# Flat-bottom hull

> What is a flat-bottom hull good for?

- Category: Boat design › Hull types
- Kind: Standard part
- Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
- Page: https://xemstudio.com/objects/flat-bottom-hull/ · JSON: https://xemstudio.com/api/geometry?object=flat-bottom-hull · Plain text: https://xemstudio.com/objects/flat-bottom-hull/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

- A flat-bottom hull is very stable, has low draft, planes easily with little power and is cheap to build, but gives the bumpiest, wettest ride in waves (BoatTest).
- The bow may still have steep deadrise; transoms below 17 deg are described as flatter at the stern (BoatTest).
- Used on: Jon boats, Skiffs.
- The file is a reference example built by Xem Studio from the numbers above (Reference RC mono: 585 mm length and 20 deg transom deadrise (SV Design Stealthwake data); 181 mm is an unlabelled width in the same source's deadrise diagram.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

## Sizes

| parameter | value or range | source |
|---|---|---|
| Transom deadrise | near 0 deg (below 17 deg = 'flatter') | BoatTest |

## Where the files are

- BoatTest: [To Deep-V or Not to Deep-V](https://boattest.com/view-news/6472_To-Deep-V-or-Not-to-Deep-V) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/flat-bottom-hull/index.json · license: https://xemstudio.com/files/hardware/flat-bottom-hull/LICENSE.md

- flat-bottom-hull-hull: [STEP](https://xemstudio.com/files/hardware/flat-bottom-hull/flat-bottom-hull-hull.step) · [STL](https://xemstudio.com/files/hardware/flat-bottom-hull/flat-bottom-hull-hull.stl) — flat hull, 585 × 181 mm, deadrise 0° (sections illustrative, scale to your boat)

## Questions

**Why so bumpy?**

With no V the bottom slams flat onto waves (BoatTest).

## Fits with

- [Deep-V hull](https://xemstudio.com/objects/deep-v-hull/)
- [Modified-V (semi-V) hull](https://xemstudio.com/objects/modified-v-hull/)
- [Cathedral (tri-hull)](https://xemstudio.com/objects/cathedral-tri-hull/)
- [Tunnel hull (tunnel catamaran)](https://xemstudio.com/objects/tunnel-hull-catamaran/)
- [Three-point hydroplane](https://xemstudio.com/objects/three-point-hydroplane/)
- [Stepped hull](https://xemstudio.com/objects/stepped-hull/)