down on the right column).http://ntpdb.ddlomni.com/TechPubs/16...B-010_1688.pdfThese are Navy specs.Rich
Reply:My pleasure, Dave...I have to work to these specs every day...Rich
Reply:Originally Posted by steelsurgeonMy pleasure, Dave...I have to work to these specs every day...Rich
Reply:That's a great outlook to have.  I have been doing critical welding since 1974, and I learn new things every day. I absolutely love that aspect of this trade.Rich