Open-Frame Case for KAMRUI / NiPoGi / ACEMAGIC AM06 Pro Mini PC (HCAR4000-MI / HCAR5000-MI board) — 120 mm Fan Lid

I wanted the AM06 Pro out of its plastic box and under a proper 120 mm fan, with every port reachable and nothing cut off the stock cooler. This is a from-scratch open-frame tray, inspired by Th3Rom3’s AK2 Plus case (printables.com/model/926938) — same idea, different board, so it isn’t a remix of that geometry.

Fits

• Board: HCAR4000-MI / HCAR5000-MI, 120 × 120 mm, screw pattern 115 × 105 mm (measured on a 5500U unit, V0.3 board). Sold as KAMRUI AM06 Pro, NiPoGi AM06 Pro, ACEMAGIC AM06 Pro, and others with the same board.

• Any standard 120 mm fan (105 mm hole pattern), 25 mm thick works; 15 mm also fine.

What you get

• am06pro_tray_120mm.stl — the case. 145 × 145 × 57 mm.

• am06pro_fitcheck_jig.stl — a 20-minute frame with just the standoffs and a board-outline rib. Print this first to confirm your board revision matches before committing to the 3.5-hour tray.

• am06_tray.py — build123d source. Every dimension (hole spacing, board size, standoff height, clearance, fan hole size…) is a named parameter at the top.

Design notes

• Board mounts inverted: RAM and M.2 face the slotted floor, heatsink faces the fan. The stock blower and shroud stay exactly as they are — the 120 mm sits 30 mm above the board and feeds the blower intake.

• Walls stop at board level, so all four edges are open. No port cutouts to match, works with every AM06 Pro I/O layout.

• The board’s 115 × 105 screw pattern nearly overlaps a 120 mm fan’s 105 × 105 pattern, so the fan posts stand outside the board footprint and reach back in over it with 45° chamfered brackets. No supports needed.

• Standoffs: Ø8 → Ø5 taper, 12 mm tall (clears stacked SO-DIMMs), 2.0 mm pilot for the stock M2.5 screws. Use 2.5 mm pilot (PILOT_D) if yours are M3.

• Fan holes Ø4.3 mm for standard self-tapping fan screws; set FAN_HOLE_D = 4.5 for M4 bolts.

• Floor: vent slots plus 75 mm and 100 mm VESA holes (M4).

Fan power
This board has no 12 V fan header. Use a 5 V USB-powered fan: the Noctua NF-A12x25 5V PWM ships with a USB adaptor — plug it into a rear USB port. Airflow arrow pointing down at the board.

Power button
The stock case’s button connects to JSW1 (4-pin JST, top corner by the mounting hole). Without the case, set Restore on AC Power Loss → Power On in BIOS, or wire a momentary switch to JSW1.

Print settings

• Material: PETG (or ABS/ASA). Not PLA — the heatsink exhaust sits next to the walls.

• 0.2 mm layers, 3 walls, 20–25 % infill, no supports.

• Flat on the bed as exported. 5 mm brim recommended for the 145 mm floor.

• Elephant-foot compensation ~0.25 mm keeps the standoff bases and wall roots to size.

• Tray ≈ 3.5 h / ~100 g. Jig ≈ 20 min.

Assembly

1. Print the jig, drop the board on, check all four screws land. Then print the tray.

2. Pull the board from the stock case: four screws under the rubber feet, pry off the bottom, four more screws. Mind the Wi-Fi antenna leads.

3. Board into the tray, components down, four M2.5 screws into the standoffs.

4. 120 mm fan onto the four corner brackets, arrow down, four fan screws.

5. USB fan cable → rear USB port. Stick-on rubber feet under the corners.