Unique Cars - - WORKSHOP BASICS -


Volt­age al­ters the pro­file. The bot­tom bead was welded at rec­om­mended set­tings, the mid­dle 4V higher and the top 4V lower. The low-volt­age bead is stringy and has hardly pen­e­trated. The over-volt­age bead is wide with no ex­tra pen­e­tra­tion.

TORCH DIS­TANCE Hold­ing the torch too far away (top) will re­sult in a poorly-con­trolled weld with a lack of gas cov­er­age caus­ing poros­ity. Hold­ing it too close (mid­dle) will ob­scure the sight of the pud­dle, mak­ing it hard to con­trol. The bot­tom weld is cor­rect.

WIRE SPEED The top bead is too slow; the mid­dle is too fast; and the bot­tom is as rec­om­mended. It’s dif­fi­cult not to com­pen­sate by mov­ing the torch at a dif­fer­ent speed, so the re­sults are sub­tle. There’s a clear vari­a­tion in bead height, how­ever.

TRAVEL SPEED If you move too fast (top), the weld pool won’t have time to melt the base metal. If you move too slowly (mid­dle), the pool will melt in too much, be­com­ing wide and burn­ing through thin metal. The bot­tom bead was at the cor­rect speed.


Weld suc­ces­sive beads on a steel plate. Al­ter­nate be­tween push and pull, and left and right hands (this am­bidex­trous­ness will be handy for real-world work). Clean out the torch noz­zle reg­u­larly to pre­vent a build-up of spat­ter.







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