Macroelectronics | Go Education Project

Information

Mon, 01 Jan 0001 00:00:00 +0000

Visit the to download the example code and get the latest version.

Electronics, but way too big.

This repo is home to fully functional, 15×-scale, 3D-printed replicas of the components you’d find in . Every replica is a real, working circuit, there’s an actual microcontroller, component or sensor hiding inside each one, wired out to giant, kid-friendly terminals you can poke, clip onto, and solder to without a magnifying glass.

Why though

Because the coolest chips on the planet are also small enough to lose in a carpet. A real is about the size of your thumbnail, great for finished projects, terrible for the first time you try to explain “this is GPIO pin D7” to someone whose hands (or curiosity) haven’t grown into tiny header pins yet.

So: blow it up 15×. Keep it 100% real and functional. Let people press giant buttons, plug in a giant-but-real USB-C cable, and watch a giant strip of LEDs light up because of code they wrote. That’s the whole idea: a teaching prop, a conversation starter, and a genuinely usable dev board, all at once.

This is built for workshops and hacksessions, but the designs are open, feel free to print your own.

What’s in the kit (so far)

Replica	Based on	Status
	The from the starter kit	Fully built, see the
	The Grove rotary angle sensor from the starter kit	Fully built, see the
	Not actually in the official kit, we just wanted a giant LED	3D model ready

More macro-sized components will show up here as they get printed, wired, and (usually) accidentally left running on someone’s desk.

Does it actually works?

Yes! The idea is to get fully functional 15× hardware. In the case of the XIAO a real XIAO is hidden inside the 3D-printed housing and every pin it has is routed out to a giant copper-tape pad at 15× scale, in the exact same layout as the real board’s silkscreen. Both buttons works too. You interact with the giant version exactly like you would the tiny one: press its buttons, plug in its (real, tiny) USB-C cable, wire up giant jumper cables to giant pads and the real chip underneath does the work.

No emulation, no fake props. If you can flash a real XIAO ESP32-C3, you can flash this one, it just happens to take up half your desk.

Curious how the giant XIAO was actually built (copper tape wiring, swappable chip housing, the works)? Read the .

Repo layout

.
├── assets/ Logos, stickers, and images used across the docs
├── hardware/ 3D printable parts (STL / 3MF / DXF) for each replica,
│ one folder per component
├── examples/ TinyGo firmware you can flash onto the real chip
│ hidden inside each replica
├── go.mod
└── go.sum

Getting started

You’ll need installed, and the real board that lives inside the replica you’re building (currently a ).

Clone this repo, pick an example, and flash it like any other TinyGo project:

git clone ssh://git@git.madriguera.me/GoEducation/macroelectronics.git
cd macroelectronics
tinygo flash -target=xiao-esp32c3 ./examples/<example-name>

Then head to hardware/<component> for the 3D files and, where available, a build guide.

Open hardware

Everything here, 3D models, wiring notes, and firmware, is free to print, wire up, remix, and use in your own workshops. If you build your own giant component, we’d love to hear about it.

XIAO

Mon, 01 Jan 0001 00:00:00 +0000

Visit the to download the example code and get the latest version.

What if your development board just wasn’t big enough? This is a fully functional, 15× scale replica of the — 3D printed, wired up, and ready to actually run .

Yes, it’s a giant board built to run code meant for a board the size of your thumbnail. The irony is intentional.

The original vs the replica. The real XIAO weighs about 5 grams and fits on a fingernail. Its giant twin takes up half a desk.

The concept

The is one of the smallest and most capable microcontroller boards available — roughly 21 × 17.5 mm, with a USB-C port, WiFi/BLE, and a full set of GPIO pins. It’s one of the go-to boards for , the Go compiler that targets microcontrollers.

The goal was to build something that works as a conversation starter, a teaching prop, and a practical tool all at once.

The result is a giant XIAO that:

Is electrically functional — all pins are wired through to a real XIAO hidden inside
Has a swappable chip housing (the top gray block, held by screws) to adapt the form factor for different tasks
Has a swappable interior (held by magnets) so the inside can be reconfigured — for example, as a compact component organizer for workshop sessions
Has a giant USB-C port that actually accepts a real USB-C cable to power and program the hidden XIAO

Part 1: The 3D printed parts

The board is split into several distinct printed pieces to fit most common 3D printer beds (20×20 cm). It has slots for joints, and the screws from the chip housing (the big gray box) help hold everything together.

Two button frames, and the round caps for the BOOT and RESET buttons.

The main board frame is printed in black and assembled in sections. The chip housing on top and the USB-C connector shell are printed in gray to match the original XIAO’s color scheme. The buttons — BOOT and RESET — are separate two-part pieces: a square frame and a round cap, just like the originals.

Everything is printed without supports where possible to keep the surfaces clean. The tolerances are tight enough that the buttons feel satisfying to press.

Part 2: Wiring the pins — copper tape as a conductor

Here’s the key technical trick: the 14 GPIO pads (plus GND, 3V3, VUSB, BAT, and the debug pads) are reproduced as conductive copper tape patches wrapped around 3D printed pin stubs on the edges of the board.

Wiring and applying copper tape. Each pad becomes its own solderable contact.

Each stub has copper tape folded over and pressed into the cavity, creating a continuous conductive surface. A wire is then soldered to each pad and routed through the board’s internal channels to the real XIAO.

Every pin gets its own copper-tape pad and soldered wire. There are 14 GPIO pins plus power, ground, and the debug pads — 22 connections in total.

The back face of the board reproduces the original XIAO labels — D0 through D9, BAT+/−, 3V3, VUSB, GND, and the JTAG debug pads — all silk-screened as part of the 3D print itself. The battery pads and JTAG pads are printed for looks but intentionally left non-functional for safety.

An exact reproduction of the XIAO pinout, at 15× scale. If you know the original pinout, you know this one.

The internal wire routing fills the channels between the pin stubs and converges toward the USB-C cavity at the bottom, where all the connections eventually reach the real XIAO.

The wiring harness inside the board. Each color corresponds to a specific pin. Routing wires in a 3D printed cavity is its own puzzle.

Part 3: The brain inside the USB-C port

The real XIAO ESP32-C3 lives inside the giant USB-C connector housing, hidden at the bottom of the board.

The tiny brain of the whole build. The real XIAO fits snugly inside the giant USB-C housing, with every one of its pads wired to the corresponding giant pad above.

The giant USB-C port cover is magnetically attached and has a small hole to pass a regular (not giant) USB-C cable through — so you can plug it in without breaking the illusion.

A real USB-C cable plugged into the giant port reaches the XIAO’s actual USB-C connector.

Part 4: The swappable chip housing

The gray block on top represents the ESP32-C3 chip package. It attaches to the main board with screws, making it easy to swap for a different housing designed for a different use case. It’s designed as a double-door box for modularity, but a single-door design or a different internal layout would work just as well.

The interior of the housing is also swappable — held in place by magnets — so the inside can be completely replaced without disassembling the board. Note: N52 neodymium magnets held the interior in place, but not as strongly as expected — worth over-specifying magnet strength if you build your own.

The chip housing opened.

For workshops and hacksessions, the interior can be configured as a component organizer tray: round wells for small boxes of the XIAO ESP32-C3, and velcro ties for bundled cables. Everything a participant needs in a single package.

The organizer tray in place. The circular wells hold component tins or small modules; the top rails keep jumper cables bundled and accessible.

Loaded up for a workshop. Everything a participant needs for a hands-on embedded session, organized inside a giant microcontroller.

The front detail

The front of the chip box reproduces the original XIAO’s regulatory label — seeed studio / Model: XIAO-ESP32-C3 / FCC ID: Z4T-XIAOESP32C3 / FCC / CE — printed multi-color, exactly as on the original board, just 15× larger.

Bill of materials

Standard PLA filament (black + gray, to match the original XIAO color scheme)
Copper tape (available at any craft or electronics store)
Enameled wire, or any thin stranded wire
A real
M3 screws and heat-set inserts, for the chip housing
A handful of N52 neodymium magnets, for the swappable interior

Files

The printable model lives in this folder: .

Once assembled, flash it with like any other XIAO — the giant size changes nothing about how you program it. See the folder for firmware to try on it.

Rotary encoder

Mon, 01 Jan 0001 00:00:00 +0000

Visit the to download the example code and get the latest version.

A 15× scale replica of the Grove Rotary Angle Sensor from the : 3D printed, wired up, and built around a real potentiometer hidden inside the knob.

The finished sensor. Twist the giant knob, and it turns a real potentiometer underneath.

The concept

The Grove rotary angle sensor is a simple 3-pin analog input: a potentiometer in a small plastic housing, wired to GND, VCC, and SIG (the Grove connector reserves a fourth pin, NC, not connected). It’s the kind of first component people wire up when they’re learning what an ADC reading even means.

The giant version keeps that lesson intact at 15× scale: a real, tiny linear potentiometer (B10K) sits soldered inside the knob, and its three legs are routed out to giant, solderable copper-tape pads on the base plate, laid out in the same GND / VCC / NC / SIG order as the original Grove connector.

Next to its giant XIAO sibling. Same 15× scale, same idea: real components, giant terminals.

Step 1: the base plate

The base plate is split into four printed quadrants (so it fits on a normal 3D printer bed, one big enough won’t need the split at all). Each quadrant locks into its neighbors with a notch, and a small separate key piece bridges the seam and keeps the joint from flexing.

Each seam gets its own key piece, glued in with cyanoacrylate (CA) glue.

Glue every seam and every key piece with CA glue, then let the four quadrants cure into one solid plate.

The finished plate, front and back. The square cutout in the middle is where the potentiometer body will sit.

Step 2: centering collar

A small printed collar glues into the central cutout, between the base plate and the potentiometer body. Its only job is to center the body so it sits flush and square once it’s glued down in step 4.

Step 3: wiring

Four wires need to run from the potentiometer, through the collar, down through the base plate, and out to the back pads. The base plate has a small hole for each wire.

Thread the wires through from the front. A pair of tweezers or fine pliers helps push them through the tight holes. Leave the wires noticeably longer than you think you’ll need: it’s much easier to trim excess later than to redo a wire that turned out too short.

Step 4: gluing the potentiometer body

With the wires routed, glue the potentiometer body onto the base plate, over the centering collar from step 2.

Step 5: decorative pins

Three small pins glue onto the front edge of the body, echoing the three exposed legs of the original Grove sensor’s potentiometer.

Step 6: bearing wells (optional)

The body has four wells sized for standard 608 bearings (skateboard bearings), meant to help the knob spin smoothly. In practice they turned out not to be fully necessary: the potentiometer’s own shaft holds up the knob fine on its own. Consider this step optional.

Step 7: soldering the real potentiometer

Solder the real potentiometer (a linear B10K) into the slot in the middle of the body, one wire per leg. Once it’s soldered in, gently pull on each wire from the back of the base plate to take up the slack left in step 3 and get the length just right.

Step 8: copper tape pads

The last step is turning the wire ends into solderable, touchable pads on the back of the base plate, the same way the giant XIAO’s pins work: copper tape pressed into each shallow pad recess.

Strip each wire and route it into the outermost hole of its pad (the SIG, GND, and VCC pads all carry a wire; NC doesn’t need one, since it isn’t connected on the real sensor either). Make sure the bare wire touches the copper once the tape goes down.

Cutting clean circles and squares out of copper tape by hand is fiddly: a cutting plotter (a Silhouette or similar craft vinyl cutter) makes much cleaner pads than scissors, and it’s worth the patience to set up the cut file correctly before committing the tape.

The result

Bill of materials

Standard PLA filament (blue for the base plate, gray and black for the body and knob)
Cyanoacrylate (CA) glue
Copper tape
Stranded wire, four colors
A linear potentiometer, B10K (10 kΩ)
Four 608 bearings (ABEC5 or similar), optional
A cutting plotter (Silhouette or similar), optional but recommended for the copper pads

Files

The printable parts live in this folder: , or split into four separate print jobs as through (with as the combined project file, and for the flat profile).

Once wired up, it reads just like the real Grove rotary sensor: GND and VCC to power, SIG to an ADC pin. See for TinyGo firmware that reads it and drives a WS2812 strip with the result.

LED

Mon, 01 Jan 0001 00:00:00 +0000

Visit the to download the example code and get the latest version.

📖 Content coming soon.