The teacher or a professional guest demonstrate the proper use of the Wire-feed Welder.
If students have passed the safety tests for
Gas and
Arc welding they may use the Wire-feed welder to make practice welds. Three welds, (Straight bead, Butt, and Lap) must be turned in for a grade.
Evaluation:
1 point for cleaning of welds prior to turning in
3 points for each weld based on the quality of the weld including:
Appearance
Penetration
Lack of defects such as porosity, craters, and undercutting
10 Points Total
Bead A: Too cold. It doesn't flow under the base metal around it. It's more like the bead is resting on top of the metal like a caterpillar. This is a weld that did not have proper heat.
Bead B: This bead good. It's rounded and you can notice that ripples in the weld bead. It also flows nicely into the metal.
Bead C: Too much heat. There is no definition at all. It's almost flush with the metal.