Add dog-bone configuration and fix svg export size

.tool-versions

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+nodejs lts

README.md

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+# Torsion box table generator
+
+A browser tool that draws a CNC-cuttable torsion box table and hands you the SVG.
+You give it the finished size of the tabletop and the thickness of your sheet
+stock; it works out the egg-crate frame underneath, nests every part on the
+sheet, and exports the lot at real-world scale ready to cut.
+
+It also knows about the [Lowrider 4](https://docs.v1e.com/lowrider/) CNC, and
+will add the rails, the track cut-outs and the clips that hold them down. Set
+the configuration to "No machine" and you get a plain torsion box table.
+
+Live at <https://avec-sans.github.io/torsion-box-table/>. It runs entirely in
+the browser — nothing is uploaded — and every push to `main` republishes it.
+
+## How it works
+
+Everything is derived from a handful of numbers, so there is nothing to draw by
+hand:
+
+- **Spar spacing** is a *maximum*. Say you never want spars more than 12in apart
+  and the generator fits as many as that needs, then divides the space evenly —
+  so the real spacing usually comes out a little tighter than you asked for.
+- **Slots** are cut as wide as your material and half the thickness deep, from
+  the top edge on the X spars and the bottom edge on the Y spars, so the two
+  sets drop into each other.
+- **Dog-bones** are added automatically to every inside corner, sized from your
+  bit diameter, so a round cutter still leaves a corner a square part can seat
+  into. They use the [minimal 45° relief](https://fablab.ruc.dk/more-elegant-cnc-dogbones/):
+  the least material removed that still lets the joint close. Set the bit
+  diameter to 0 to switch them off.
+- **Nesting** lays every part out on one sheet with a clear margin between them,
+  wide enough for the cutter to pass without touching either part.
+
+## The 3D view
+
+"Show 3D view" swaps the cut sheet for the assembled table — spars slotted
+together, rails and spoilboard in place — built from the same numbers as the
+drawing, so it is a check on the parameters rather than a separate model. Drag
+to orbit, right-drag to pan, shift + right-drag to spin it about the vertical
+axis, scroll to zoom. Individual parts can be hidden to see inside the frame.
+
+It is a preview only; the SVG is still what you cut. three.js is a large
+download, so it is only fetched the first time you open the view.
+
+## Cutting one
+
+1. Set your units and configuration, then work down the settings in the sidebar.
+2. **Download the SVG and cut the calibration square first.** It is in the
+   bottom corner of the sheet. Measure it — it should come out at exactly the
+   size the sidebar says. If it does not, your CAM is scaling the file and
+   nothing else will fit.
+3. **Cut the test parts**, the two small pieces next to the calibration square.
+   They are one X-spar slot and one Y-spar slot in your real material. Push them
+   together: if they bottom out in the slot instead of pulling tight face to
+   face, raise the **spar slot overcut** and re-cut them. If they are loose side
+   to side, that is the material thickness setting, not the overcut.
+4. Cut the sheet.
+
+Parameters are saved in your browser as you go, so the table you were working on
+is still there next time. **Export JSON** writes them to a file you can keep
+alongside the cut, or hand to someone else to import.
+
+## Settings
+
+| Group | What it covers |
+| --- | --- |
+| Machine | Lowrider 4 or a plain table, and the units everything else is given in. Switching units converts the values you have already entered. |
+| Material | Your sheet thickness, the cutter, and the space left between parts on the sheet. |
+| Table size | The finished tabletop. The frame is inset from these by the overhang on every side. |
+| Spars | Maximum spar spacing, and the overcut that sets how much clearance is left at the bottom of the slots where spars cross. |
+| Rails | Rail stock, the longest piece your machine can cut in one go before a rail is split in two, and clip spacing. Lowrider 4 only. |
+| Track fit | Padding on the flat and tube track cut-outs. Increase if the machine binds on the rails, decrease if it has play. |
+
+Units are converted differently depending on what a number is for. Cut
+dimensions round *up* to something you can actually cut — a whole millimetre, or
+a sixteenth of an inch. Fit settings (bit diameter, overcut, part margin, track
+buffers) are too small to survive that, so they convert exactly.
+
+## Development
+
+Requires Node LTS. [Bun](https://bun.sh) is what CI uses, but npm works.
+
+```sh
+npm install
+npm run dev      # vite dev server
+npm run build    # typecheck and build to dist/
+npm run lint
+```
+
+Pushing to `main` builds and deploys to GitHub Pages via
+[.github/workflows/deploy.yml](.github/workflows/deploy.yml).
+
+### Layout
+
+- `src/models/Table.ts` — every dimension, and the derived geometry (spar counts
+  and spacing, slot depth, dog-bone radius, unit conversion). Almost all the
+  real logic lives here.
+- `src/components/` — one component per part (`XSpar`, `YSpar`, `TopRail`,
+  `SideRail`, `TestParts`, `CalibrationSquare`), each emitting an SVG path from
+  a `Table`. `TableLayout` nests them on the sheet; `TableEditor` is the
+  sidebar.
+- `src/components/Table3DView.tsx` — the 3D view, react-three-fiber over
+  three.js. It builds its own meshes from the same `Table` getters rather than
+  sharing geometry with the SVG components, so a change to how a part is cut has
+  to be made in both places. `App.tsx` lazy-loads it.
+- `src/lib/dogbone.ts` — the corner relief, shared by every part.
+- `src/lib/storage.ts`, `src/lib/filename.ts` — browser persistence and export
+  naming.
+
+Adding a new dimension means adding it to `TableEditable`, `tableNumericFields`
+and the constructor in `Table.ts`, plus a label in `TableEditor.tsx`. Snapshots
+are read and written by field name, so import, export and saved settings pick it
+up on their own, and a config saved before it existed still loads.
+
+## Credits
+
+Originally made by [Zach Zundel](https://github.com/3ach/table). The 3D view is
+the work of [jeyeager65](https://github.com/jeyeager65), ported from
+[their fork](https://github.com/jeyeager65/table). This version by
+[avec sans](https://github.com/avec-sans/torsion-box-table).

index.html

@@ -3,7 +3,7 @@
   <head>
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>Table</title>
+    <title>Lowrider4 Torsion Box SVG Table Generator</title>
   </head>
   <body>
     <div id="root"></div>