Custom Stroke Dice — a d20 + d6 you read by counting strokes

Custom Stroke Dice — d20 + d6

Two dice numbered in a custom stroke script rather than digits. Each face carries a centre line with strokes cut across it; where the strokes sit and how many there are gives the value.

You do not memorise twenty glyphs

The numbering decodes itself:

• strokes below the line — 1 to 5

• strokes above the line — 6 to 10

• strokes crossing at a slant / — 11 to 15

• strokes crossing square-on — 16 to 20

Read the stroke angle for the group of five, then count the strokes. That is the whole rule for the d20.

The d6 is simpler — it is a plain tally

The d6's face value is its stroke count: I, II, III, IIII, IIIII, IIIIII. Nothing to decode at all.

It works that way for a reason. A cube face rests in four orientations, so "above the line" and "below the line" are the same mark one half-turn apart — a d6 built on the four-group rule has a 1 and a 6 you cannot tell apart in the hand. Counting strokes is rotation-proof. (The d20 is fine: a triangular face only rests in three orientations, so its apex fixes "up" and no glyph is a rotation of another.)

Both dice are fair

• d20 — regular icosahedron, opposite faces sum to 21.

• d6 — right-handed (standard European) layout, opposite faces sum to 7.

Sizes

• d20: 22 mm edge, about 42 mm across the vertices — deliberately chunky, because five separated strokes need real estate inside a triangular face.

• d6: 18 mm across the flats.

Two ways to print

• Single colour — print custom_stroke_d20.stl / custom_stroke_d6.stl. The strokes are crisp recesses 0.6 mm deep, ready for paint-fill or an ink-and-wipe.

• Two colour (Bambu AMS) — print custom_stroke_d20_2color.stl / custom_stroke_d6_2color.stl. Each of those is ONE file holding two named solids. In Bambu Studio: Import → right-click → "Split to Parts", then assign one filament to body and one to strokes. Coordinates are preserved exactly, so the inlays land in their pockets.

Print settings

• 0.2 mm layers, no supports.

• The d20 needs a brim — it prints flat on a face, and the body is convex with roughly 48° lower overhangs, so the first layers are small.

• The d6 sits flat on a face natively; no brim needed.

• The strokes are 0.75 mm type. A 0.4 mm nozzle resolves them; a 0.6 mm nozzle will start to lose the gaps between adjacent strokes.