Sprocket STEP, DXF & SVG Generator

Generate a roller chain sprocket in the browser and download it as a STEP solid, DXF, or SVG, or send it directly into a Fabworks quote.

Build a laser-cut plate sprocket

Select a roller chain and tooth count, then set the bore, holes, and plate.

Units
rpm
in
in

Add the driven sprocket to see the ratio and output speed, and generate both parts.

Hub, holes, and plate

in
Min. feature 0.050 in · 1.27 mm

Generated dimensions

Recommended chain fit
Pitch diameter
2.8794 in
Outside diameter
3.1356 in
Root diameter
2.5628 in
Roller seat radius
0.1583 in
Chain speed At 300 rpm
225 ft/min
Plate
Steel 1008 · 0.187 in
Chain side clearance
0.0628 in per side

ANSI roller chain dimensions

Recommended plate thickness leaves side clearance inside the chain.

ANSI #40 selected
ChainPitchRoller diameterInside widthIdeal plate
ANSI #250.250 in · 6.35 mm 0.130 in · 3.302 mm 0.125 in · 3.175 mm 0.098 in · 2.5 mm
ANSI #350.375 in · 9.525 mm 0.200 in · 5.08 mm 0.188 in · 4.763 mm 0.118 in · 3 mm
ANSI #400.500 in · 12.7 mm 0.312 in · 7.925 mm 0.313 in · 7.938 mm 0.250 in · 6.35 mm
ANSI #410.500 in · 12.7 mm 0.306 in · 7.772 mm 0.250 in · 6.35 mm 0.188 in · 4.763 mm
ANSI #500.625 in · 15.875 mm 0.400 in · 10.16 mm 0.375 in · 9.525 mm 0.313 in · 7.938 mm
ANSI #600.750 in · 19.05 mm 0.469 in · 11.913 mm 0.500 in · 12.7 mm 0.375 in · 9.525 mm

Laser-cut profile preview

The B29.1 profile uses a roller seating curve, working curve, tangent flat, and topping curve. The dashed circle is the pitch circle and the filled circle is a seated roller.

ASME B29.1 profile

Download the manufacturing files

100% in-browser

STEP solids are built and checked in your browser. DXF and SVG drawings use lines and true arcs at full scale. Nothing is uploaded until you order.

  • Sprocket

    3.136 in × 3.096 in

Laser cut it at Fabworks

We generate the STEP files, add them to a new quote, and open it in a new tab where you can review material, finish, and quantity.

The STEP uses the ASME B29.1 theoretical tooth form and catalog outside-diameter truncation. Manufacturing tolerances, material, heat treatment, alignment, lubrication, and application loads still require engineering review.

How it works

Enter the chain and tooth count, add a bore and holes, and the page builds the sprocket in your browser as a STEP solid, a DXF in millimeters, or an SVG. The STEP can go straight into a Fabworks quote. Check the plate thickness against the chain first: a plate thicker than the tooth width will not clear the chain’s inner plates.

How to use the calculator

  1. 1Set the chain, tooth count, and tooth fit until the preview matches your drive.
  2. 2Add the bore and the hole patterns your hub or shaft needs.
  3. 3Pick the material and a thickness at or under the tooth width, then clear any narrow-gap, tip-land, or web warnings.
  4. 4Download the STEP, DXF, or SVG for your own CAD, or use Order to open a quote with the STEP attached.

Laser-cut #40 sprocket STEP

Inputs
An 18-tooth #40 roller chain sprocket with a 0.500 in bore and an available steel plate thickness.
Result
One closed, uniform-thickness STEP solid with a 2.879 in pitch diameter and 3.136 in outside diameter, reopened for validation.

The generated file uses the same tooth profile, bore, and thickness shown in the preview and dimension results.

What to know before using the result

Does file generation happen in the browser?
Yes. The page builds the STEP solid and reopens it to check it, all locally, so no CAD software is required.
What is in the DXF file?
A closed 2D outline in millimeters made of lines and arcs, including the bore and holes. Tooth curves stay within 0.005 mm of the true profile, so laser, waterjet, and CNC software read it cleanly.
Can I add a hub or spokes in my own CAD?
Yes. Import the STEP as a solid or the DXF as a sketch, add what the generator does not draw, then upload the edited file to a Fabworks quote.
What happens when I click Order?
A new quote opens in another tab with the generated STEP attached, and it goes through our normal material, manufacturability, and pricing review.
Will the chain fit a laser-cut sprocket?
Our standard laser tolerance is ±0.005 in, and most parts come out near ±0.002 in. The edge tapers about 0.001 in per 0.1 in of thickness. Test-fit the chain on one part before ordering a quantity, and use the free-running fit if it binds.

Formula

Dₚ = p ÷ sin(180° ÷ N)

Pitch diameter is the chain pitch divided by sin(180° ÷ teeth). The teeth follow the ASME B29.1 construction: a roller seating curve, a working curve, a short straight, and a topping curve, trimmed at the catalog outside diameter.

Engineering references

Assumptions and limits

  • Chain sizes use nominal ASME B29.1 pitch and roller diameter. Free-running fit and tip relief depart from the standard tooth form on purpose.
  • The STEP is a flat plate of one thickness with the bore and holes you set. It has no hub or set screw.
  • The plate is as hard as the sheet it is cut from. Chain makers recommend hardened teeth on sprockets of 25 teeth or fewer.
  • Chain speed assumes the sprocket turns at the entered shaft speed with no slip.

Keep designing

Order Sheet Metal Parts

Upload a 2D DXF or 3D STEP file for an instant laser cutting quote. Quote in seconds, order in minutes, receive parts in days.

STEP / DXF up to 24MB

Your files are safe, secure, and retain all intellectual rights.