Reference
Parametric Gasket CAD Generator
What every field does and what ends up in each file.
The gasket DXF generator builds every gasket from a handful of numbers with exact lines and arcs, then checks it the way a machinist would: bolt chord, the web around each hole and whether it fits the sheet or printer bed. This page lists all parameters, the five DXF layers and the formats in the free and Pro exports.
Shapes
The five shapes and their parameters
All lengths in mm internally; inch mode converts at exactly 25.4.
| Shape | For | Parameters and ranges | Checks | Example |
|---|---|---|---|---|
| Circular pipe flange | Full-face pipe, pump and valve gaskets | OD 10–2000, ID 0 to OD − 4, PCD between ID + d and OD − d, 2–36 holes Ø1–100, start 0–360° or straddle, pull tang 5–80 × 5–80 mm | Webs: hole → bore, hole → outer edge, between holes | Load |
| 2/3/4-bolt exhaust & carb flange | Manifold, header, collector and carb spacer gaskets | Bore 5–300, 2–4 bolts, spacing / PCD 10–500, hole Ø2–30, slot 0–20, ear R3–60, body margin 1–50, start 0–360° | Webs: bore → edge, slot → bore, slot → ear edge, between holes | Load |
| Rectangular / oblong cover | Gearbox, crankcase, valve and junction-box covers | L and W 20–1500, wall 2–100, corner R, inner R auto, even or per-side 0–60 holes Ø1–40, boss R0–40, offsets, passage | Webs: hole → band edge, passage → band edge, between holes | Load |
| 4-barrel carburetor base | Carb, throttle body and spacer plates | Plate 30–400, corner R0–50, 1/2/4 ports Ø5–120 at pitch X/Y, 4 studs Ø2–20 at pitch X/Y | Webs: stud → edge, port ↔ port, port → stud, port → edge | Load |
| Large split-ring dovetail | Rings larger than the sheet, bed or laser | Circular parameters + 2–16 segments dividing N, dovetail clearance 0–0.50 mm per side | Webs on the uncut ring; segment box and 256 mm bed check | Load |
DXF
The 5-layer DXF structure
AutoCAD R12 ASCII (AC1009), nominal geometry, true circles and bulge arcs.
| Layer | Colour | Contents | Cut |
|---|---|---|---|
| OUTER_CUT | ACI 4 cyan | Outer profile incl. pull tang, ears, bosses, dovetail tabs | Cut last |
| INNER_BORE | ACI 7 white | Centre bore, inner opening, ports, oil/water passages, traced inner contours | Cut first |
| BOLT_HOLES | ACI 30 orange | Every bolt hole as a CIRCLE (slots as closed bulge POLYLINE) | Cut first |
| CENTERLINES | ACI 3 green, CENTER linetype | PCD circle, hole cross lines, band centreline, dovetail joint lines | Do not cut |
| DIMENSIONS | ACI 8 grey | OD/ID/PCD/hole dimensions, title text | Do not cut |
Construction
How each shape is built
Exact lines and arcs, so areas, webs and the DXF agree to the micron.
- Circular flange — a disk of the OD united with the optional pull tang (a straight tab with a semicircular tip), minus the bore and the bolt-hole circles.
- Exhaust / carb flange — the convex hull of a circle around the bore (bore/2 + body margin) and one circle per ear, joined by tangent lines; holes are circles or radial slots.
- Cover — the band between two rounded rectangles united with a boss circle at every hole, minus the holes and the passage; the inner opening is cut back where a boss reaches into it.
- Carb base — a rounded plate minus 1, 2 or 4 ports and four stud holes.
- Split ring — the circular ring cut into segments along radial joints halfway between bolts, each joint carrying a dovetail tab on one segment and a matching socket, enlarged by the clearance, on the next.
Because every edge stays a true line or arc, the area is exact rather than counted from pixels: the ASME 4-inch gasket with its tang is 289.4 cm², which at 3 mm and 1.8 g/cm³ is 156.3 g of aramid fibre.
What the free TXT does and does not contain
The check sheet lists the shape and standard, every size parameter, the bolt pattern and chord, each web with its location, thickness, material, area, weight and kerf, then one row per hole with its angle, radius and X/Y. It never contains outline vertices, traced polylines, slot or boss geometry — it is a checking document, not a way to rebuild the cutting file.
Rules
Minimum web and kerf rules
The web is the material between a hole (or passage, port, slot) and the nearest boundary. Each shape measures the webs that can actually fail — listed in the shape table — and shows the smallest one with where it is. Under 2.5 mm the studio shows THIN WARNING and draws that web red in 2D and 3D.
Kerf offset k is half the cut width. In the SVG, outer contours move out by k and every inner contour moves in by k; the DXF stays nominal and states k in a note. Valid range 0.00–0.60 mm.
Files
File formats in the free proof and the Pro pack
| File | Format | Contents |
|---|---|---|
| {slug}-proof.png (free) | PNG ≤ 1000 px | Blueprint at a non-integer scale, diagonal watermark, PROOF ONLY banner, no DPI |
| {slug}-specs.txt (free) | Plain text | Parameters, chord, webs, area, weight, kerf and one row per hole: angle, radius, X, Y — no outline vertices |
| {slug}.dxf (Pro) | DXF R12 ASCII | 5 layers, CIRCLE holes, bulge polylines, dimension callouts |
| {slug}-cut.svg (Pro) | SVG, width/height in mm | Kerf-compensated cut paths: blue inner first, red outer last |
| gasket_tpu_part.stl (Pro) | Binary STL, mm | Closed extrusion of thickness t with optional 0.3 mm beads |
| silicone_casting_mold.stl (Pro) | Binary STL, mm | Base with cavity, cores, 4 pins; 4 mm lid with sprue and 2 vents |
| {slug}-1to1-template.pdf (Pro) | Vector PDF 1.4 | Check page with 50.0 mm / 2.00 in squares, 1:1 tiles with crosshairs and targets |
The file name slug is shape, size and hole count, for example circular-flange-228p6x114p3-8h for the ASME 4-inch gasket. Tiling rules are on the template PDF page and chord math on the bolt circle calculator.