Adding Components
Stage 1D · Methodology — Populating your assembly with COTS parts and detail bodies
From Skeleton To Machine
A robot is mostly parts you didn't model
- COTS = Commercial Off-The-Shelf (you buy it)
- Motors, gearboxes, bearings, wheels, fasteners
- Detail parts = the custom plates you design
- This lesson: pull them in and place them
Frame the big picture. So far they've built tube structure and a skeleton. Now we hang real hardware on it. Stress that FRC CAD is 80% assembling vendor parts and 20% designing custom plates. Knowing where to GET parts is as important as modeling them.
Components Vs Bodies
Each real-world object is its own Component
- A Component can hold one or many Bodies
- Components get their own origin and joints
- Right-click root > New Component for each part
- Never model two parts in one body
This is the #1 thing beginners get wrong vs Onshape. In Fusion there is no separate Part Studio — everything lives in one design, organized by Components. One physical thing = one Component. Demo right-clicking the top node and choosing New Component, then renaming it immediately. A loose body floating at the root is a code smell.
Where Cots Parts Come From
Vendors publish CAD — download, don't model
- REV, WCP, AndyMark, TTB, MAXSwerve sites
- McMaster-Carr for screws, nuts, bearings
- Grab STEP (.step) or Fusion (.f3d) files
- Save real files to a shared team folder
Walk them to revrobotics.com product page > Documents/CAD tab. Show that McMaster has a 'Product Detail' CAD dropdown — pick 3-D STEP. Emphasize: modeling a NEO motor yourself is a waste of an afternoon; the vendor's file is exact. Set up a team Fusion project folder so everyone inserts the same canonical parts.
Insert Methods
- Upload .step/.f3d to your Project
- Insert > Insert Derive or drag in
- Best for parts you reuse a lot
- Lives in your cloud data panel
- Insert > Insert McMaster-Carr
- Browse catalog inside Fusion
- Pick part, choose STEP, Save
- Auto-drops into the assembly
Two real workflows. Left: upload vendor STEP to the Data Panel, then Insert into Design (this creates a referenced/derived component you can update later). Right: the built-in McMaster-Carr browser is gold for hardware — demo searching '10-32 socket head' and inserting a screw. Warn that the McMaster picker sometimes defaults to a non-STEP format; always switch the dropdown to 3-D STEP before download.
Insert A Motor
Download the Kraken/NEO STEP from vendor
- Insert > Upload to current project
- Insert it; it lands at the origin
- Rename Component to 'Kraken X60'
- Ground nothing yet — joints come next
Live demo: insert a motor. It will dump in at the world origin, often rotated wrong — that's fine, joints fix orientation. Rename it the instant it appears (double-click in tree) so the tree stays readable. Common mistake: students insert 6 identical bearings all named 'Component1' and lose track. Name as you go.
Place A Bearing
Most FRC shafts ride on 1/2in hex bearings
- Use a flanged ball bearing (e.g. R8, 1.125in OD)
- Insert it, then snap into the bore
- One Component per bearing instance
- Copy-paste for multiples, don't re-insert
Bearings are everywhere — every rotating shaft needs two. Show the standard 1/2in hex bore bearing used in WCP/TTB gearboxes. Teach Copy (Ctrl+C) / Paste to make a second instance rather than re-inserting — pasted copies share the same source so updating one can update all (use Paste New for an independent copy). Most common error: bearing OD doesn't match the hole; check the spec sheet.
Add Fasteners
FRC standard hardware: 10-32 and 1/4-20
- Insert McMaster-Carr > socket head cap screw
- Match length to your stack-up thickness
- Add the matching nut or use tapped holes
- Don't over-detail every single screw
10-32 is the FRC workhorse thread; 1/4-20 for higher-load joints. Demo the McMaster picker live. Reality check for beginners: you do NOT need to CAD every fastener for a design review — model the critical ones, and don't let screw-modeling eat your week. But correct screw LENGTH matters: measure your material stack so the screw actually reaches its threads.
ONE PHYSICAL PART IS ONE COMPONENT
Insert vendor CAD instead of modeling it, name every component as you add it, and let joints handle placement.
Organize The Tree
A clean tree saves you at 2am before ship
- Rename every component immediately
- Group sub-assemblies into their own Components
- Use Activate to edit inside a sub-assembly
- Toggle visibility to find what you need
Teach nesting: a gearbox is a Component that contains the motor, gears, and bearings as child Components. Double-click a component to Activate it (the rest dims) so you work in context. This mirrors Onshape sub-assemblies. Show the eyeball visibility toggles — hiding clutter is how you stay sane in a busy drivetrain.
Common Mistakes
Inserting wrong units (mm vs inch) parts
- Bodies floating loose at the root node
- Duplicate names: Component1, Component2...
- Re-inserting instead of copy-pasting
- Modeling hardware you could download
Run through the gotchas. Units: McMaster gives a choice — FRC is imperial, but many parts model fine either way; just verify size with Inspect > Measure after inserting. Loose root bodies break joints later. Wrap by reminding them next lesson is Joints, where all these inserted components finally get constrained to move correctly.
Your Task
- Insert one drive motor (NEO or Kraken)
- Add two 1/2in hex bearings
- Insert four 10-32 cap screws
- Name every component clearly
- Save the design to your project
- File > Share > Public Link
- Copy the generated link
- Paste it on AltHub to submit
Hands-on deliverable. They don't need joints yet — just clean insertion and naming. Walk the room checking for the #1 error: unnamed components and loose root bodies. For submission, Fusion's Share > Public Link generates a viewable web link (no download needed by reviewer) — have them paste it into the AltHub board for this lesson.
🧰 Add-ins for this step
Use the installed AltSkripts / FRC-COTS tools here — don't do it the slow way.
- FRC-COTS — insert motors, bearings, and hardware as you populate the assembly.
You Can Now Populate An Assembly With Real Parts
- One physical part = one named Component
- Insert vendor CAD; don't re-model it
- Next up: Joints to make it all move
Your Task
- Model what this lesson covers in Fusion 360.
- Use the AltSkripts tools where they apply.
- Save it with a clear name.
- In Fusion: Share → Public Link → Copy.
- Paste the link below.
- A coach reviews it in AltHub.