The PDF buttons now download a construction kit: the plate, its shadow-casting piece, matching mounting marks and instructions. Both pieces use physical millimetres. Large pieces tile independently across ordinary A4 or Letter paper, with overlaps and calibration bars. The 2026-10-10 source verification records the fresh artifact checks performed before pushing this work.
Equatorial construction PDFs now include both faces and a gauge for the rod's exposed half-length. Their P- and O-prefixed sheets assemble separately on opposite sides of the same backing. Align the foot dots and target A before trimming; leave the stated rod length exposed on each side and add the backing's thickness to the whole rod. Printable example, hemisphere conventions and independent native measurements.
Try the two-page garden dial, or the actual browser downloads of a 300 mm circle in A4 and Letter. These examples are for latitude 45 degrees north, longitude zero, apparent solar time. The garden dial has a 90 mm radius; the circles have a 150 mm radius. Enter your own location before making a dial for use elsewhere.
This is a rendered PDF page, not a photograph of a physical build.
Print one-sided at Actual size / 100%, with Fit and additional poster tiling disabled. Measure every 100 mm bar and each tiled frame in both axes. The sheet assembly instructions explain trimming only the blank margins and retaining the 10 mm printed overlaps.
PDF download
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+-- Plate: compact sheet OR guide + R1C1, R1C2, ...
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+-- Gnomon: compact sheet OR guide + G-R1C1, G-R1C2, ...
Assemble the two groups separately, then mount the gnomon on the plate.
Reduced maps are not cutting templates.
On a triangular template, the filled dot marks the foot of the sloping shadow-casting edge. The open circle marks the other end of its base. Match those marks to the same marks on the plate; align the dashed base with the plate's dashed mounting line. Fold the tab 90 degrees so the triangle stands upright. Use flat backing, since the mounting tab can overhang a fan's point. The printed orientation tells you how to position the resulting dial.
The cross marks the nodus at a measured distance along the style from its foot. Add a small bead or notch there to cast a distinguishable shadow for the date curves. A printed ink cross does not create that shadow. The British Sundial Society's construction terminology explains the style, nodus and effects of gnomon thickness.
For a truly perpendicular style, the PDF provides a rod-length gauge, with the foot and nodus marked. The length is measured outward from the plate surface; any buried mounting length must be added separately.
At baseline cce5033, the triangular template held its base fixed while its
height grew as base * tan(angle). Near 90 degrees this made the template
enormous. Above 89.9 degrees, the renderer instead substituted a normal rod,
silently changing the angle. A separate inspection found that some wall
dials' mounting bases were outside their fan cuts.
| Reproduced case | Before | Current output |
|---|---|---|
| Horizontal, 89 N, radius 90 mm | SVG height 3234.15 mm | SVG height 103.80 mm; style angle remains 89 degrees |
| Horizontal, 89.91 N, radius 90 mm | Rod at 90 degrees | Exact 89.91-degree angle gauge, with a narrow-leg notice |
| Vertical, 45 S, wall -45 degrees, radius 90 mm | Base endpoint outside the cut | Base endpoint inside the expanded fan, with matching marks |
| Tall narrow wall fan, 89.91 S, wall +35 degrees, radius 235 mm | Compact PDF failed because mounting notes did not fit | Separate plate guide and full-size sheets |
| Browser PDF download | Plate only; separate SVG needed for the gnomon | Matching plate and gnomon in the same PDF |
The before/after measurements and original SVG files retain the first three reproductions. The tall narrow case is included in the current PDF matrix.
The new triangle is sized by a maximum base/rise envelope. For style angle
a, envelope s and nodus distance n:
style length = max(s / max(cos(a), sin(a)), n)
base = style length * cos(a)
rise = style length * sin(a)
The application uses s = 0.62 * radius and n = 0.32 * radius. Neither
hour geometry nor nodus coordinates change. The library's existing
gnomonBaseLengthMm input now sets the maximum of the two triangle legs;
a larger explicit nodus distance takes precedence. Returned baseLengthMm,
heightMm and styleLengthMm describe the actual piece. Only a perpendicular
style, within floating-point roundoff, becomes a rod.
The fan sector contains the mounting-base direction as well as the hour
rays. Its angular clearance still protects the end numerals. The mounting
line and markers are black engravings in the laser SVG; the outer cut stays
red. exportConstructionPDF is the new combined library export, while
exportPolarDialPDF remains available for a plate-only export.
scripts/verify-construction.py reads the actual SVG and PDF files. It does
not import the TypeScript geometry. It measures triangle legs, style length,
nodus position, plate mounting direction, cuts and scale bars, and checks that
the two pieces agree. It virtually stands each measured style upright on
the measured mounting line and compares its direction with a separately
constructed celestial-pole vector in local east/north/up coordinates.
For tiled styles it checks complete sheet grids, drawing coverage, clipping, repeated vector coordinates and paired registration targets. The existing plate verifier also checks numeral glyph containment and raster overlap agreement. These are digital measurements, not printer tolerances.
| Retained artifacts | Measured result |
|---|---|
| 26 PDFs, both paper sizes, 13 location/size/type combinations | 192 pages, including 42 style pages |
| Matrix sheet joins | 169 plate seams and 12 style seams |
| Largest style dimension discrepancy in PDF coordinates | Less than 0.00002 mm |
| Largest assembled-style axis discrepancy | Less than 0.000021 degrees in reconstructed geometry |
| Four actual Chromium/Firefox PDF downloads, with their SVG parts | 24 pages; all dimensions and mounting checks passed |
| Deliberately invalid kits | Rejected a 3% style shrink, a missing style tile, and an 89.91-degree style substituted for an 89-degree design |
The cases include both hemispheres, declining walls, a misplaced-base regression, near-normal and near-flat styles, poles, equatorial rods, 400 mm radius pieces and the tall narrow notes regression. Complete files and SHA-256 manifests are in matrix.zip and browser.zip. The detailed reports are matrix verification and browser verification.
The 3 mm warning and page-layout boundary were also exercised through 476 exports spanning radii 170-250 mm, seven latitudes, horizontal/declining-wall dials and both paper sizes. The initial pass found nine compact-plate note overflows; after reserving space for those notes, all 476 exports succeeded. This sweep checks successful generation, not fabrication accuracy.
Regenerate and measure the files from an installed checkout with Node 24
and uv:
node scripts/construction-fixtures.mjs test-results/construction
uv run scripts/verify-construction.py test-results/construction --check-controls --report test-results/construction-report.jsonOr inspect the retained bytes:
python -m zipfile -e docs/evidence/construction/matrix.zip test-results/retained-construction
uv run scripts/verify-construction.py test-results/retained-construction --check-controlsUse --render <directory> to save selected PDF pages as images. The pinned
Python readers are verification tools, not application dependencies. For
fresh browser downloads, run the production preview and
scripts/capture-prints.mjs as described in printing.md,
then use the construction verifier on its output directory.
A fresh detached checkout of 53dee8b was verified with Node 24.21.0 and
npm 11.19.0 on 2026-10-09:
| Command or workflow | Result |
|---|---|
npm ci, npm run lint, npm run typecheck |
Passed |
npm test, repeated with LC_ALL=de_DE.UTF-8 LANG=de_DE.UTF-8 |
269 passed in each locale |
npm run build, npx playwright test |
Production build; all 44 Chromium/Firefox workflows passed |
node examples/basic-horizontal-dial.ts |
Valid SVG; 53 hour lines and 3 declination lines |
| Regenerate and independently measure all 26 construction PDFs | All checks passed; all three invalid-kit controls rejected |
| Extract and remeasure the retained matrix and browser archives | Hashes, dimensions and assembly checks passed |
uvx ruff check scripts/verify-construction.py, uvx ruff format --check scripts/verify-construction.py |
Passed |
| Compare fresh Node 24 and working Node 26 production output | All 35 files have identical SHA-256 hashes |
| Fresh development server, browser PDF download | Correct download; no page errors |
The browser checks include asynchronous click-time snapshots, invalid-input recovery, near-normal angle gauges, rod templates, keyboard use, accessibility and phone layouts. The desktop capture, phone Export panel, full-size style pages and reduced maps were visually inspected. They retain the existing drawing-focused UI and show the complete kit's page count before download. Large template lettering in the thumbnail is small; the PDF provides the full-size drawing and readable instructions.
No physical print, folded assembly, cutter trial or outdoor reading has been performed. Thin-edge geometry does not compensate for material thickness, kerf, fold allowance, paper stretch or printer distortion. Building a thick gnomon changes the shadow geometry; the paper template does not correct it.
If either triangle leg is under 3 mm, the UI and PDF label it an angle gauge for a thin rigid style and require a separate support. This threshold is a construction heuristic, not a certified manufacturing limit. Very small angles may be impractical to reproduce accurately even with the correct drawing. The gauge does not promise a self-supporting paper triangle.
The app retains its 30-400 mm radius range. PDF work is capped at 64 full-size sheets per piece. Equatorial output is still the pole-facing face only; analemmatic dials still use SVG/PNG and a movable vertical gnomon. Long custom library notes can still be rejected when they exceed the available page.
Build with npm run build; the static site is written to dist/.
Nothing in this change has been pushed, released or deployed.