slag

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I've got a question about slag removal.  When I chip the slag off of my welds the hammer leaves small indentations in the bead.  This is especially true if I use the pointed end.  The indentations are only a couple of millimeters in depth and diameter but are they detrimental to the integrity of the weld or is this normal and nobody notices?Assuming I get all of the slag off of the top of the bead, there is frequently a small amount that is left in the margin of the bead, where the edges of the bead meet the base material.  I can remove this if I am persistent with a wire wheel and more chipping.  But again, the weld looks somewhat beaten from the chipping hammer  and if I get too intense with the wire wheel, the weld looks burnished or peened.  Again, is that changing of the appearance of the weld detrimental to its strength?  That first sight of the fresh bead when the slag comes off cleanly is something I'd like to keep.  Seems like de-slagging tens to ruin it.Any pointers?
Reply:Shouldn't be that much work getting the slag off.  Are you running stick or fluxcore?  I wouldn't worry about the dents.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:flux core slag is so sweet. i know exactly what you mean about the tiny pin holes indentions you get. my instructors have never said anything to me about it. we usually use a wire wheel though on 6010's and the 7018 slag usually comes off fairly easy.
Reply:The dents will actually help the weld by relieving some of the stress caused by shrinkage.                  MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:It will not affect the weld strength.  In some cases the dimples will show up on an X-ray as little shadows.  It has happened that a weld has been given a fail because the technician did not actually look at the surface and realize that the shadows were not subsurface defects.Wire brushing is no problem... in some cases the toes of fillet welds are actually run over with an angle grinder to blend the edges to the plate.  I am not telling you to grind the toes of your welds.  This is a procedure that is sometimes done on heavy plate ( half inch and larger)
Reply:If you want to avoid the dents for cosmetic reasons, drag the chiseledge end of the hammer along the weld and scrape. Often works better at getting out the slag than whacking. Power wire brush is the easiest, fastest, way, and most effective 95%of the time. The other 5%, it is chip, chip, chip.
Reply:I use 6011 predominantly.  I've noticed that 7013 slag does come off cleaner especially if I chip it right away.  I just wondered.  Thanks for the advice!My flux-core welds do not seem to have the same tenacious slag.  It comes off pretty completely.On another note, do you guys find that it is pretty common for some (I mean a very small amount, say at the toe of the weld) slag to be left on welds and then painted over?  In other words, does mild residual slag hinder the life of overlaying paint?
Reply:Anything underneath paint other than primer will affect the life of the paint.  Just depends on what you are doing and how clean you really want it.  When I paint, I pay particular attention to joints.  Slag under paint may fall off at any time, hence if paint is attached to the slag, then moisture can get underneath paint.Try 6013.  slag comes off easily and is a low amperage rod. 7018 is good but amp must be increased.  Don't know the thickness you are welding.
Reply:If all goes well..And it can..at times..One little tap and off it all goes..I love when that happens..Or it just curls up behind you as you go..Ahhh good times.. ...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Regarding the indentations from the chipping hammer, some rods call for the weld to be peened after quenching  and some without quenching. It relieves stress.
Reply:Oh....I'm not having particular problems removing the slag other than those instances mentioned above.  I'm just curious what effects leaving traces of it would have on the longevity of the weld or surface treatments like paint, etc.  Thank you for all of your responses!I also didnt know about peening or tapping to relieve stress.  I learn something new everyday!I'll have to post a couple of pics to show you guys some of my welds.  I'd like to get some critiques.Thanks again!
Reply:Originally Posted by zapsterOr it just curls up behind you as you go.....zap!