Making Your Own Dapping Blocks and Forming Punches
自制窝砳与成型冲的工具钢处理
标签：自制窝砳, 工具钢, 硬度搭配, 成型冲
自制窝砳常用 45 钢或 S7：窝腔车削后内壁抛到 Ra 0.4 以下再淬火，硬度控制在 HRC 45–50——太硬会啃伤退火态铜面，太软则窝口翻卷变形；配套成型冲端部淬硬到 HRC 55–58，与砳保持约 5 个 HRC 的硬度差，磨损集中在可更换的冲上。窝口缘倒 R1 以上圆角防止切料。最后一道精整建议用未淬火的聚碳酸酯或硬木冲，可彻底避免金属锤痕。每件自制砳须在侧面打窝径与深度钢印，公差 ±0.1 mm。
For self-made dapping blocks use 1045 steel or S7: turn and polish the cavities below Ra 0.4 before hardening to HRC 45–50—harder gouges annealed copper, softer lets the cavity rim roll over. Harden the mating punch tips to HRC 55–58, keeping about 5 points of hardness difference so wear lands on the replaceable punch. Round every cavity lip R1 or better to stop edge biting. For the final smoothing pass use an unhardened polycarbonate or hardwood punch, which leaves no hammer marks at all. Stamp each block with cavity diameter and depth to ±0.1 mm.