ZJUN3D

What is ZJUN3D?

ZJUN3D is a free browser tool that turns a form of gear and mechanism settings into printable parts. It comes from ZJUN_3D, the maker behind the popular Ultimate Gear Parametric Generator on MakerWorld. In September 2026 it listed 29 generators, and 28 of them were gears and drive mechanisms: single spur, helical, herringbone, ring, rack, bevel, crown and worm gears, matched pairs, planetary sets, multi-stage reducers, a Geneva drive, a cam and follower, a ratchet and pawl, a GT2 timing belt drive and a universal joint. One extra generator builds cylinder bins for IKEA SKADIS and round-hole pegboards.

You choose a gear type or layout, then set values such as module, tooth count, pressure angle, backlash and bore shape with sliders and number fields. The server builds the model and shows a 3D preview, and the viewer can check the part against common printer beds, color overhangs and show dimensions. An optional AI assistant can turn a plain request into parameter changes. The gear tools export STL, 3MF and STEP, so you can keep editing in CAD if you want.

The site opens in Chinese, with an EN switch in the header, and was labeled a public test as of September 2026. Previews are free without an account, but downloads need a free account and use credits from signup and a daily check-in. It suits makers building gearboxes, robots or teaching models who want matching parts without doing the gear math.

What you can make

• Spur, helical and herringbone gears
• Worm drives and rack and pinion sets
• Planetary gear sets and reducers
• Geneva drives, cams and ratchets
• Universal joints and couplings
• Pegboard cylinder bins

How to use ZJUN3D

1. Open the generator list and pick a gear or mechanism
2. Switch the interface to English with the EN button if needed
3. Choose the gear type and set module, teeth, backlash and bore
4. Click Generate Preview and check the model in the 3D viewer
5. Log in and export STL, 3MF or STEP