Optical encoder disc Ø60, 30 slots, Ø5 bore — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/encoder-disc/  (CC BY 4.0)
Basis: Slotted disc for a transmissive IR slot sensor (TCST2103, 3.1 mm gap): Ø60 × 1.5, 30 slots on a 48 mm circle, Ø5 bore
Catalog version: 2026-10-20

Sizes: see table below
- The disc is Ø60 × 1.5 mm with a Ø5 bore for a Ø5 shaft.
- It has 30 radial slots, each 2 mm wide × 6 mm long, centred on a Ø48 circle (from r 21 to r 27), 12° apart: 30 pulses per revolution.
- At 1.5 mm thick it passes through the 3.1 mm gap of a TCST2103-type IR slot sensor.
- Rpm = pulses per second × 60 / 30.

feature  size
disc  Ø60 × 1.5
bore  Ø5
slots  30 × 2 wide × 6 radial
slot circle  Ø48
pitch  12°

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Wikipedia: Thermocouple — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Thermocouple
- Wikipedia: Hall effect sensor — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Hall_effect_sensor
- Wikipedia: Dial indicator — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Dial_indicator
- Analog Devices: DS18B20 datasheet — PDF — Manufacturer datasheet — https://www.analog.com/en/products/ds18b20.html
- Long Earth Society: Engine and rig 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/encoder-disc/index.json
API: https://xemstudio.com/api/geometry?object=encoder-disc