generateSTL
ENDE
Open the builder

Mechanical parts, generated.

Gears, screws, boxes and bearings as watertight STL files. Set the parameters, watch the mesh build live, print.

Generate your first STL →Browse the generators

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A workshop, not a form

Change dimensions in the 3D viewer, then export the model as STL. The browser preview helps you inspect the shape; the export service builds the printable mesh from your parameters. Check the downloaded file in your slicer and calibrate moving fits on your printer.

The screw builder with thread parameters and a live rendered M6 set of screw, nut and washer in the 3D viewer
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STL

export for your slicer

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open source engine

8

gear types, true involutes

Built like the parts it makes

Herringbone gear rendered live in the 3D viewer

True involute geometry, live

Real tooth math, not decorative wedges. Flanks are sampled along the involute. Matching gears also need compatible dimensions, alignment and suitable print clearance.

Parameter panel with module, teeth and pressure angle

Every parameter exposed

Module, teeth, pressure angle, profile shift, helix, bores. Sliders for speed, fields for precision.

ModuleTeethPressure angleProfile shiftHelix angleBore

STL header

GSTL SPGM2.000Z24AP20.5H10.000

Parameters live inside the file

Each STL header records its own recipe. Drop a months-old file back in and keep working where you stopped.

Manufacturablem 2.00z 24ø 52.0 mm

Manufacturability checks

The status bar flags fragile teeth and impossible bores before the slicer ever sees them.

Hex
Square
Round
Keyway

Bores that grip

Hex, square, circular and keyway bores generated in place. Choose the shape and size for your shaft, then check the printed fit.

From dimensions to an STL file

Pick a part

Spur, helical, herringbone, bevel pair, rack, screw, box or bearing. Templates start you at sane defaults.

Tune it live

Drag the sliders, watch the mesh rebuild in real time. Use the preview to inspect the shape, then inspect the exported mesh in your slicer.

Download and print

One click exports a watertight binary STL with your parameters stored in the header. Slice it anywhere.

The generators

Six parametric tools for mechanical parts. Use compatible module and pressure angle when pairing spur gears, and review the additional requirements for each gear type.

A group of generated gears: a meshing spur pair, a herringbone gear and a bevel gear

Gear Generator

Spur, helical, herringbone, internal, rack and bevel gears with true involute profiles.

Open
A metric hex head bolt with a matching hex nut and a flat washer

Screw Generator

Metric screws, nuts and washers with printable threads.

Open
An open parametric storage box with thin walls and its lid floating above it

Box Generator

Parametric storage boxes with optional lids and adjustable clearance.

Open
A deep groove ball bearing with three concentric rings, printed in place as one part

Bearing Generator

Print-in-place sliding bearings in standard and custom sizes.

Open
A round ventilation grille with a hexagonal perforation pattern inside a solid frame ring

Grille Generator

Ventilation grilles and covers in custom patterns.

Open
A pegboard panel with a grid of threaded holes and two matching pegboard screws

Pegboard Generator

Pegboards and hooks for wall organization.

Open

By part type

Two meshing brass spur gears, a 30 tooth wheel driving a 15 tooth pinion at module 2Spur Gear GeneratorA meshing helical gear pair with slanted teeth, 28 and 16 teeth at a 22 degree helix angleHelical Gear GeneratorA brass herringbone gear whose double helix teeth meet in a sharp V around the rimHerringbone Gear GeneratorAn internal ring gear with 44 teeth cut on the inside and a brass pinion running against themInternal Gear GeneratorA straight bevel gear pair for a 90 degree drive, a 24 tooth crown wheel with a 12 tooth pinionBevel Gear GeneratorA gear rack with straight teeth and a brass pinion meshed on top, turning rotation into linear motionRack and Pinion GeneratorActual STL contour drawing: 24-tooth sun, three 24-tooth planets at 120 degrees and a 72-tooth ringPlanetary Gear GeneratorClose-up of a metric threaded rod showing the ISO thread crests and the pitchThread GeneratorA hex head bolt with its nut threaded halfway down the shankNut and Bolt GeneratorA closed storage box with the lid seated on the body and a crisp parting line3D Printable Box GeneratorTwo nesting storage boxes in different sizes with their lids leaning against themBox GeneratorA deep groove ball bearing seen edge on, showing the outer race and the seam between the ringsBearing GeneratorTwo meshing brass spur gears, a 30 tooth wheel driving a 15 tooth pinion at module 23D Print Tolerance Test GeneratorA single 30 tooth brass spur gear seen face on, ready to import into CAD as a solid bodyGear Generator for SolidWorksA helical gear pair in steel and brass seen from a steep angle, teeth fully engagedGear Generator for Fusion 360A three stage gear train: a brass wheel, a steel idler pinion and a second brass gearGear Generator for OnshapeA herringbone gear machined from dark steel, seen from above so the chevron teeth readGear Generator for OpenSCAD

Calculate the dimensions before building the gear

Find module, pitch diameter and center distance, or compare the speeds in a planetary gear set. Each calculator includes its formula, a worked example and the limits of the result.

Gear module and diametral pitch calculator

Calculate gear module from pitch diameter and teeth, convert diametral pitch, and check standard spur-gear dimensions with a worked example.

Spur gear center distance calculator

Calculate center distance for a standard spur-gear pair from module and tooth counts. See the formula, units and limits before setting shaft positions.

Planetary gear ratio calculator

Calculate planetary gear ratios from tooth counts and fixed, input and output members. See rotation direction, assumptions and a worked example.

All gear calculatorsPlanetary gears: parts and three operating modes

From the workshop

All guides

Gear Module Explained

Understand gear module, pitch diameter and diametral pitch.

Open

3D Printed Gears: Materials, Fit and a Test Log

Choose materials and settings for 3D printed gears.

Open

Build the dimensions your next part needs.

Open the gear generator →

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