PartScope

PartScope is a small Three.js viewer for reviewing mechanical assemblies in the browser.

Why

Most CAD review tools are either too heavy, too closed, or too tied to a larger system. PartScope keeps the job narrow:

• inspect a mechanical assembly quickly
• compare parts in context
• check sections, edges, and exploded views
• export common CAD/CAM handoff formats
• keep the asset flow local and simple

Features

• View presets for fast orientation
• Exploded view and adjustable spin
• Section cuts on X, Y, and Z
• Edge, wireframe, x-ray, and grid overlays
• Part selection, focus, and isolation
• Movable and collapsible inspector palette
• Fullscreen mode
• CAD import for STL, OBJ, PLY, GLB, GLTF, and 3MF
• CAD export for STL, OBJ, PLY, and GLB
• CNC contour G-code export
• Additive print package export with layer SVGs, contour JSON, source STL, manifest, README, and animated preview GIF
• Bundled demo assemblies
• Local CAD upload from file picker or drag and drop

Quick Start

npm install
npm run dev

That starts the viewer with bundled demo assemblies, including the Sensor Puck in public/models/sensor_puck. Use the load control or drag supported CAD files onto the window to inspect local geometry without uploading it anywhere.

Bundled demos:

• Sensor Puck: multi-part STL assembly
• Boosted Remote: GLB scene model

Model Contract

The bundled Sensor Puck demo assembly is loaded from:

• sensor_puck_base.stl
• sensor_puck_battery_18650.stl
• sensor_puck_main_board.stl
• sensor_puck_mezz_connectors.stl
• sensor_puck_mic_capsules.stl
• sensor_puck_sensor_board.stl
• sensor_puck_top.stl
• sensor_puck_vibration_sensor.stl

Build

npm run build

Embedding

PartScope can be consumed as a package by host apps that serve the built viewer as static assets.

npm run build:embed
partscope-copy-assets public/tools/partscope

Then render the packaged iframe component from the host app:

import { PartScopeEmbed } from "partscope";

export function PartScopeDemo() {
  return <PartScopeEmbed className="h-full w-full" />;
}

Notes

• The viewer stays separate from hardware generation scripts so the review surface can evolve independently.
• Local uploads are parsed in the browser and are not sent to a server.