# Atomic Filament 3.5 kg spool

> What are the dimensions of the Atomic Filament 3.5 kg spool?

- Category: 3D printers & filament › Filament spools
- Kind: Modern device
- Basis: Manufacturer specifications (Atomic Filament)
- Page: https://xemstudio.com/objects/atomic-filament-3-5-kg-spool/ · JSON: https://xemstudio.com/api/geometry?object=atomic-filament-3-5-kg-spool · Plain text: https://xemstudio.com/objects/atomic-filament-3-5-kg-spool/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 304.8 | 304.8 | 95.25 |

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

## Notes

- The Atomic Filament 3.5 kg spool measures 304.8 mm across the flanges, 95.25 mm wide, with a 50.8 mm hub hole, as published by Atomic Filament.
- Atomic lists this spool as 12 × 3.75 in with a 2 in hole without labelling which figure is which; following its 1 kg wording (diameter × thickness), 12 in is taken as the diameter.
- The file is a solid envelope cylinder at the outer diameter and width with the hub hole through it; flange thickness, core diameter, ribs and windows are not modelled.
- True size, no printing tolerance added. Only published numbers are used; anything not published is said so.

## Sizes

| dimension | value |
|---|---|
| Outer (flange) diameter | 304.8 mm (12 in) |
| Width | 95.25 mm (3.75 in) |
| Hub hole diameter | 50.8 mm (2 in) |
| Published size | 12 in × 3.75 in × 2 in hole |
| Empty spool weight | 936 g |
| Filament capacity | 3.5 kg |

## Where the files are

- Atomic Filament: [FAQ - Atomic Filament](https://atomicfilament.com/pages/atomic-filament-faq) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/atomic-filament-3-5-kg-spool/index.json

- atomic-filament-3-5-kg-spool-spool: [STEP](https://xemstudio.com/files/hardware/atomic-filament-3-5-kg-spool/atomic-filament-3-5-kg-spool-spool.step) · [STL](https://xemstudio.com/files/hardware/atomic-filament-3-5-kg-spool/atomic-filament-3-5-kg-spool-spool.stl) — Spool envelope Ø304.8 × 95.25 mm with a Ø50.8 mm hub hole (flanges and core not modelled)

## Questions

**What size is the Atomic Filament 3.5 kg spool?**

304.8 mm outer diameter, 95.25 mm wide, 50.8 mm hub hole (12 × 3.75 in, 2 in hole).

**Does the Atomic Filament 3.5 kg spool fit a Bambu Lab AMS?**

Bambu Lab lists the AMS HT for spools 197–202 mm in diameter and 50–68 mm wide; at 304.8 × 95.25 mm this spool is outside that range on paper, so plan on an adapter or an external holder.

## Fits with

- [Filamentive 300–500 g cardboard spool](https://xemstudio.com/objects/filamentive-300-500-g-cardboard-spool/)
- [Filamentive 750 g cardboard spool](https://xemstudio.com/objects/filamentive-750-g-cardboard-spool/)
- [Filamentive 1 kg cardboard spool (narrow, from April 2025)](https://xemstudio.com/objects/filamentive-1-kg-cardboard-spool/)
- [Filamentive ReFill coil (for Bambu Lab reusable spool)](https://xemstudio.com/objects/filamentive-refill-coil/)