OneCAD/docs/oracle.md

Reference tests

Generated by cargo xtask oracle. Each case in tests/oracle/ is a part described by our own recipe.json. SolidCraft replays the recipe through its command engine and compares the result with expected.json: body count, volume and area (relative tolerance 1e-3 unless the case states another), centre of mass and bounding box (within 1e-3 of the part's size), face count where the geometry fixes it, and, where the case has a reference.stl, the sampled symmetric (Hausdorff) distance between the two surfaces and the principal second moments of both triangulations. Every rebuilt part is also exported as STEP, validated and read back.

Where the expected values come from (the Source column):

• analytic: closed-form geometry worked out by hand (prisms, cylinders, cones, spheres, tori and Pappus' theorems, constant-radius fillets on straight edges, sheet-metal bends as annular sectors). The scripts in tools/oracle-analytic/ compute them and give the formulas.
• freecad <version>: the same recipe built with FreeCAD's public Python scripting API by tools/freecad-oracle/, an independent kernel run as an external program. FreeCAD is not a dependency of SolidCraft. Where the two kernels legitimately build a different shape (for example the corner patch where fillets meet), only volume and area are compared, within the tolerance the case states.

No expected value comes from a commercial CAD product.

76 / 76 cases pass; sources: 55 analytic, 21 freecad. 0 known failure(s) tracked in issues; 0 case(s) without expected values yet.

Case	Source	Result	Surface distance mm (max / mean)	Method	Notes
01-box	analytic	pass		box 40 x 30 x 20 from the origin: V = abc, A = 2(ab + bc + ca)
02-cylinder	analytic	pass		cylinder r=15 h=50 on XY: V = pi r^2 h, A = 2 pi r^2 + 2 pi r h
03-box-through-hole	analytic	pass		box 60x40x20 minus centred through cylinder r=6: V = abc - pi r^2 c, A = 2(ab+bc+ca) - 2 pi r^2 + 2 pi r c; hole is centred so the centroid stays at the box centre
04-revolve-vase	analytic	pass		revolve of a line/3-point-arc profile (XZ, x = radius, z = -sketch y) 360 deg about Z. Pappus/Green: V = 2 pi * int x dA, z_c = int x z dA / int x dA, A = sum over profile edges of 2 pi int x ds (bottom disk r20, frustum r20->25, torus zone of the arc (centre (-16.000000, 33.000000), R=41.109610), frustum r15->18, top disk r18)
05-taper-extrude	analytic	pass		square frustum: base 40 at z=0, top a1 = 40 + 230tan10 at z=30 (positive taper grows outward); V = h/3 (A0 + A1 + sqrt(A0 A1)), z_c = h (A0 + 2 sqrt(A0A1) + 3 A1) / (4 (A0 + sqrt(A0A1) + A1)), sides = 4 trapezoids (a0+a1)/2 * h/cos(10)
06-symmetric-extrude	analytic	pass		50 (x) by 20 (z) rectangle on XZ extruded +-15 along Y: box 50x30x20 centred at origin
07-fillet-all-edges	analytic	pass		box 40x30x20 with every edge rounded r=3 = inner box (34x24x14) grown by a ball r (Steiner): V = abc + 2r(ab+bc+ca) + pi r^2 (a+b+c) + 4/3 pi r^3, A = 2(ab+bc+ca) + 2 pi r (a+b+c) + 4 pi r^2; faces 6 planes + 12 quarter cylinders + 8 sphere octants
08-chamfer	analytic	pass		box 40x30x20 with the 4 top edges chamfered 2: lower box 40x30x18 + top slab with section (36+2u)x(26+2u) at depth u (V, moment by exact polynomial integration); A = bottom + sides(h=18) + top 36x26 + 4 trapezoid bevels of slant 2 sqrt2
09-shell	analytic	pass		50x40x30 box shelled inward 2 with the top open: box minus cavity [2,48]x[2,38]x[2,30]; A = outer bottom + outer sides + rim + cavity floor + cavity walls
10-rect-pattern-holes	analytic	pass		plate 90x70x5 minus 12 through cylinders r=3 at (15+20i, 15+20j), i<4, j<3: V = abc - 12 pi r^2 t, A = 2(ab+bc+ca) + 12(2 pi r t - 2 pi r^2)
11-circular-pattern-flange	analytic	pass		annulus R50/r15 h10 minus 6 through cylinders r=5 on a 40 radius: V = pi(R^2-r^2)h - 6 pi rh^2 h, A = 2 pi(R^2-r^2) + 2 pi(R+r)h + 6(2 pi rh h - 2 pi rh^2); 6-fold symmetry keeps the centroid on the axis
12-mirror-feature	analytic	pass		block [-30,30]x[0,30]x[0,10] + two bosses r=6 h=15 at (+-15,15) on top (mirror across YZ): V = abc + 2 pi r^2 h, A = 2(ab+bc+ca) + 2 * 2 pi r h
13-combine-join	analytic	pass		box [0,40]^2x[0,20] union cylinder r=12 at (40,20) z 0..40: V = box + half-cylinder (x>40, z<20, centroid 40 + 4r/3pi) + full cylinder z 20..40; A = bottom (1600 + pi r^2/2) + box top (1600 - pi r^2/2) + cyl top + 3 full sides + x=40 side minus 24x20 + cyl side (pi r 40 outside half + pi r 20 upper inside half)
14-combine-cut	analytic	pass		box [-25,25]^2x[-20,0] minus sphere r=15 at the origin (lower hemisphere removed): V = abc - 2/3 pi r^3, hemisphere centroid z = -3r/8; A = 2(ab+bc+ca) - pi r^2 + 2 pi r^2
15-combine-intersect	analytic	pass		cube [-20,20]^3 intersect sphere R=25: sphere minus 6 disjoint caps of height h=5 (caps cannot overlap: two would need x^2+y^2 > 800 > R^2); V = 4/3 pi R^3 - 6 pi h^2 (3R-h)/3, A = 4 pi R^2 - 6 * 2 pi R h + 6 pi (R^2-20^2)
16-sweep	analytic	pass		circle r=3 swept along line 30 (+Z) + tangent R20 quarter arc + line 30 (+X): two cylinders + quarter torus (Pappus: V = pi r^2 R theta, A = 2 pi r R theta; torus centroid at rho = (R^2 + r^2/4)/R * sin(theta/2)/(theta/2) from the bend axis along the bisector) + 2 end disks
17-loft	freecad 1.1.4	pass	0.013 / 0.0019 (worst at -7.9, -10.8, 31.2)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part.makeLoft
18-hole-features	analytic	pass		plate 60x40x15 minus: counterbore (r7 x 5 deep + r4 through), countersink (90 deg cone frustum r6->r3 over 3 mm + r3 through), blind r3 hole 10 deep to the shoulder with a 118 deg cone point (height 3/tan59, centroid 1/4 up from the apex); areas: removed top/bottom disks, cylinder walls 2 pi r h, cb floor annulus, cone laterals pi r s
19-l-bracket-constrained	analytic	pass		solved L: (0,0)-(60,0)-(60,8)-(8,8)-(8,40)-(0,40); area 60x8 + 8x32, extruded 20: V = A2 h, A = 2 A2 + perimeter*h, centroid of the two rectangles
20-slot-constrained	analytic	pass		obround: arc centres (0,0) and (40,0), R6, tangent horizontal lines y=+-6: A2 = 2rL + pi r^2, V = A2 h, A = 2 A2 + perimeter (2L + 2 pi r) h
21-draft	analytic	pass		40x40x30 box, 5 deg draft hinged on the bottom (z=0), pull -Z: square frustum 40 -> 40 + 230tan5; V = h/3 (A0 + A1 + sqrt(A0A1)), sides 4 trapezoids of slant h/cos5
22-split-body	analytic	pass		cylinder r20 z -30..30 split by the plane through the X axis tilted 30 deg (z = y tan30, stays within /z/<=11.6 inside the cylinder): 2 congruent halves (point symmetry), V total = pi r^2 h, A total = cylinder + 2 ellipses pi r (r/cos30)
23-bracket-multifeature	freecad 1.1.4	pass	0.007 / 0.0010 (worst at 57.3, 49.3, 25.8)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude join, Part makeFillet, Part extrude join, Part extrude cut, Part makeChamfer
24-user-parameters	analytic	pass		width 60 x depth 40 x height 15 block from the origin with a centred d10 through hole: V = (wd - pi r^2) h, A = 2(wd - pi r^2) + 2(w+d)h + 2 pi r h
25-sketch-triangle	analytic	pass		solved triangle (0,0), (50,0), P = t(cos60, sin60) with t = 25 + sqrt(150) from /P-(50,0)/ = 45 (the root nearest the drawn apex); V = (1/2 * 50 * Py) * 5, A = 2 A2 + perimeter*5, centroid = vertex mean
26-sketch-belt	analytic	pass		belt: convex hull of circles R20 @ (0,0) and r10 @ (50,0) (external tangents, sin a = (R-r)/d) minus the d8 hole at (50,0), extruded 5 as one body; hull area = (R+r) sqrt(d^2-(R-r)^2) + R^2(pi+2a)/2 + r^2(pi-2a)/2; moments by Green's theorem over the line/arc boundary
27-sketch-trapezoid	analytic	pass		solved trapezoid bottom (-30,0)-(30,0), top (-15,25)-(15,25) minus two d6 holes at (+-18, 8) (symmetric about the axis, 36 apart, 8 above l1); trapezoid centroid y = H(a+2b)/(3(a+b)); V = A2 t, A = 2 A2 + perimeter t
28-blind-pocket-fillets	freecad 1.1.4	pass	0.009 / 0.0015 (worst at 60.0, 15.1, 13.4)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude cut, Part makeFillet
29-two-sided-and-partial-revolve	analytic	pass		block [-20,20]x[-25,10]x[0,20] minus the 270 deg revolve (from +X towards +Y) of the 8x8 square r 4..12, z 12..20; the removed section is the annular sector minus the circular segment y > 10 (R^2 acos(d/R) - d sqrt(R^2-d^2), y-moment 2/3 (R^2-d^2)^1.5) that lies outside the block; sector moments (R^3-r^3)/3 (sin, 1-cos); A = box - top opening + floor - front-face notch 2 sqrt(44) x 8 + inner wall r th h + outer wall (th - pi + 2 asin(5/6)) R h + 2 end caps
30-fillet-after-shell	freecad 1.1.4	pass	0.008 / 0.0025 (worst at 56.3, 35.7, 3.5)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, makeThickness shell, Part makeFillet
31-fillet-l-all-edges	freecad 1.1.4	pass	0.009 / 0.0018 (worst at 7.9, 38.6, 18.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part makeFillet
32-boss-plate-fillets	analytic	pass		plate 60x60x8 + boss (r10, z 8..23) with R3 concave base and R2 convex top fillets taken as one solid of revolution: V, z-moment and lateral area from Pappus/Green on its (r,z) profile (quarter-circle fillet arcs); plate top loses the r13 disc
33-fillet-tangent-chain	analytic	pass		obround (R8, centres 40 apart) x 10 minus R2 fillet spandrel R^2(1-pi/4) and 1 mm chamfer triangle swept round the whole loop (Pappus: section x path of its centroid, inset R(10-3pi)/(3(4-pi)) resp. c/3); surfaces likewise (fillet arc centroid inset R-2R/pi)
34-chamfer-then-fillet	freecad 1.1.4	pass	0.009 / 0.0022 (worst at 38.5, 5.6, 19.9)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part makeChamfer, Part makeFillet
35-fillet-curved-curved	freecad 1.1.4	pass	0.011 / 0.0024 (worst at -9.5, 5.3, 14.6)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude join, Part makeFillet
36-corner-blend-two-radii	freecad 1.1.4	pass	0.012 / 0.0026 (worst at 45.4, 39.2, 26.5)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part makeFillet
37-pyramid-apex-blend	freecad 1.1.4	pass	0.020 / 0.0029 (worst at -0.0, 0.0, 28.4)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part.makeLoft, Part makeFillet
38-coincident-cylinders	analytic	pass		union of r10 z0..30 and r10 z20..50 = cylinder r10 h50: V = pi r^2 h, A = 2 pi r h + 2 pi r^2
39-tee-pipe	freecad 1.1.4	pass	0.008 / 0.0014 (worst at -9.7, 2.4, 40.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude join, Part extrude cut
40-box-sphere-torus	analytic	pass		box 60x60x10 (z -10..0) + upper hemisphere r12 + spherical cap h2 below z=-10 (V = pi h^2(3R-h)/3, A = 2 pi R h) - lower half torus R22 r4 (Pappus: V = pi r^2/2 * 2 pi R, centroid -4r/3pi, A = pi r * 2 pi R); top loses disc r12 and annulus 18..26, bottom loses disc r sqrt(44)	faces: bottom, 4 sides, top split by the groove into an annulus (r 12..18) and the outer part, upper sphere, lower cap, torus
41-tube-radial-holes	freecad 1.1.4	pass	0.010 / 0.0012 (worst at 1.9, 19.9, 24.8)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude cut, pattern (tools transformed and re-applied)
42-overlapping-patterns	freecad 1.1.4	pass	0.030 / 0.0010 (worst at -20.0, -0.0, 5.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude cut, pattern (tools transformed and re-applied), Part extrude cut, pattern (tools transformed and re-applied)
43-cut-splits-body	analytic	pass		two boxes 35x20x20 (x 0..35 and 45..80): V = 2abc, A = 2*2(ab+bc+ca)
44-shell-l-bracket	analytic	pass		L prism (area 736, perimeter 200) x 20 minus cavity = L shrunk by 2 (SolidCraft's intersection-join shell convention: inner faces offset by 2 and extended to meet, sharp inner corner at (6,6); area 352) from z=2 to 20. A rounded (arc) join would give V 8368.5487, A 8768.5487, 16 faces
45-shell-boss-plate	analytic	pass		plate 60x60x10 + boss r12 h20 minus cavity (box 56x56x8 + cylinder r10 z8..28) under SolidCraft's intersection-join shell convention (offset faces extended to meet: sharp circular inner edge at r10, z8). A rounded (arc) join would give V 13620.2567, A 14104.4455, 16 faces (torus round r2)
46-shell-two-open-faces	analytic	pass		box 50x40x30 minus cavity x3..47, y0..37, z3..30 (3 mm walls, top and front open)
47-draft-curved-pocket	freecad 1.1.4	pass	0.008 / 0.0019 (worst at 22.1, 21.3, 15.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude cut, PartDesign Draft
48-pulley	analytic	pass		revolve of the 12-segment (r,z) polygon about Z: V = 2 pi int r dA, Mz = 2 pi int r z dA, A = 2 pi int r ds (Pappus)
49-helical-sweep	analytic	pass		true helix coil (screw motion of the axial d4 section, R20, pitch 8, 3 turns): V = turns * 2 pi R * pi a^2; lateral A = turns * 2 pi * int sqrt(r^2 + (p/2pi)^2 (dr/ds)^2) ds (periodic trapezoid, exact to round-off) + two end discs; COM z = pitch*turns/2
50-sweep-tight-bend	analytic	pass		tube r5 along line 20 + R5 quarter bend + line 20: V = pi r^2 L, A = 2 pi r L + 2 pi r^2 (Pappus, valid while bend radius >= r; here equal so the inner side pinches to a line); bend centroid at (R^2 + r^2/4)/R * sinc(pi/4) along the bisector
51-loft-rect-circle-offset	freecad 1.1.4	pass	0.025 / 0.0030 (worst at -11.7, 15.0, 0.4)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part.makeLoft
52-circular-pattern-fillet	analytic	pass		disc r40 h8 + 6 x (boss r6 h10 with R2 concave base fillet as a solid of revolution, Pappus/Green on its (r,z) profile) at radius 28; disc top loses 6 discs r8
53-path-pattern	analytic	pass		plate 120x60x5 minus 7 through holes d6 at arc lengths k*17.875031 along the arc through (100,15),(60,45),(20,15) (centre (60,10/3), R 125/3), translated copies
54-mirror-body-fillets	analytic	pass		prism h10 of the 60x40 rectangle with four R5 corner rounds and two d8 holes at (+-15,20): V = A h, area = 2A + perimeter*h
55-tapped-hole-cosmetic	analytic	pass		plate 40x30x15 minus d6.8 cylinder 12 deep (to the shoulder) and 118 deg drill point cone (h = r/tan59, V = pi r^2 h/3, lateral pi r * r/sin59); cosmetic thread adds no geometry
56-holes-on-curved-face	freecad 1.1.4	pass	0.009 / 0.0018 (worst at -16.9, 18.5, 0.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, hole tool (cylinder/cone) cut
57-hole-pattern-sketch-points	analytic	pass		plate 80x50x10 minus 6 counterbored through holes (cb d10 x 5.5, hole d5.5) at x 15/40/65, y 15/35
58-phone-stand	freecad 1.1.4	pass	0.007 / 0.0010 (worst at 82.5, 11.7, 6.1)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part makeFillet, Part extrude cut
59-enclosure-base	freecad 1.1.4	pass	0.008 / 0.0017 (worst at 90.9, 51.0, 6.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part makeFillet, makeThickness shell, Part extrude join, Part extrude cut
60-pipe-flange	freecad 1.1.4	pass		FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part revolve, Part extrude cut, pattern (tools transformed and re-applied), Part makeChamfer, Part makeFillet	No reference.stl: over 409600 bytes even at 0.02 mm deflection (11380 facets).
61-shaft-keyway	freecad 1.1.4	pass	0.008 / 0.0019 (worst at 11.9, 3.9, 45.8)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part revolve, Part makeChamfer, Part extrude cut
62-heat-sink	analytic	pass		base 60x50x5 + 15 fins 1.5x50x25 at x = 2 + 4k: sums of boxes; fin ends coplanar with the base ends	faces: bottom, x=0, x=60, y=0 and y=50 (each merged with the fin ends), 16 base-top strips, 15x3 fin faces
63-hinge-knuckle	freecad 1.1.4	pass	0.008 / 0.0016 (worst at 28.0, 36.9, 4.7)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Part extrude, Part extrude join, Part extrude cut
64-sketch-tangent-arc-chain	analytic	pass		solved sketch: 80x20 rectangle whose top is 4 tangent R12 arcs on 20 mm chords alternating up/down (net area 1600); prism h3: V = A h, area = 2A + perimeter*h, Green's theorem for centroid
65-sketch-gear-tooth	freecad 1.1.4	pass	0.008 / 0.0017 (worst at 6.5, 39.5, 8.0)	FreeCAD (OpenCASCADE) build of recipe.json by tools/freecad-oracle/build.py: Sketcher-solved sketch, Part extrude
66-sketch-linkage	analytic	pass		solved sketch: hull of circles R12 at (0,0) and R8 at (60,0) (outer tangent lines, cos a = 4/60) minus holes d12, d8 (concentric) and d4 at (30,+-4) (symmetry keeps radii equal); prism h6
67-sm-base-flange	analytic	pass		plate 100 x 60 x t, t = 2.5 (Steel (mm) rule), thickness along +Z: V = 10060t, A = 2(ab+bc+ca)
68-sm-edge-flange	analytic	pass		extrusion along x (100) of the YZ section: base y 5..60 x t; 90 deg bend annulus R 2.5..5 about (y 5, z 5); flange y 0..2.5, z 5..20. Setback (R+t)tan45 = 5 (inside bend position, outer-face height datum: outer face of flange reaches z = 20); V = L*A_sec, A = 2 A_sec + L P_sec	trim/setback and height datum are SolidCraft's documented edge-flange conventions (sheet.rs add_flanges)
69-sm-tray	analytic	pass		tray: base 90 x 50 x 2.5 (each edge trimmed by the setback 5); four 90 deg bends R 2.5..5 along the trimmed edges (90, 50, 90, 50 long); four walls 2.5 thick, z 5..25, each running on past its bend by ext = (R+t) - (t + gap/sqrt2) = 0.732233047 at both ends; open corners. A = sum of prisms - 2 x joints	corner treatment is SolidCraft's convention (sheet.rs close_corners: panels extended until their inner corners are the rule gap = t apart; no corner fill, open corner relief below the walls)
70-sm-flange-45	analytic	pass		as 68 with a 45 deg bend: setback (R+t)tan22.5 = 2.071068, base y 2.071068..60, bend annulus 2.5..5 over 45 deg about (y 2.071068, z 5), flat leg 15 - setback = 12.928932 turned 45 deg; extrusion along x 100	SolidCraft convention: flange height (15) is measured along the flange's outer face from the virtual sharp at the original edge (y 0, z 0), so the outer top corner is at (y, z) = (-15 cos45, 15 sin45).
71-sm-custom-rule	analytic	pass		U channel, rule t 1.5, R 3, K 0.33 (K unused folded): base y 4.5..45.5 x 1.5; two 90 deg bend annuli R 3..4.5; flanges y 0..1.5 and 48.5..50, z 4.5..20; extrusion along x 80	the rule edit applies to the whole sheet body (base built before it is 1.5 thick too, as the recipe's edge picks at z = 1.5 state)
72-sm-contour-flange	analytic	pass		contour flange, width 50 along +Y, XZ section: plate x 0..35 z 0..2.5; bend R 2.5..5 about (35, 5) (sketch corner = outer virtual sharp, setback R+t); wall x 37.5..40 z 5..27.5; bend R 2.5..5 about (42.5, 27.5) (sketch corner = inner virtual sharp, setback R); plate x 42.5..70 z 30..32.5	SolidCraft convention: the sketch lines are the sheet face away from the material (material right of travel); thickness grows to the material side
73-sm-hem	analytic	pass		68's part (height 20) plus a flat hem on the flange top edge: 180 deg bend, inner radius = hem gap 0.01, outer 2.51, about (y 2.51, z 20), folded toward +y (inside); hem leg 8 - (0.01 + 2.5) = 5.49: y 2.52..5.02, z 14.51..20; extrusion along x 100	SolidCraft conventions: hem gap 0.01 mm (rule hem_gap), hem length measured to the outer face of the hem bend (top at z 22.51), hem folds over the flange's inner face.
74-sm-unfold-refold	analytic	pass		U channel 80x50 (t 2.5, R 2.5, base y 5..45, flanges z 5..20) with the flat-pattern slot x 35..45, y -12..10 refolded: BA = (pi/2)(R + K t) = 5.654866776, so the slot removes base y 5..10, the whole y=0 bend and the flange from z 5 to 5 + (12 - (BA - 5)) = 16.345133224; x-segments 0..35 / 35..45 / 45..80	unfold/refold maps flat distance through the K-factor neutral layer (K 0.44)
75-sm-bracket-holes	analytic	pass		base x 0..75, y 5..40, z 0..2.5 (trimmed 5 by each flange's setback); bend 1 (R 2.5..5 about y 5, z 5) x 0..75; flange 1 y 0..2.5, z 5..30, x 0..80; bend 2 (R 2.5..5 about x 75, z 5) y 5..40; flange 2 x 77.5..80, z 5..15, y 5..40; minus two d6 through holes at (25,20), (55,20) in the base. A = sum of prism areas - 2 x 4 joint areas (75t, 75t, 35t, 35t) + hole walls - hole discs	SolidCraft convention: the second flange trims the base under the first bend, so bend 1 stops at x 75 while flange 1's panel runs to x 80 (open corner relief, no fill).
76-sm-thickness-variant	analytic	pass		final rule thickness 3 (bend radius = Thickness = 3): base y 6..60 x 3; bend annulus R 3..6 about (y 6, z 6); flange y 0..3, z 6..20; extrusion along x 100	the rule's thickness edits regenerate the whole sheet body; only the final 3 mm state matters

Not covered by a reference case

Feature	Tested by
Boss (draft, root fillet, hole, ribs)	post, hole and rib volumes (boss_with_hole_fillet_and_ribs)
Lip / Groove	band offsets and groove clearance on a shelled box (lip_and_groove_on_a_shelled_box, groove_takes_the_rule_clearance)
Snap Fit	arm and catch volume, hook direction (snap_fit_arm_and_catch)
Rest	rectangle, round, hollow and drafted pads (rest_pads)
Plastic Rules (manage, assign)	library values, Thickness-based values, rule draft as the boss default (plastic_rules_library_edit_and_assign)