Study guide — what to focus on

This module is curated — the teaching is a top free course (linked in the card above); our job is to point you at the right things, make you prove it, and certify you. You've already got single-part modeling down (that's the prerequisite); this is the jump to multi-part assemblies.

The plan

1. Watch the course (the card above). You don't need to memorise it — aim to understand the ideas below.
2. Focus on these — they're what the check tests and what you'll use for real:
   • Components vs. bodies — make components first when you plan to assemble; a body is just geometry inside a component.
   • The joint origin — the snap point on each part that decides how they align and where motion pivots. Get this right and joints just work.
   • Joint types — rigid (locked, 0 degrees of freedom), revolute (rotates, like a hinge), slider (translates, like a drawer), plus cylindrical, pin-slot, planar, and ball.
   • As-built joints — relate parts that are already in their final position without moving them.
   • Joint limits & motion — cap a hinge at 110°, then drive it to watch it move.
   • Design intent — dimension to references and drive with parameters so a later edit updates the model the way you meant, instead of breaking it.
   • Interference & fit — check whether parts overlap, and leave a small clearance (tolerance) so mating parts actually assemble.
3. Prove it in Forge (next section) — apply assembly + design-intent thinking to a real two-part case.
4. Take the K-Check to earn your certificate.

Why this connects to building real products

A single part is easy; a product is parts that have to fit and move together. Everything above — components, joints, tolerances, design intent — is what makes a lid close, a button reach its switch, and two halves of a case snap shut. In Forge Prototype, when you describe a multi-part enclosure, the 3D part designer makes exactly these decisions: where the two halves mate, how much clearance to leave, where the opening for a button goes. Knowing the assembly vocabulary lets you read why it split and toleranced the design the way it did — and judge whether it will actually go together on the bench.

Time to apply it. The course taught you how parts become an assembly — components that mate, joints that constrain, and the small tolerances that let them actually fit. Now use that lens on a real case.

Send the prompt below in the Forge 3D part designer and watch it split the enclosure into a base and a lid, mate the two halves, and cut a side opening for the button — leaving clearance where the parts meet.

As you read the result, connect it back to the course: where are the two parts toleranced so they snap together instead of jamming? Which surfaces are the mating (joint) faces? That mapping — assembly thinking ↔ a real printable part — is the whole point.