Metal cutting - oxyfuel cutting, plasma cutting, machining, grinding, and other preparatory work.
WelderDan
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I know that structural welds should be top notch, but what about welds done for aesthetic reasons? If you want a nice looking weld and most of it is good with a slag inclusion in part of it, would you grind out the whole weld and start over or just grind out the slag and weld over it? I imagine it depends on different things.

Are there any kinds of filler material that can be deposited into a slag hole that's been grinded out, other than welding metal into it, that will maintain a nice bead appearance?
Last edited by WelderDan on Sun Nov 17, 2019 3:37 am, edited 1 time in total.
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When grinding out a slag hole, try and get the metal back to close to base metal, maybe scratching some of the slag out. Then weld over it with higher amps. If you just try to weld over it, the shape of the hole will be too tight to burn the slag out
Poland308
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Common practice if you have a bad spot on a large structural weld or pipe weld would be to grind out only as much as you need to get rid of all inclusions, while making sure your creating a recognized joint shape. IE a v groove of acceptable width, depth, and angle.
I have more questions than answers

Josh
WelderDan
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Poland308 wrote:Common practice if you have a bad spot on a large structural weld or pipe weld would be to grind out only as much as you need to get rid of all inclusions, while making sure your creating a recognized joint shape. IE a v groove of acceptable width, depth, and angle.
Oh I get it.. So basically you create a new joint where the slag was and reweld that part. I'll keep that in mind. Maybe I won't be do nervous while welding, knowing this.
snoeproe
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Quality stick welds on structural that are top notch are sound, solid and also aesthetically pleasing.
A completed weld with a slag hole in it would not pass a visual inspection from a CWI and therefor needs to be repaired.
If this was a multi pass fillet weld, there's a good chance the buried slag started on the first pass and carried itself up through the rest of the weld passes.
When doing multi pass welds, when you run into problems in a particular pass, it needs to addressed immediately before it continues to follow you throughout the rest of the weld passes and a repair becomes more difficult and time consuming.
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