Modular Raspberry Pi Mini Rack (Pi 5 / Pi 4 / Pi 3 / Zero 2 W Slide-In Sleds, Fan Walls, PoE Switch Bay)

A modular, slide-in mini rack for Raspberry Pi boards. Mix and match sleds for Pi 5, Pi 4, Pi 3 and Zero 2 W in 3-slot segments, then join segments side by side. Add fan walls, a PoE switch bay, a cable comb and feet.

Designed in SolidCraft. 42 printable parts, each with a print-oriented STL, 3MF and STEP. Every part was checked in CAD:

• All print STLs are watertight and fit a 220 x 220mm bed. The largest is the 130mm deep rail plate, 121 x 130mm.
• No interference in the full 6-slot assembly (57 part pairs, 0 hits), or in the 3-slot test segments: standard, HAT stacks, and 130mm deep with long sleds.

How it works

• The included files are for a 3-slot segment at 35mm slot pitch, 121 x 110 x 80mm (W x D x H). A 130mm deep frame set for long sleds and an 88mm tall end wall are also included. Other pitches and slot counts may come in future versions. It's made of two identical rail plates (the roof is the floor part flipped) and two 8mm end walls, joined with M3 heat-set inserts.
• Sleds slide into 3.1mm grooves with 0.3mm clearance per side, click into a rear detent, and have a front service detent. Each sled has a faceplate with vents and a snap-in label tag.
• Board ports face the rear by default. A flipped sled puts the ports at the front.
• Segments join side by side with key bars and 3 M3 x 20 bolts through the touching end walls.
• The rear panel hangs 30mm behind the frame on top and bottom flanges, leaving room behind the sleds for cables and airflow. Panel options:
• 2 x 40mm fans
• 1 x 80mm fan
• plain vented panel
• PoE keystone panel
• Rear panel flange holes are teardrop shaped, so they print cleanly without supports.
• On top: a switch bay sized for a TP-Link TL-SG1005P (99.8 x 98 x 25mm, from the TP-Link datasheet) or a USB-C hub bay, plus a cable comb. Check your switch's size against the bay.
• Feet: 12mm at the front, 8mm under the rear fan wall. An L bracket is included for shelf or wall mounting.

6-slot demo build

• 2 x Pi 5 with Active Cooler, 2 x Pi 4, 1 x Pi 3B, 1 x Zero 2 W
• About 242 x 140 x 104mm with feet (about 138mm tall with the switch bay on top)
• About 1,056g of PETG (solid CAD mass for 46 parts; real use with 4 walls and 30% infill is lower)

Sled options

• Universal sled for Pi 5 / Pi 4 / Pi 3, in three versions:
• Heat-set insert (default)
• Self-tapping
• Nut trap
• Low-boss universal sled (3mm bosses): use this one for any HAT
• Flipped universal sled (ports to the front)
• Long sled, 120mm, for the 130mm deep frame set (rail plates, end walls, rear panels and comb in 130mm versions). Fits longer stacks such as an M.2 2280 HAT.
• Front-port sled for an RJ45-forward PoE HAT
• Double-height sled for HAT stacks or UPS HATs
• Single and dual Zero 2 W sleds, plus a Zero adapter plate for a universal sled
• Slotted generic sled and strips for other boards (CM4/CM5 IO boards and similar)
• Accessory plate
• Blank filler

Compatibility notes

• Pi 3 Model B can't take a PoE HAT: it has no PoE header (Pi 3B+, Pi 4 and Pi 5 do).
• Pi 5 needs a 5V 5A USB-C supply (the official 27W supply) to run at full USB power. Plan your power budget for a full rack.
• HATs: use the low-boss sled. On the default sled, a Waveshare PoE HAT (H) leaves only 0.19mm to the next slot, and a 10mm tall HAT collides. On the low-boss sled the gap is 2.2mm (PoE HAT H) or 2.0mm (generic 10mm HAT). Put a UPS HAT on the double-height sled. Generic HAT and M.2 HAT heights are conservative guesses, so measure yours.
• Fit: the fan panels, comb and switch bay are sized for the included 121mm wide, 3-slot segment, and fit it as is. The switch bay needs at least 116mm of segment width, so it isn't meant for narrower custom builds.
• The switch bay is sized for the TP-Link TL-SG1005P footprint (an assumed default); check your switch.

Matching Pi cases

• Raspberry Pi 5 case (AI Camera lid, room for AI HAT+ and Active Cooler): https://cults3d.com/:5065232
• Raspberry Pi 3 Model B case (self-tap or heat-set insert base): https://cults3d.com/:5065785
• Pi Zero 2 W case: coming soon

Raspberry Pi is a trademark of Raspberry Pi Ltd. TP-Link is a trademark of TP-Link. This is an independent design, not affiliated with or endorsed by either.

Printed parts for the 6-slot demo build (qty x grams each, about 1,056g total)

• f_rail_plate (floor and roof): 4 x 73.1g
• f_end_wall: 4 x 60.1g
• f_key_bar: 4 x 1.4g
• s_universal: 5 x 27.8g
• s_zero_single: 1 x 28.1g
• m_label_tag: 6 x 0.5g
• m_rear_fan40: 1 x 75.7g
• m_rear_fan80 (or m_rear_vent / m_rear_poe): 1 x 67.2g
• m_cable_comb: 2 x 11.6g
• m_bay (PoE switch): 1 x 51.6g
• m_bay_usbhub (optional): 1 x 37.4g
• m_spacer: 8 x 0.7g
• m_foot (front, 12mm): 4 x 12.7g
• m_foot_h8 (rear, 8mm): 4 x 9.1g

Hardware for the 6-slot demo build

• 24 x M2.5 heat-set inserts (M2.5 x 4; 3.6mm hole, 4.8mm deep), 4 per sled
• 24 x M2.5 x 6 screws (board to sled; HATs bring their own 16mm standoffs)
• 52 x M3 heat-set inserts (OD 4.0 to 4.2, L 5.7; 4.1mm hole, 6.5mm deep). There are 72 positions.
• M3 socket head screws:
• 24 x M3 x 10 (rail plate to end wall)
• 8 x M3 x 8 (fan wall flanges)
• 4 x M3 x 12 (top flange and bay floor)
• 8 x M3 x 10 (bay and spacers)
• 8 x M3 x 16 (feet)
• 3 x M3 x 20 bolts with nuts (segment join)
• 4 x M3 x 8 self-tapping screws (comb to flange)
• 2 x 40 x 40 x 10mm fans (32mm hole spacing) and 1 x 80 x 80 x 25mm fan (71.5mm spacing), with screws
• About 12 zip ties (2.5mm) and 8 rubber pads (28 x 28 x 0.8mm)
• Pi 5 Active Coolers, stick-on heatsinks for Pi 4 / Pi 3B
• Optional: TP-Link TL-SG1005P PoE switch, USB-C PD hub