FreeCAD Extension (Year 7 Robotics)

An extension to Workshop 1 Hardware and Networks's sibling, Workshop 2: Robotics & Smart Devices.

So you've finished your Sphero hat in TinkerCAD and you want to know what the "grown-up" 3D tools look like. This page is for you. It's optional. Your Workshop 2 booklet does not need any of this.

What FreeCAD adds on top of TinkerCAD

TinkerCAD is brilliant for getting a shape out of your head and onto the print bed fast. You drag blocks, you combine them, you export. Done.

FreeCAD is a different kind of tool. It's parametric, which means every part of your design remembers how it was made. If you decide the hole in your Sphero hat needs to be 74 mm across instead of 72 mm, you change one number and the whole model updates — holes, pockets, fillets and all. That's how real engineers design things they might have to tweak later. It is slower to learn, but it gives you precise control and a workflow that looks a lot like what people use in industry.

FreeCAD is free, open source, and runs on Windows, Mac, Linux and Raspberry Pi. There is no account to make and nothing to pay for.

Where to start

These are the resources I'd point a Year 7 student at first. They are all free, and none of them try to teach you everything in five minutes.

• FreeCAD Getting Started (official docs) — The official wiki's beginner page. Calm, written, step-by-step, and it matches whatever version you install.
• Download FreeCAD — Grab version 1.0 or newer. The installers are straightforward; ask an adult if you're on a school laptop.
• MangoJelly Solutions — FreeCAD for Beginners (YouTube) — Joko's channel is the one most people recommend first. Slow voice, clear screen, no flashy edits. Start with his "FreeCAD 1.0 Beginners" playlist.
• FreeCAD Part Design Tutorial (official) — A written walkthrough of the Part Design workbench. This is the workbench you'll use for almost anything you'd print.
• FreeCAD Forum — Help — When you get stuck, search here first. The community is patient with beginners as long as you describe what you tried.

If you only pick one, start with the official Getting Started page and keep MangoJelly open in another tab for when the written version doesn't click.

Worked example: a small Sphero hat in FreeCAD

Here's what the workflow looks like. Don't try to follow exact clicks from this — use it as a map, then follow the docs linked at each step.

1. New document, Part Design workbench. File → New, then switch the workbench dropdown to Part Design. (docs)
2. Sketch the circle. Create a new sketch on the XY plane. Draw a circle. Add a diameter constraint and type the number — say, 80 mm for a hat that sits over a 72 mm Sphero. (Sketcher docs)
3. Pad it into a disc. Close the sketch, then Pad it upwards by 10 mm. You now have a solid puck. (Pad docs)
4. Pocket out the underside. Make a new sketch on the bottom face, draw a 72 mm circle, and Pocket it up 8 mm. That's the hollow the Sphero sits in. (Pocket docs)
5. Fillet the top edge. Use Fillet on the top circle of the puck to round it off. Try a 3 mm radius first. (Fillet docs)
6. Export an STL for printing. Select the body in the tree, File → Export, and choose STL. That file goes straight into your slicer. (Export docs)

The payoff: if your hat is too tight, open the first sketch, change 72 to 73, and everything below updates automatically. You don't have to rebuild anything. That's the parametric trick.

Cross-link

This page extends the "Designing a Hat for Your Robot" task in Workshop 2. For the core task you only need TinkerCAD — see the Workshop 2 page (coming soon) once it's up on the wiki.

This is an extension page — not required for the Workshop 2 core task. TinkerCAD is fine for everything in the booklet. Last updated: April 2026.