The KAH 412 LA is an automatic stud welding head built for CD and ARC stud welding with fully automatic stud feeding. It covers the full #4 to 5/16" weld range (M3 to M8), handles stud lengths from 0.31" to 1.57", and delivers consistent weld quality across mild steel, stainless, aluminum, and brass, including welding on painted sheet metal where surface conditions are less than ideal.
What separates the KAH 412 LA auto feed weld head from a standard manual stud welding gun is the combination of zero-play ball linear-bearing piston guidance, integrated lift damper, and automatic length compensation. Complete Stud Welding supplies the KAH 412 LA as part of a complete auto-feed stud welding equipment setup, including weld head, compatible welding units (CPW, MPW, ARC 800 AT), and all accessories configured to your stud size and material requirements from day one.
6 engineering decisions built into the KAH 412 LA that directly affect weld quality, production speed, and day-to-day usability as an auto-feed stud welding gun on a CNC system or standalone production line.
The welding piston runs in a zero-play ball linear bearing, not a plain bushing. That means the piston tracks the same path every single time. No lateral movement, no positional variation between shots.
Length tolerance variation across a batch of weld studs is a normal manufacturing reality. The KAH 412 LA handles it automatically through its integrated length adjustment. The gun compensates for stud-to-stud variation without operator intervention.
After the piston fires and the stud contacts the base metal, rebound in the piston creates a secondary contact event that degrades flash formation and weld strength. The KAH 412 LA uses a lift damper to control and minimize that rebound. The result is a more consistent 360-degree flash geometry and more predictable weld strength.
Most stud welding heads require bare metal contact to achieve reliable welds. The KAH 412 LA is specified for welding on painted sheets, provided the surface is clean, smooth, flat, and properly grounded. For automotive, appliance, or architectural sheet metal fabricators working with pre-painted stock, this expands where the auto feed stud welding equipment can be deployed without adding a surface prep step.
Switching between stud sizes on an automatic stud welding head normally means stopping the line to disassemble and reassemble the feed system. The KAH 412 LA uses a pushbutton detent system to release and swap the feed tube without tools.
Both lift and spring pressure have lock-in adjustment. Once the operator dials in the setting for a given stud size and base material, it locks. Vibration, cycle shock, and normal production wear cannot shift the setting between shots.
Not sure whether the KAH 412 LA is the right head for your application, stud range, or base material? Call us. We will walk through the process variants, stud size options, and compatible welding units to match the right configuration.
