KAH 412 LA - Automatic Stud Welding Head
The KAH 412 LA automatic stud welding head combines precise piston guidance with automatic length compensation for consistent stud welding on sheets from 0.5 mm. It handles M3–M8 studs and 8–40 mm lengths, while its zero-play linear bearing and lift damper help compensate for stud and workpiece variations during automated production.

Description / Features
Technology
- Automatic length compensation for stud and height variations
- Zero-play linear guidance for precise piston movement
- Lift damping to reduce piston rebound
- Integrated adjustment for lift and spring pressure
- Electronic control for consistent operation
- Automatic feeding directly into the chuck
Application
- Especially suitable for thin metal sheets from 0.5 mm.
- Automatic compensation of length tolerance of welding elements through integrated length adjustment
Structure
- Zero-play ball linear bearing for guiding the welding piston, to ensure maximum precision and reproducibility for welds
- Sealed welding piston guidance
- Integrated lift and spring-loaded adjustment
- Pushbutton detent system to facilitate changing the feeding tube
- Electronically controlled
Safety
- Lock-in spring adjustment
- Lock-in lift adjustment
- High level of security to prevent the selected settings being changed inadvertently
- Guidance system protected against spatters
Welding
- Individual adjustment options for optimum welding results
- Reproducible piston movement with minimized rebound effect for optimum welding quality via lift damper
- Automatic length compensation
- Welding on painted sheets possible (clean, smooth and flat surfaces and grounding required)
- Manual or fully automatic stud feed possible (welding element is automatically pushed through the feed tube in the chuck)
SPECIFICATIONS
| Welding range | M3 to M8, dia. 3 to 8 mm; #4 to 5/16", dia. #4 to 5/16" (dia. 10 to 12.7 mm; dia. 3/8" to 1/2" with modification only) |
| Stud length | 8 to 40 mm; 0.31" to 1.57" - (other lengths on request) |
| Stud type | Welding elements with flange according to current standards (other studs on request) |
| Stroke/Length compensation | 0.2"/0.08", 0.16"/0.12" |
| Spring pressure | Arresting |
| IP Code | IP 20 |
| Workplace noise level | > 90 dB (A) may occur during welding |
| Dimension LxWxH | 375 x 66 x 145 mm, 14.76" x 2.60" x 5.71" with chuck and quick change system |
| Weight | 3.4 kg; 7.50 lbs |
| Order No. | 94-37-412 (with length compensation) Equipped for one standard stud dimension according to customer request |
Where the KAH 412 LA Fits
| Application | Why It Fits |
|---|---|
| Thin Sheet Welding | Designed for sheets from 0.5 mm. |
| Variable Workpiece Heights | Automatic length compensation handles height variation. |
| Stud Length Variation | Compensates for welding-element length tolerances. |
| CNC Production Welding | Controlled piston movement suits automated systems. |
| Automated Production | Supports automatic stud feeding. |
| Sheet Metal Fabrication | M3–M8 range covers common flange studs. |
| OEM Production | Repeatable compensation supports recurring production. |
KAH 412 vs. KAH 412 LA
| Feature | KAH 412 | KAH 412 LA |
|---|---|---|
| Stud Range | M3–M8 | M3–M8 |
| Stud Length | 8–40 mm | 8–40 mm |
| Digital Piston Display | Yes | No |
| Automatic Length Compensation | No | Yes |
| Lift Damper | No | Yes |
| Automatic Feeding | Yes | Yes |
When to Choose KAH 412 LA
- Variable stud lengths
- Uneven workpiece heights
- Thin sheets from 0.5 mm
- Automated stud welding
- CNC production welding
- Applications requiring repeatable piston movement
FAQs
The KAH 412 LA is an automatic stud welding head with integrated length compensation. It is designed to maintain controlled stud positioning when welding element length or workpiece height varies.
Automatic length compensation adjusts for stud length tolerances and workpiece height variations, helping maintain consistent welding geometry without requiring manual correction for every component.
The key difference is the integrated automatic length compensation in the KAH 412 LA. It is designed for applications where stud length or workpiece height variation can affect consistent welding positioning.
The standard range is M3–M8 / #4–5/16", with 10–12.7 mm / 3/8–1/2" studs possible with modification. Standard stud lengths range from 8–40 mm.
Yes. The KAH 412 LA is especially suitable for sheets from 0.5 mm and provides controlled piston movement and length compensation for thin-sheet stud welding applications.
Yes. Its automatic feeding capability and controlled piston movement make the KAH 412 LA suitable for integration into CNC and automated stud welding systems.
The integrated lift damper minimizes piston rebound, helping produce more controlled and reproducible piston movement during the welding cycle and supporting consistent weld quality.
Yes, provided the surface is clean, smooth, and flat, and proper electrical grounding is established. Suitability ultimately depends on the coating and welding application.
APPLICABLE STUD WELDERS
IT 1002 AT
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All-rounder for automation.
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IT 90 AT
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4 outputs (optional), process monitoring and shielding gas.
For critical surfaces (e.g. galvanised).
For critical surfaces (e.g. galvanised).
CPW-Series
M3 to M8 (Dia. 10/12/12,7 mm only possible with modification)
Entry-level CNC stud welding machine with 1 welding head.
High speed with highest positioning accuracy by robust machine base frame.
Working with different work piece heights on a working range of 600 x 420 x 120 mm.
High speed with highest positioning accuracy by robust machine base frame.
Working with different work piece heights on a working range of 600 x 420 x 120 mm.
MPW-Series
M3 to M8 (Dia. 10/12/12.7 mm only possible with modification)
High performance CNC stud welding machine (with up to 4 welding heads).
Highest speed possible with high positioning accuracy through rugged design.
Very short set-up time (a.e. automatic calibration of Z-axes).
Network connection.
Highest speed possible with high positioning accuracy through rugged design.
Very short set-up time (a.e. automatic calibration of Z-axes).
Network connection.





