3.73L Mini ITX SFF PC Case, Two Printed Parts (Stak 3.7 Classic)

only difference between this and the Carry is the shell.

The trick that gets it under four liters: the graphics card and the Flex ATX

power supply stack in one column on the same side of the motherboard. Most

compact cases put them on opposite sides, and that sets a floor on how small the

box can get.

WHAT YOU GET

- 2 STL files, skeleton and shell, in vertical print orientation

- Assembly guide, PDF

- Print settings and material notes

WHAT YOU SUPPLY

- 4x M3 x 6mm hex socket head cap screws

- 200mm PCIe riser cable, if you are running a graphics card

HARDWARE LIMITS

These are hard limits, not comfortable ones. Measure your parts before you print.

- Motherboard: Mini ITX

- CPU cooler: 37mm maximum height

- RAM: 37mm maximum height

- PSU: Flex ATX, 170 x 82 x 41.2mm or smaller, so basically any Flex ATX unit

- GPU: 182 x 69 x 36-40mm, tested with a Gigabyte RTX 5060 Low Profile

The graphics card is held by more than the riser. The riser screws into the base

plate, the backplate is modeled so the card bracket cannot shift, and a cutout

snaps around the bracket to stop it moving front to back.

MATERIALS

I put a thermometer on this under load rather than guessing. The hottest point

inside hit 61.8C, so the skeleton needs ABS, ASA or PETG, anything with a glass

transition above 60C. PLA will soften and warp there over time.

The shell never went past 45C. Print it in whatever you want: glow in the dark,

silk, wood fill, marble. The skeleton does the structural work, the shell is

cosmetic. On this version the shell is a plain box, so unusual filaments read

particularly well on it.

PRINTING

About 12 hours at standard quality on a 256 x 256mm bed. Closer to 22 hours if

you add walls and drop the layer height for a better surface finish. Print the

files in the orientation they come in and you need no supports. Leave supports

enabled and your slicer will generate one small support for the power button,

which is harmless.

AIRFLOW

Passive, no case fans. Air enters through the vented sides and exhausts out the

top and back through the Flex ATX fan and the cutouts. Every face is vented

except the front plate.

WHAT THIS IS NOT

No SFX power supply, it is too tall for the stacked column. No CPU cooler over

37mm. No full size graphics card. If you need any of those, this is the wrong

case and I would rather you know before you buy.

Designed in TinkerCAD, so you get STL rather than STEP. Fine for printing,

harder if you want to do heavy parametric edits.

Want a printed carry handle, reworked vent mesh and rounder edges? That is the

Stak 3.7 Carry, same price.