Neodymium block magnets: 30 × 10 × 4 mm — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/neodymium-block-magnets/  (CC BY 4.0)
Basis: Nominal size as sold; magnetised through the 4 mm dimension
Catalog version: 2026-10-20

Sizes: see table below
- A rectangular neodymium block 30 × 10 × 4 mm, magnetised through its 4 mm thickness, a stock size. Drawn at the nominal size with square edges.
- On the free-piston mover 48 of them sit on the 12 flats of the core in four rows, alternately N and S outward.

length_mm  width_mm  thickness_mm  magnetised
30  10  4  through 4

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Xem Studio: tools/gen_ta_power.py: the network model and every dimension on this page — code — CC BY 4.0 — https://xemstudio.com/
- Long Earth Society: Engine builds — web, video — LES site — https://longearthsociety.com/engineering/

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/neodymium-block-magnets/index.json
API: https://xemstudio.com/api/geometry?object=neodymium-block-magnets