Build guide: parts, printing, inserts, assembly

This guide covers housings v2 and v3. They share the hardware and the steps; where v3 differs, it says so. The steps are the same for every WOODWERD CYD firmware; only the flashing step differs, and each project's own docs cover that.

Everything from ordering the parts to having the case on your desk. Nothing here needs soldering beyond a soldering iron used as a heat source for the inserts. Budget an evening: an hour of printing you don't have to watch, twenty minutes at the bench.

Bill of materials

#	Qty	Part	Spec	Notes
1	1	Cheap Yellow Display board	ESP32-2432S028R, 2.8" 320 × 240 touch, USB-C (2-USB) variant	The case only exposes USB-C — buy the version that has a USB-C port
2	1	USB-C cable, data	USB-C → USB-A recommended	Some boards lack CC resistors; C-to-C into a Mac's C port may not power
3	4	Flat-head screw	M3 × 14 mm, 90° countersunk, hex socket, DIN 7991 / ISO 10642	Length includes the head. Not M3 × 16. 2 mm hex key
4	4	Heat-set threaded insert	M3, brass, 4 mm long, OD 4.0–4.2 mm	The "M3 × L4" kit size; Voron M3×5×4 also fits. Not the 5.7 mm ones
5	1	Printed: Base	CYD_Case_v2_Base.stl or CYD_Case_v3_Base.stl, PETG, no supports	open side up
6	1	Printed: Lid	CYD_Case_v2_Lid.stl or CYD_Case_v3_Lid.stl, PETG, no supports	face down
7	1	Printed: Light pipe	CYD_Case_v2_LightPipe.stl (v3's is the same part), clear filament, 100 % infill	flange down
—	—	Tools	soldering iron (insert tip or clean conical), 2 mm hex key, 3D printer

Same list as a spreadsheet: BOM.csv. Fastener detail with a section drawing: Fastener_Spec.pdf.

1 · Buy

Qty	Part	What to look for	Where
1	ESP32-2432S028R "Cheap Yellow Display", USB-C variant	2.8" 320 × 240 touch display with an ESP32 on the back. Listings say ESP32-2432S028R, CYD, or Cheap Yellow Display. Get the version with a USB-C port (it has both micro-USB and USB-C on the board; the community calls it "CYD2USB" or "2-USB"). The case only exposes USB-C.	Amazon, AliExpress, Banggood — usually well under $20. Two-packs are common.
1	USB-C cable, data-capable	Any phone cable that syncs data works. Some CYD boards lack the CC resistors, so a USB-C → USB-A cable into an A port (or an A adapter) is the reliable choice; C-to-C into a Mac's C port sometimes gives no power.	you have one
4	M3 × 14 mm flat-head screw, 90° countersunk, hex socket	DIN 7991 / ISO 10642. Stainless or black oxide. Length 14 including the head — not 16, the tip would reach the lid face. 2 mm hex key.	any metric fastener kit or hardware store
4	M3 brass heat-set insert, 4 mm long, OD 4.0–4.2 mm	The "M3 × L4" size in most insert kits; Voron-style M3×5×4 also fits. Not the 5.7 mm ones — they bottom out in the boss.	insert kit, CNC Kitchen, Amazon
~30 g	Filament, PETG recommended	Base and lid. PLA works (use a cooler iron for the inserts).	—
a scrap	Clear filament	For the light pipe. Transparent PETG or clear PLA. Natural/translucent works; opaque does not.	—

Tools: a 3D printer (0.4 mm nozzle is fine) · a soldering iron, ideally with an M3 insert tip, a clean conical tip will do · a 2 mm hex key · optional calipers for sorting screws.

Is this screw M3? Hold the bare board over the bin: the screw that drops through a corner hole is M3 (Ø3.0 thread, 5.5–6 mm head). M4 and M5 won't pass. The fastener sheet has a sorting table: Fastener_Spec.pdf.

2 · Print

Files in housings/v2/ or housings/v3/. STL for slicing, STEP if you want to change something.

File	Orientation	Notes
CYD_Case_v2_Base.stl	open side up	no supports; the countersinks are on the bed side and print clean
CYD_Case_v2_Lid.stl	face down	no supports; the display chamfer is on the bed, the bosses point up
CYD_Case_v2_LightPipe.stl	flange down	clear filament, 100 % infill, slow — it's a 5 mm part

Settings that matter: 0.2 mm layers (0.16 for a nicer chamfer), 3–4 perimeters so the lip and groove are solid, PETG at your usual temperature, no supports on anything. Outer size 54.6 × 90.6 × 16.1 mm.

v3: turn on elephant-foot compensation for the base. The RESET and BOOT buttons are cut free by 0.6 mm slots that start on the bed, and a squashed first layer can bridge them. Check both buttons flex before you go on.

Print the base first and try a USB-C cable in it. That's the only fit that matters. If the plug won't click home, sand the lead-in chamfer a little; if your printer runs fat and the lid is tight on the base, a −0.1 mm horizontal-expansion (XY compensation) on the lid is the first knob to turn.

3 · Inserts

Do this before the board goes anywhere near the lid.

1. Set the iron to ~230 °C for PETG (~200 °C for PLA).
2. Rest an insert, knurled end down, on one of the four Ø4.0 mm holes in the lid bosses.
3. Touch the iron to the insert and let the iron's weight press it in — don't push. Keep it straight.
4. Stop when the insert is flush with the boss face. Hold 5 seconds, lift straight off.
5. Let it cool before threading anything in. Repeat ×4.

If one goes in crooked, reheat and nudge it; the boss has room. This is where the insert and the screw sit in the finished stack — the screw comes up from the base, through the board, and gets about 3.9 mm of thread in the insert:

4 · Flash the board on the bench

Flashing is easier with the board out of the case. Use your project's own instructions: Flow Ctrl or ESP Ctrl for any image. Confirm the screen comes up before you close anything up. If the port doesn't show up, hold BOOT while plugging in.

5 · Assemble

1. Push the light pipe up into its tube on the underside of the lid, flange against the ceiling.
2. Drop the board into the base, USB-C end first, so the port seats in the lower half of its opening. Screen up. The four corner holes line up over the standoffs.
3. Lid on: the tongue over the port goes into its slot, then the lip drops into the groove all the way round. It should seat with no force; if it doesn't, something's under it.
4. Flip it over and drive the four M3 × 14 screws from below, 2 mm hex, snug with the short arm of the key. It's plastic — stop when the head sits in the countersink.
5. v3: slide in a microSD card if your firmware uses one. Push until it clicks; push again to release it. Press RESET from below to restart the board; hold BOOT while pressing RESET for download mode.

6 · Then

Go back to your project's getting-started guide. The light sensor works through the pipe; the RGB LED may show faintly through lighter filament.

What's covered on purpose

On v2, micro-USB, the microSD slot, the RESET / BOOT buttons and the JST headers are all inside. Housing v3 opens the microSD slot and adds printed RESET and BOOT buttons. Micro-USB and the JST headers stay inside on both; the STEP files make small edits easy.