Shoulder Punches - Lapping Single-Stepped Shank

Shoulder punches with a single-stepped shank are used in precision toolrooms and production dies where stable guidance during lapping and heavy-duty punching is critical. The stepped shank helps maintain alignment while the punch tip is lapped to size, improving repeatability in forming and reducing variability between cavities.

• Automotive connector and terminal dies: Select hardened D2 (SKD11), M2 (SKH51), or SKH40 for durable punch tips that must resist wear while achieving controlled surface finish during lapping.
• Electronics and thin-gauge stamping: The shoulder geometry supports consistent positioning during material piercing, while the available tip shapes (round, rectangle, oblong, double-flatted round) help match different land and clearance requirements.
• General industrial punch tooling: For applications requiring controlled fit in punch holders, the specified shank diameter tolerance (+0.005/0, m5) supports predictable seating and reduced lateral movement.

This variant’s hardened steel options and lapping-focused shank guidance make it well suited for processes that combine alignment stability with wear resistance.

Choose between three hardened tool-steel families based on wear and toughness needs. SKD11 (D2 equivalent) is a high-carbon chromium tool steel typically used when abrasion resistance and dimensional stability are prioritized during punching.

• SKD11 (D2): Often selected for its strong wear performance; balance of hardness and toughness is achieved through quenching and tempering.
• SKH51 (M2 equivalent): A high-speed steel grade (AISI M2 equivalent) suited for higher cutting resistance and improved hot wear behavior; generally supplied in a heat-treated condition to reach the working hardness.
• SKH40 (powdered high-speed steel): Powder metallurgy processing refines carbide distribution, improving wear resistance while retaining toughness for demanding lapping and punching cycles.

Hardness and exact HRC values are not specified in the provided data; however, these grades are offered for hardened heavy-duty punch applications. In general, increasing wear resistance can reduce toughness, so select the grade that best matches your expected abrasion, edge loading, and lapping intensity.

Select dimensions by matching the punch tip geometry and shank fit to the punch holder and die land requirements. The provided shank diameter range is D = 3 ~ 25 mm; use the correct shank diameter tolerance class +0.005/0, m5 to achieve controlled seating in the holder.

• Tip selection: Choose the tip shape (Round, Rectangle, Oblong, Double Flatted Round, Radius Rectangle) and tip size parameters. Tip dimensions are given as P = 1 ~ 18 mm, with fine alterations PC = 0.5 ~ 9 mm, and corner radius R = 0.15 ~ 0.15 mm.
• Length matching: Head/overall geometry is defined through B (Tip length): L, S, X and L = 50 ~ 100 mm (multiple sub-ranges), plus full length alteration LC = 27 ~ 99.9 mm (range depends on the selected configuration).
• Tolerance considerations: Use the provided head thickness/total length tolerance change ranges: LCT and LMT to ensure stack-up matches your die height and lapping depth.

When integrating into tooling, verify that the holder’s bore and the die block thickness accommodate the chosen L / LC configuration and the specified shank fit tolerance.