DXF Part Maker: Gear, Sprocket, Flange & Plate DXF Generator
Pick a part, type the sizes and watch it update. Download a clean DXF or SVG for your laser, plasma, waterjet or router. Everything runs in your browser.
1. Part type
mm
Thickness is not drawn. It is used to warn about holes and webs that are too small to cut well.
2. Plate size
Positions are measured from the bottom-left corner of the plate. Chamfer size is the leg length along each edge.
Holes and slots
2. Flange or gasket
2. Spur gear
mm
Backlash thins each tooth by this much on the pitch circle. A common total is 0.04 to 0.1 × module, split between the two gears.
Bore
2. Roller chain sprocket
Tooth form: ANSI B29.1 (seating curve, working curve, straight line and topping curve).
Bore
2. Washer, spacer or shim
Bolt holes (optional)
3. Export options
Off by default so the CENTER lines are not cut by mistake.
Live Preview
Drag to pan, scroll or pinch to zoom.
OUTLINE
HOLES
CENTER
Origin 0,0
Checks
Key sizes
How the DXF Part Maker Works
The part maker draws common flat parts from a few sizes. It works out the geometry with the standard formulas, checks that the part can be made, and writes a DXF or SVG file ready for CAM.
Outlines are single closed polylines. Straight edges are lines and round edges are true arcs (polyline bulges), so the file stays small and cuts smoothly. Holes are circles. Slots and keyed bores are closed polylines. Gear flanks are the only curves made of short lines, and they stay within 0.002 mm (0.0001 in) of the true involute. Everything happens in your browser.
The Method
1. Plate or bracket
A rectangle with square, radius or chamfer corners. Add any mix of single holes, hole grids, bolt circles and slots. A grid is centred on the plate or set by its edge distance. Bolt circle holes sit at x = cx + (PCD/2)·cos(θ0 + 360°·k/n). A slot's length is its overall length, end to end.
2. Flange or gasket
Presets come from ASME B16.5 Class 150 (flange OD, bolt circle, bolts, hole size) and EN 1092-1 PN16 (D, K, n, L). Ring gaskets for ASME use the ASME B16.21 sizes; their OD equals the bolt circle minus the bolt size, so they centre on the bolts. Bolt holes straddle the centre lines, so the first hole sits at 180°/n. Every value can be edited.
3. Spur gear
d = m·z da = m(z + 2 + 2x) df = m(z − 2.5 + 2x)
db = d·cos α s = m(π/2 + 2x·tan α) − backlash
The tool rolls a standard basic rack (addendum 1.0 m, dedendum 1.25 m, tip radius 0.38 m, as in ISO 53) around the gear, the way a hob cuts it. The flanks come out as true involutes and the root fillet is the trochoid the rack tip leaves. So small tooth counts show real undercut. For DP, m = 25.4 ÷ DP. The tool warns below zmin = 2 ÷ sin²α (17 teeth at 20°, 32 at 14.5°, 12 at 25°) unless the profile shift is big enough.
4. Roller chain sprocket
PD = P ÷ sin(180°/N) OD = P(0.6 + cot(180°/N))
Bottom dia = PD − Dr Caliper (odd N) = PD·cos(90°/N) − Dr
The teeth follow the ANSI B29.1 tooth form as set out in Machinery's Handbook. Seating curve R = 0.5025 Dr + 0.0015 in, then a working curve E = 1.3025 Dr + 0.0015 in through angle B = 18° − 56°/N, a straight line yz, and a topping curve F up to the OD. All are true arcs. ISO 606 B-series chains use the same form with the inch constants converted. ISO 606 allows a range of tooth forms, so check its limits if you need them.
5. Washer, spacer or shim
Round or rectangular, with an inside diameter or an open U-slot from the bottom edge (a slotted shim). The slot depth is measured from the edge to the end of the round. You can add bolt holes on a circle.
6. Bores, keyways and checks
Keyways follow DIN 6885-1 (hub depth t2 past the bore) or ANSI B17.1 square keys (nominal, half the key height at the side wall), or your own width and depth. Every hole and slot is checked: it must sit inside the material and not touch another cut. If it does, the part shows an error and the download waits. Give a material thickness to also get warnings on small holes and thin webs.
Worked Examples
These numbers were measured from files made by this tool, read back with the ezdxf library.
Spur gear: module 2, 20 teeth, 20°
- Pitch diameter 2 × 20 = 40 mm. Outside 2 × 22 = 44 mm. Root 2 × 17.5 = 35 mm. Base 40 × cos 20° = 37.588 mm.
- Tooth thickness on the pitch circle should be πm/2 = 3.1416 mm. The flank points lie on the true involute to within 0.000001 mm. Measured across the drawn polyline it is 3.1413 mm (the tiny chord sag).
- The outline reads back with smallest and largest radius of exactly 17.500 and 22.000 mm.
- At 10 teeth the tool warns about undercut and says a shift of 0.42 fixes it. With x = 0.45 the OD becomes 25.8 mm and the root 16.8 mm.
Sprocket: #40 chain, 20 teeth
- Pitch 0.500 in, roller 0.312 in. Pitch diameter 0.5 ÷ sin 9° = 3.1962 in.
- Outside 0.5 × (0.6 + cot 9°) = 3.4569 in. Bottom 3.1962 − 0.312 = 2.8842 in.
- Arcs in the file: seating R 0.1583, working E 0.4079, topping F 0.2572 and the OD land 1.7284 in.
- With 21 teeth the caliper diameter is 3.3548 × cos(90°/21) − 0.312 = 3.0334 in.
Flange: ASME B16.5 Class 150, NPS 4
- OD 9.00 in, bolt circle 7.50 in, 8 holes Ø0.75 in, first hole at 180° ÷ 8 = 22.5°.
- Hole spacing (chord) 7.5 × sin(22.5°) = 2.870 in. Bore set to the 4.500 in pipe OD.
- Matching B16.21 ring gasket: 4.50 × 6.88 in. 7.50 − 5/8 in bolt = 6.875 in, so it centres on the bolts.
Plate: 150 × 100 mm, R10 corners
- Ø30 centre hole, 2 × 2 grid of Ø9 holes at 120 × 70 mm pitch (15 mm from each edge), 6 × Ø6.6 on a 60 mm bolt circle and a 40 × 8 mm slot.
- The four corner arcs read back as R10.000 and the slot ends as R4.000. The slot is exactly 40 × 8 mm.
- Move a hole into a rounded corner or onto another hole and the tool flags it and holds the download.
Standard Tables Used
Values as published in the standards named. Check them against your copy of the standard, and the flange you are mating to, before cutting.
ASME B16.5 Class 150 flanges and ASME B16.21 ring gaskets (inches)
| Size | Flange OD | Bolt circle | Bolts | Hole dia | Pipe OD | Ring gasket ID | Ring gasket OD |
|---|---|---|---|---|---|---|---|
| NPS 1/2 | 3.50 | 2.38 | 4 | 0.62 | 0.840 | 0.84 | 1.88 |
| NPS 3/4 | 3.88 | 2.75 | 4 | 0.62 | 1.050 | 1.06 | 2.25 |
| NPS 1 | 4.25 | 3.12 | 4 | 0.62 | 1.315 | 1.31 | 2.62 |
| NPS 1-1/4 | 4.62 | 3.50 | 4 | 0.62 | 1.660 | 1.66 | 3.00 |
| NPS 1-1/2 | 5.00 | 3.88 | 4 | 0.62 | 1.900 | 1.91 | 3.38 |
| NPS 2 | 6.00 | 4.75 | 4 | 0.75 | 2.375 | 2.38 | 4.12 |
| NPS 2-1/2 | 7.00 | 5.50 | 4 | 0.75 | 2.875 | 2.88 | 4.88 |
| NPS 3 | 7.50 | 6.00 | 4 | 0.75 | 3.500 | 3.50 | 5.38 |
| NPS 3-1/2 | 8.50 | 7.00 | 8 | 0.75 | 4.000 | 4.00 | 6.38 |
| NPS 4 | 9.00 | 7.50 | 8 | 0.75 | 4.500 | 4.50 | 6.88 |
| NPS 5 | 10.00 | 8.50 | 8 | 0.88 | 5.563 | 5.56 | 7.75 |
| NPS 6 | 11.00 | 9.50 | 8 | 0.88 | 6.625 | 6.62 | 8.75 |
| NPS 8 | 13.50 | 11.75 | 8 | 0.88 | 8.625 | 8.62 | 11.00 |
| NPS 10 | 16.00 | 14.25 | 12 | 1.00 | 10.750 | 10.75 | 13.38 |
| NPS 12 | 19.00 | 17.00 | 12 | 1.00 | 12.750 | 12.75 | 16.12 |
| NPS 14 | 21.00 | 18.75 | 12 | 1.12 | 14.000 | 14.00 | 17.75 |
| NPS 16 | 23.50 | 21.25 | 16 | 1.12 | 16.000 | 16.00 | 20.25 |
| NPS 18 | 25.00 | 22.75 | 16 | 1.25 | 18.000 | 18.00 | 21.62 |
| NPS 20 | 27.50 | 25.00 | 20 | 1.25 | 20.000 | 20.00 | 23.88 |
| NPS 24 | 32.00 | 29.50 | 20 | 1.38 | 24.000 | 24.00 | 28.25 |
Bolt holes in ASME B16.5 are 1/8 in larger than the bolt. Full-face gaskets use the flange OD, bolt holes and the B16.21 ID. Flat flange plates use the pipe OD (ASME B36.10) as the bore; add clearance for a slip-on fit.
EN 1092-1 PN16 flanges (mm)
| Size | D (OD) | K (bolt circle) | n bolts | L (hole) | Bolt | Pipe OD |
|---|---|---|---|---|---|---|
| DN15 | 95 | 65 | 4 | 14 | M12 | 21.3 |
| DN20 | 105 | 75 | 4 | 14 | M12 | 26.9 |
| DN25 | 115 | 85 | 4 | 14 | M12 | 33.7 |
| DN32 | 140 | 100 | 4 | 18 | M16 | 42.4 |
| DN40 | 150 | 110 | 4 | 18 | M16 | 48.3 |
| DN50 | 165 | 125 | 4 | 18 | M16 | 60.3 |
| DN65 | 185 | 145 | 8 | 18 | M16 | 76.1 |
| DN80 | 200 | 160 | 8 | 18 | M16 | 88.9 |
| DN100 | 220 | 180 | 8 | 18 | M16 | 114.3 |
| DN125 | 250 | 210 | 8 | 18 | M16 | 139.7 |
| DN150 | 285 | 240 | 8 | 22 | M20 | 168.3 |
| DN200 | 340 | 295 | 12 | 22 | M20 | 219.1 |
| DN250 | 405 | 355 | 12 | 26 | M24 | 273.0 |
| DN300 | 460 | 410 | 12 | 26 | M24 | 323.9 |
DN65 PN16 has 8 bolts in EN 1092-1; older DIN flanges had 4. Pipe OD is ISO series 1 (EN 10220). EN ring gaskets here are sized as K minus the bolt size, not taken from EN 1514-1.
Roller chain pitch and roller diameter
| Chain | Pitch | Roller dia | Standard |
|---|---|---|---|
| ANSI 25 (1/4") | 0.25 in | 0.13 in (bushing) | ANSI B29.1 |
| ANSI 35 (3/8") | 0.375 in | 0.2 in (bushing) | ANSI B29.1 |
| ANSI 40 (1/2") | 0.5 in | 0.312 in | ANSI B29.1 |
| ANSI 50 (5/8") | 0.625 in | 0.4 in | ANSI B29.1 |
| ANSI 60 (3/4") | 0.75 in | 0.469 in | ANSI B29.1 |
| ANSI 80 (1") | 1 in | 0.625 in | ANSI B29.1 |
| ISO 06B (9.525 mm) | 9.525 mm | 6.35 mm | ISO 606 |
| ISO 08B (12.7 mm) | 12.7 mm | 8.51 mm | ISO 606 |
| ISO 10B (15.875 mm) | 15.875 mm | 10.16 mm | ISO 606 |
| ISO 12B (19.05 mm) | 19.05 mm | 12.07 mm | ISO 606 |
| ISO 16B (25.4 mm) | 25.4 mm | 15.88 mm | ISO 606 |
Keyways: DIN 6885-1 (mm) and ANSI B17.1 square keys (in)
| Bore over / up to | Key b × h | Hub t2 |
|---|---|---|
| 6 / 8 | 2 × 2 | 1 |
| 8 / 10 | 3 × 3 | 1.4 |
| 10 / 12 | 4 × 4 | 1.8 |
| 12 / 17 | 5 × 5 | 2.3 |
| 17 / 22 | 6 × 6 | 2.8 |
| 22 / 30 | 8 × 7 | 3.3 |
| 30 / 38 | 10 × 8 | 3.3 |
| 38 / 44 | 12 × 8 | 3.3 |
| 44 / 50 | 14 × 9 | 3.8 |
| 50 / 58 | 16 × 10 | 4.3 |
| 58 / 65 | 18 × 11 | 4.4 |
| 65 / 75 | 20 × 12 | 4.9 |
| 75 / 85 | 22 × 14 | 5.4 |
| 85 / 95 | 25 × 14 | 5.4 |
| 95 / 110 | 28 × 16 | 6.4 |
| 110 / 130 | 32 × 18 | 7.4 |
| 130 / 150 | 36 × 20 | 8.4 |
| Bore over / up to | Square key |
|---|---|
| 5/16 / 7/16 | 3/32 |
| 7/16 / 9/16 | 1/8 |
| 9/16 / 7/8 | 3/16 |
| 7/8 / 1-1/4 | 1/4 |
| 1-1/4 / 1-3/8 | 5/16 |
| 1-3/8 / 1-3/4 | 3/8 |
| 1-3/4 / 2-1/4 | 1/2 |
| 2-1/4 / 2-3/4 | 5/8 |
| 2-3/4 / 3-1/4 | 3/4 |
| 3-1/4 / 3-3/4 | 7/8 |
| 3-3/4 / 4-1/2 | 1 |
| 4-1/2 / 5-1/2 | 1-1/4 |
| 5-1/2 / 6-1/2 | 1-1/2 |
Keyways are drawn at nominal size without tolerances. ANSI hub depth is half the key at the side wall of the keyway.
Tips for Cutting the Parts
- Need a shape that isn't here? Open the DXF in the DXF Sketcher to add cut-outs, tabs or extra holes, then export it again.
- Allow for kerf. The DXF is the finished size. Let your CAM apply kerf compensation: outside the outline, inside the holes. Typical kerf is 0.1 to 0.3 mm on a fibre laser, 1 to 2 mm on plasma and about 0.8 to 1 mm on a waterjet.
- Mind the smallest hole. Plasma holes under about 1 × thickness (1.5 × for clean bolt holes) come out tapered and rough. A laser manages about 0.5 to 1 × thickness. Cut undersize and drill or ream holes that must fit. The Fastener Clearance Calculator and Tap Drill Calculator give the sizes.
- Gears and sprockets. Thermal cutting rounds small teeth. Waterjet or laser suits module 1.5 and up, or #40 chain and up, in thin plate. Check a short length of chain on a test-cut sprocket before you cut a batch.
- Check the fit first. Print the SVG at 100 % and lay it over the mating flange, or cut one part in cheap material. Bolt circles can be checked with the Bolt Circle Calculator.
- Nest and weigh. Lay the parts out with the Sheet Cut Optimizer and work out their weight with the Weight Calculator. For shapes you only have on paper, try the Image to DXF Converter.
Frequently Asked Questions
The file is the widely supported R12 DXF format with polylines, circles and lines, so it opens in AutoCAD, Fusion 360, SolidWorks, LibreCAD, QCAD, Inkscape, SheetCam and most laser and plasma software. If your software does not like polylines with arcs, choose separate LINE and ARC entities.
Yes. The tooth is made by rolling a standard rack around the gear, the way a hob cuts it, so the flanks are true involutes and the root fillet is the curve the rack tip leaves. The flank is written as short lines that stay within 0.002 mm of the true curve. The tip and root are true arcs.
Below about 17 teeth at 20° a standard rack cuts away the bottom of the flank. That weakens the tooth and shortens contact. Add positive profile shift (the tool tells you how much), use a 25° pressure angle, or use more teeth. A shifted gear has a larger outside diameter, so the centre distance or mating gear must suit.
No. The drawing is the finished part. Set kerf compensation in your CAM or cutting software so it cuts outside the outline and inside the holes. Adding kerf to the drawing as well would make the part wrong by a full kerf.
They are taken from ASME B16.5 Class 150, ASME B16.21 and EN 1092-1 PN16, and the tables are shown on this page. Always check them against the standard and the flange you are matching. EN ring gaskets are sized to sit inside the bolts (K minus the bolt size), not taken from EN 1514-1.
OUTLINE holds the outer profile as one closed shape. HOLES holds holes, slots and bores. CENTER holds centre marks, bolt circles and the pitch circle. CENTER is left out unless you switch it on, so it cannot be cut by mistake.
Geometry follows the standards and formulas named on this page, but tables can have typos and your application may need different clearances. Check critical sizes and a test piece before cutting production parts.