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123hotchef
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to cold
Not familiar with the purple stuff you've put on it. I'm assuming it's a t-fillet joint, mild steel.
Looks like a lack of fusion at the bottom for most of the joint so either insufficient power or you may have biased the upper portion of the plate. Also looks like a lot of porosity; was this MIG? If so, perhaps a gas problem.
Looks like a lack of fusion at the bottom for most of the joint so either insufficient power or you may have biased the upper portion of the plate. Also looks like a lot of porosity; was this MIG? If so, perhaps a gas problem.
123hotchef
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looks like that crack test spray
The_Yellow_Ardvark
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Hard to say with the dye on it and the angle.
Could be to cold.
I suspect a experienced welder or inspector will be along soon to help.
Or be able to advise on it.
It would help with some more images uploaded.
Oh.
Welcome to to forum.
slim_boy_fat
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Welcome aboard, BDan 
As others have said ^^, more information and perhaps pics from a better angle would help with answers.
As others have said ^^, more information and perhaps pics from a better angle would help with answers.
pedrobedro
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Porosity and lack of fusion, if it's a fillet I can't tell from the angle of the picture and it looks like it's laid in the angle and not really joined to either of the pieces of metal. I couldn't give the fault a specific name but it would have asterisks in it if I did 
On lack of fusion; try to keep your travel speed consistent and appropriate for the joint and material - I'd struggle to define a specific speed perse, but you'll know when you've got it. Also make sure you are manipulating the gun correctly and again consistently. Lack of fusion in the lower portion of a t-fillet joint can be caused by letting your hand holding the MIG gun droop so you gradually put more of the heat into the vertical portion of the joint. You can use your off hand, or better still an elbow with your off hand braced back onto your hand that's manipulating the gun to stead you. The gun angle will want to bisect the joint, so imagine a line aiming up from the center of where the two plates meet and aim the gun along that line, then lower the angle of the gun from strictly 90 degres vertical to closer to 80 degrees so the tip of the MIG gun is slightly pointing towards the direction you intend to travel.
For so much porosity I'd think there might be a supply problem, I've had similar happen if I ran a quick weld when I forgot to turn the gas on.
The_Yellow_Ardvark
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As they say.
Live and learn.
It is hard to say, why or what caused it from one image.
I would listen to those with more experience on it, than a WWW expert.
If you can, run it past a local welder, or was you who did the deed?
Can you get any more images?
It is not the lack of gas, that's for sure.
Oh yes, keep posting, keep you chin up.
The experienced members here will be happy to advise and help.
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It looks like a badly done DPI test
. The area should be cleaned, the dye sprayed on, cleaned, then sprayed white which then indicates any defects where the penetrant 'sticks' The photo does make it look like dye has just been sprayed on? Dunno, hard to tell.
The line of spots will be porosity or a contaminant which is being dragged along by the weld pool. The bottom 'thick' line could be a crack but its really rare on mild steel unless its a restrained joint. It might just be the dye clinging to the glassy 'slag' flakes on top of the weld which should be cleaned off before testing.
The test needs doing properly, then a decent photo for anyone to give any meaningful ideas. DPI isn't great on steel IMO, MPI is a better test. If it is porosity you shouldn't need a DPI test to tell you that - it should be pretty obvious to the naked eye. Nothing to suggest LOF.
. The area should be cleaned, the dye sprayed on, cleaned, then sprayed white which then indicates any defects where the penetrant 'sticks' The photo does make it look like dye has just been sprayed on? Dunno, hard to tell.The line of spots will be porosity or a contaminant which is being dragged along by the weld pool. The bottom 'thick' line could be a crack but its really rare on mild steel unless its a restrained joint. It might just be the dye clinging to the glassy 'slag' flakes on top of the weld which should be cleaned off before testing.
The test needs doing properly, then a decent photo for anyone to give any meaningful ideas. DPI isn't great on steel IMO, MPI is a better test. If it is porosity you shouldn't need a DPI test to tell you that - it should be pretty obvious to the naked eye. Nothing to suggest LOF.
Wedg1e
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If anyone needs MPI or DPI chemicals and isn't working under some QA regime then give me a shout, I may be able to rustle up recently-out-of-date stuff.
If I was going to be pedantic (
) then x-ray or ultrasonics would give you the best 'picture' of your weld but now you're into expensive equipment and three-year exam re-sits
If I was going to be pedantic (
) then x-ray or ultrasonics would give you the best 'picture' of your weld but now you're into expensive equipment and three-year exam re-sits 
Tinbasherdan
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To me it looks like a poorly performed dye pen test. Insufficient cleaning of the dye before the white coat was applied. Without a better picture there’s not a whole lot more can be said, other that any porosity issue is obviously down to gas shield quality.
Are all connections on the gas hoses tight? Is the shroud clear of spatter and crap? Finally, how close is the extractor to your workpiece. I get quite a few students that have th extractor near enough sat on workpiece sucking all the gas away
Are all connections on the gas hoses tight? Is the shroud clear of spatter and crap? Finally, how close is the extractor to your workpiece. I get quite a few students that have th extractor near enough sat on workpiece sucking all the gas away
The_Yellow_Ardvark
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@Tinbasherdan
There speaks of a man with experience.
Can I ask, what is the correct process of the dye test?
What can go wrong , if it is done wrong?
Thanks in advance Dan.
OH yes. TRITON!!!!!!!!!!!!!!!
There speaks of a man with experience.
Can I ask, what is the correct process of the dye test?
What can go wrong , if it is done wrong?
Thanks in advance Dan.
OH yes. TRITON!!!!!!!!!!!!!!!
Tinbasherdan
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As said by Paul, the dye should be sprayed on, allowed a few minutes then wiped off properly before the developer sprayed on. Not cleaning it properly will lead to the dye showing up everywhere and masking the true issue
The_Yellow_Ardvark
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@Tinbasherdan
Is that something done regularly, say on a welding course? Or is those type of welds done by eye?
I guess that for critical welds it is routine?
Is that something done regularly, say on a welding course? Or is those type of welds done by eye?
I guess that for critical welds it is routine?
