3D Printed Roman Catapult (Working Onager Siege Engine)

Wreak historical havoc with this working Roman catapult — a miniature Onager, named after the wild donkey for how violently it kicks when fired.

Designed for real torsion-powered launches, this siege engine adds a touch of ancient chaos to any wargame, display shelf, or desk-based skirmish.

• Torsion-powered just like the Romans did it — using twisted cord for authentic launches.
• FDM-optimised design - tough, tested, and surprisingly powerful.
• Some assembly required - PDF instructions and video guide included.

💥 Follow VogMan for more printable siege weapons, terrain, and miniature madness! 

🎥 YouTube: @VogMan

🎉Premier Version with enhanced aesthetics and abilities here: cults3d

MATERIALS
It's all in the Instructions PDF, but nothing major… PLA, a little TPU, a few M3 bolts, sleeving, strong thread, and the spring from an ordinary click-top-pen... stuff many of us have lying around.

SAFETY
Seriously, don’t fire this at anyone. It packs a punch. Hurting people, even that annoying neighbour, isn’t what this build is about. Play responsibly!
Always supervise children and pets when using the Onager, and keep fingers clear of fast-moving or pinching parts. Also, be mindful of the choking hazard associated with small parts around pets and young children. 

This model is provided “as-is” without any warranty or guarantee of fitness for purpose. By downloading or printing this file, you assume all risk. The creator (VogMan) accepts no liability for injury, damage, or misuse. Models should be assembled and used with care and under supervision where applicable. Not suitable for children.

REQUESTS
Got a request for a model you'd like to see made?
I can’t promise I’ll get to everything, but I’m always happy to hear from folks. Just follow me and drop me a message.

LEGALITIES & USE
© VogMan, May 2025. Please respect my copyright and authorship.

These files are strictly for Personal Use Only.

You may:
✔ Print physical copies for yourself
✔ Share images of your prints online (credit to VogMan is appreciated)

You may NOT:
❌ Sell printed versions (unless licensed)
❌ Modify, share, or redistribute the digital files
❌ Use these files commercially without a license

Personal Use means just for you!

COMMERCIAL LICENSES
If you're a Registered VogMan Patron Commercial License holder, you're permitted to print and sell this item in line with that license.

However:
– The digital files remain the property of VogMan
– You may not share, modify, or distribute the digital files under any license

In short: the STLs are mine — printing is yours, with permission.

For full details about commercial licensing, click here:
https://www.vegoilguy.co.uk/commercial-license-info.php

FIND ME ONLINE
https://www.patreon.com/vegoilguy
https://www.youtube.com/@vogman
https://linktr.ee/vogman
https://www.instagram.com/the_vogman
https://www.facebook.com/thevogman
https://www.etsy.com/shop/VegOilGuy
http://www.vogman.co.uk

CONTACT
Have questions, feedback, or ideas? Reach out here:
https://www.vegoilguy.co.uk/contact_general.php