# X8 coaxial quad

> What is an X8 coaxial drone?

- Category: Drone design › Drone frame layouts
- Kind: Standard part
- Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
- Page: https://xemstudio.com/objects/x8-coaxial/ · JSON: https://xemstudio.com/api/geometry?object=x8-coaxial · Plain text: https://xemstudio.com/objects/x8-coaxial/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files Xem Studio Design License (free to use and sell from, not to redistribute as files: https://xemstudio.com/license/)
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no printing tolerance added.

## Notes

- X8 puts a coaxial pair on each arm of an X: more lift and redundancy in a compact, foldable footprint, at a coaxial efficiency penalty of ~10-20% (Oscar Liang).
- The file is a reference example built by Xem Studio from the numbers above (Illustrative; true X with coaxial pairs.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

## Sizes

| parameter | value or range | source |
|---|---|---|
| Coaxial efficiency loss | ~10-20% | Oscar Liang |

## Where the files are

- Oscar Liang: [Types of multicopter](https://oscarliang.com/types-of-multicopter) — web — Publisher's page; dimensions are facts
- r/multicopter wiki (mirror): [Anatomy of a Multicopter](https://r.datuan.dev/r/multicopter/wiki/anatomy) — web — Publisher's page; dimensions are facts
- ArduPilot: [Archived: Advanced MultiCopter Design](https://ardupilot.org/copter/docs/advanced-multicopter-design.html) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/x8-coaxial/index.json · license: https://xemstudio.com/files/hardware/x8-coaxial/LICENSE.md

- x8-coaxial-layout: [STEP](https://xemstudio.com/files/hardware/x8-coaxial/x8-coaxial-layout.step) · [STL](https://xemstudio.com/files/hardware/x8-coaxial/x8-coaxial-layout.stl) — true x frame layout: 550 mm motor-to-motor diagonal, 12 in props (discs show the swept area; arms and plate illustrative)

## Questions

**X8 vs flat octo?**

Same motor count, smaller footprint, lower efficiency (Oscar Liang).

## Fits with

- [True X quad frame](https://xemstudio.com/objects/true-x-frame/)
- [Stretched X frame](https://xemstudio.com/objects/stretched-x-frame/)
- [Squashed (wide) X frame](https://xemstudio.com/objects/squashed-x-frame/)
- [Hybrid X frame](https://xemstudio.com/objects/hybrid-x-frame/)
- [Deadcat frame](https://xemstudio.com/objects/deadcat-frame/)
- [H frame](https://xemstudio.com/objects/h-frame/)