spot / plug welds fail

[sardine]

not having much luck with plug welds on sheet, 16 gauge hinges on 3 mm, the edge of the hole on the top hinge won't fuse into the puddle, iv'e gone in a little circle and created a huge puddle the size of a volcano, but still failing, anyone got any tips ?

 

[mike 109444]

In what way are they failing? If the hindges are premade (off the shelf) then they maybe zinc coated (bright silver in colour?) if so then you will need to grind that off.
Pics help.....

 

[gordon stephenson]

You have to make sure that you arc up on the parent metal, i.e.: in the centre of the hole.get a puddle going then circle round to catch the hinge metal,