metal welding Multi-function hex wrench

Product Specifications

This custom multi-hex wrench is a critical on-board toolkit component designed for classic and commuter motorcycles (specifically compatible with S51/50, S70, KR51/2, SR50/80, and ETZ125/150/250 series). Featuring five integrated hex sizes (21/19/17/13/10mm), the tool incorporates a deep-drawn 21mm socket specifically engineered for recessed spark plug removal, combined with a rigid handle that accommodates the most common chassis and axle nut sizes.

Customer Requirement

Aftermarket motorcycle parts distributors frequently face end-user complaints regarding low-quality stamped toolkit wrenches. The standard failure modes include the internal hex cutouts rounding off under torque (which strips the vehicle’s fasteners) and the wrench body physically bending when operators attempt to break loose a seized spark plug. The client required a highly durable, cost-effective custom stamping wrench with strict dimensional tolerances on the hex cutouts and superior rust resistance for long-term storage in under-seat tool rolls.

Material Selection

We specified Q235B carbon steel for this multi-tool. For emergency on-board vehicle toolkits, Q235B provides an optimal balance of machinability and structural yield strength. The thickness of the steel plate delivers rigid leverage, entirely preventing the handle from flexing or snapping during heavy torque applications. Furthermore, Q235B responds exceptionally well to anti-corrosion surface treatments, extending the tool’s lifespan in harsh automotive environments.

Manufacturing Process & Tooling Development

Producing a multi-gauge wrench from heavy plate steel requires meticulous tonnage control to prevent material warping. We manufacture this component utilizing precision metal stamping. The primary engineering challenge is the 21mm spark plug socket, which requires a carefully calibrated deep-drawing process to extrude the steel collar to the correct depth without tearing or thinning the structural walls.

Following the drawing phase, precision piercing dies punch the 19/17/13/10mm hex openings along the handle. We strictly maintain sharp internal angles and zero-clearance tolerances on our piercing punches. This ensures the finished wrench aggressively grips the flats of the motorcycle nuts rather than the corners, completely eliminating the risk of rounding off stubborn fasteners.

Quality Control & Final Result

During the active stamping run, our QC technicians utilize hardened hex plug gauges to continuously verify the dimensional accuracy of all five openings against standard ISO fastener tolerances. Post-stamping, the entire wrench is mechanically deburred to remove sharp edges, ensuring operator comfort and safety. Finally, the tools undergo a high-adhesion zinc plating process. This creates a highly resilient, sacrificial barrier that guarantees the motorcycle toolkit hardware remains rust-free despite prolonged exposure to moisture, engine oil, and road grime.

Ready to optimize your custom hardware production? Contact our engineering team today for a technical consultation and OEM quote: xxn@lzkailai.com