钢笔笔尖3d模型

一、图 → 结构描述（核心） 复制 fountain pen nib, elongated tapered shape, symmetrical geometry along central axis, sharp pointed tip, split nib with central slit, circular breather hole near upper middle, slightly curved convex surface, smooth continuous curvature from base to tip, rear section cylindrical connector, mechanical joint with housing, clean transition between nib and barrel, overall shape thin but structurally solid, balanced proportions, realistic writing instrument geometry  二、花纹描述（重点强化雕刻） 复制 ornamental engraved pattern on nib surface, symmetrical scrollwork and decorative lines, deep engraved grooves, physically carved into surface, engraving depth 0.4–0.8 mm, clear shadow inside grooves, V-shaped engraving channels, sharp edges, crisp line definition, no soft or shallow engraving, primary decorative curves thicker and deeper, secondary lines thinner and slightly shallower, engraving follows curvature of nib surface, high precision metal engraving style, luxury fountain pen