Su Changhe - Inch Finger Blade - Patriarch Version

A Quick Look at the 3D Printed 'Su Changhe - Inch Finger Blade - Patriarch Version'
Weapon Design
Origin: The unique hidden weapon of Su Changhe, the current 'Patriarch' of the Su family in the novel 'River of Darkness', named 'Inch Finger Sword/Inch Finger Blade', only three inches and seven fen long, as thin as a willow leaf, can be hidden between fingers, and can also be launched with internal energy.
Appearance Keywords: Willow leaf shape, single-edged slight arc, finger groove + blood groove, hidden 'Yama' seal script, black gold electric spark color scheme—these elements all need to be reflected during modeling.
Fastest Method: Download a 90 mm willow leaf throwing knife STL as a 'master model', use Blender/ZBrush to extend the finger groove, deepen the blood groove, and carve the 'Yama' seal script within 10 min to get the prototype of the Patriarch Version.
Recommended Printing Parameters
Resin printing 0.05 mm, 8K rigid resin, placed horizontally with the blade spine facing down, can reduce supports and ensure the thinnest 0.3 mm blade edge has no layering.
FDM Method: PLA-CF, 0.2mm layer, 100% infill, 0.4 mm blade edge, after printing, 2000 grit sanding → polishing → secondary quenching (80 ℃ hot water for 30 s) can improve strength.
Post-processing and Painting
Remove supports → wet sand 800-3000 grit → spray high-build primer → main color matte black → dry brush gunmetal → local dry brush metallic brown → use a 0.2 mm detail brush to dot dark red 'blood groove' → overall matte protective varnish.
If you want to create an 'internal energy' effect, you can reserve a 1 mm hole on the blade spine, thread a 0402 warm white LED + enameled wire, connect a 3 V button cell battery, and cover it with a layer of fluorescent resin. When lit, it will emit a dark gold electric glow.
Printing & Cost
A single 100 mm long blade, resin printing takes 25 min, resin cost about 0.8 RMB; printing 5 blades at different angles at once only takes 2 h.
Finger sheath assembly: Print a 1 mm thick 'finger ring sheath' with TPU 83 A, inner diameter adjustable from 16-20 mm, cost 0.3 RMB/piece, can hide 3 Inch Finger Blades between the index, middle, and ring fingers to achieve the 'hidden blade in palm' effect.
Summary
Although there is no ready-made 'Su Changhe - Inch Finger Blade - Patriarch Version' file yet, a slight modification of an existing willow leaf throwing knife STL can achieve a 1:1 restoration; with 0.8 RMB for resin printing + 30 min of post-processing, you can get a 3.7-inch hidden blade with black gold electric patterns and 'Yama' seal script, truly 'a sword hidden in the fingers', instantly bringing cosplay/photography/figurines to life.