OT - Welding Wire Size

[Grounded63]

The welds are flatter because of the higher/more aggressive settings. This gets the weld pool up to temp fast, where it will make a full penetration weld that flows out. Rather than producing a weld bead that sits on top of the base metal. With minimal penetration on the opposite side.

My welder has a spot/plug/stitch timer. With some recommended heat/wire feed settings for that. I don't usually use the timer, but use the heat/wire settings for it. Clipping your wire after each plug/spot weld can also help. To get more consistent welds if your doing multiple plug/spot welds.

Maybe check your manual to see if it has spot/plug setting recommendations in it. If it's not on the machine.