Steam Machine ITX case - Updated v1.1

Overview

For those who like the idea of the Steam Machine but want a smidge more performance and upgrade-ability like that of a conventional ITX PC... at the cost of 50%+ more volume and hacky LED bar integrations.

I designed it around the PC parts I had available and so certain choices/limitations exist around those. The Flex ATX backplate should allow for CPU coolers like a Thermalright PA120 Mini but I opted for the ID-Cooling IS-67-XT so I could use a Corsair SF1000L power supply without worrying about power budget for later upgrades.

Printable Parts

• Baseplate

  • PETG/ABS/ASA ideal

  • Locked Zag infill or whatever settings you might have used in the past for strong parts.

• Backplate (SFX 2x80mm fans OR FLEX ATX 120mm fan)

  • PETG/ABS/ASA ideal

  • Locked Zag infill or whatever settings you might have used in the past for strong parts.

  • Will need supports for small raised areas

• Frontplate

  • PETG/ABS/ASA ideal

  • Locked Zag infill or whatever settings you might have used in the past for strong parts.

  • Supports needed for the usb-a locking tabs/guides

• IO Panel

  • PETG/ABS/ASA ideal

  • Printed face-down, bed choice will affect outward facing finish.

• Front Panel

  • Largely non-structural can be printed however you like however you like

• Lid

  • Designed to be printed with the rear against the bed, shouldn't need supports but might wobble towards the end of the print if the speed is too high, advised printing slowly and perhaps with a larger nozzle to compensate.

• Power Button (either the soft-touch assembly or cherry-style keycap)

  • Button assembly can be printed in any filament - recommended PETG or ABS/ASA if you want to vapor smooth out the concave button

  • The soft-touch assembly backing plate can be whatever.

• LED Bar

  • Ideally Clear PETG - add fuzzy skin to the inner spacing walls to help with light diffusion.

• LED Bar backer - Optional

  • If screws protrude - can also be used as a cable tie-down point)

• Feet - Optional

  • I've provided feet that can be printed in TPU and glued on to the base with a 3d-printed placement guide. Initially I just used standard stick-on rubber feet.

Non-Printable Parts (BoM)

• Brass Threaded Inserts

  • 4x M3 x 5mm for motherboard mounting.

  • 1x M4 x 5mm (at least one for the rear right-side baseplate screw that sits close to the 8pin EPS connector) - You can also just buy a bag of these off AliExpress and use them for all the M4 inserts instead of the longer ones below.

  • 13x M4 x 8mm 

    • 3 for the front of the baseplate

    • 3 for the rear of the baseplate

    • 3 for the IO Panel

    • 4 for the Lid
      

• Bolts/Screws

  • 1x M4 x 10mm Countersunk (For rear right-side baseplate)

  • 3x M4 x  12mm Countersunk (For IO Panel)

  • 11x M4 x 20mm Countersunk (For everything else M4

  • 6x M2.5 - Optional - If using the 3x WS2812-8 modules for the LED bar

  • 4x M3x10mm Countersunk - Recommended (For attaching screw-through magnets to Front Panel/s or Front Plate) - Can also just glue standard 12x3mm magnets to the plates.

  • 4x M3 Motherboard screws (M3 x 4mm~5mm)

  • 4x M1.7x6 Self-tapping screws - Optional - If you're opting to use the power button assembly instead of the mechanical keyboard switch.

  • 1x PC case chassis screw or M4x6mm for the GPU tab.
    

• Washers/Magnets

  • 4x 12mmx3mmx3mm screw-through countersunk magnets (4 per front panel - if you intend to print multiple)

  • 4x M4 Countersunk washers
    

• IO/Electrical Components

  • USB-C Front Panel cable 30cm 

  • USB-A Dual Front Panel Cable

  • Power Button Options

    • 1x Low Profile Mechanical Keyboard Switch (e.g. Cherry/Kailh)

    • OR 1x 6x6x5mm Tactile micro switch (for 3d-printed soft-touch button)
      

  • Power LED options

    • Standard white 3x2mm rectangle LED - Recommended

    • OR a 5v ARGB LED (e.g. a single LED cut off the LED Bar strip or a microbit) - Not recommended if you aren't going down the ESP32 ledbar route - see below
      

  • Assorted lengths of wire (for pwr button and pwr led wiring)

  • Dupont connectors for the aforementioned lengths of wire. (4x single connectors or 2x double connectors should be fine) - More if you want to wire up an ESP32 directly to the USB2 headers.

• Led Bar - Isn't strictly required but can either be:

  • 3x WS2812-8 modules OR

  • a standard WS2812B 5V LED strip cut to length.

  • Both will require some way of being wired to your motherboard ARGB header or ESP32 controller. My advice is get an ARGB splitter and cut off one of the extensions to solder onto the strip/modules.
    
    More on the Led Bar functionality here on my Github page. I've built this to be bazzite-first though it should be fine for other flavors of Linux. It's also worth noting that some motherboards will allow direct led control on their ARGB headers via openRGB, but my ASRock absolutely did not as I found out... If that's the case for you then I'd recommend going down the ESP32 route - details for that are also on the Github repo. 
    
    As mentioned earlier with the Power LED options it is possible to use a single ARGB LED as the power LED when connected as the first LED in the ARGB strip series - the control software can be configured to reserve the first LED as such. If you do go down this route it might be worth checking if your motherboard still powers the ARGB headers in sleep mode - if not, it would be advisable to provide the 5V to the ARGB LED from the ESP32 so that it can still display during sleep.

Assembly

Prep Baseplate and IO Panel with inserts

Pre-populate the IO Panel

If you're opting for the soft tactile button the complete assembly will be screwed into the IO Panel from behind using 4x M1.7x6 Self-tapping screws.

If you're opting for the standard white LED it can be pressed into the rectangular recess.

Solder/crimp the cabling onto the LED and power button; it will be easier to crimp on the dupont connectors prior to assembly but you may want to measure out how long the cables will need to be - 10-15cm should be plenty.

Either way install the USB-C IO cable using the provided screws.

I've opted for the above choices.

Pre-populate the Frontplate

If opting for the 3x WS2812-8 modules, use the 6x M2.5 screws to affix them to the frontplate. If the screws protrude you can use the LED bar backer to cover the exposed screws and solder joins of the modules. Note: The joins are exposed so that the modules can be soldered together in situ.

The USB-A ports should provide their own screws but if not the holes are roughly 2mm in diameter and so any small self-tapping screw should suit.

If you have opted for the mechanical keyboard power switch simply press it into the rectangular cavity on the outside, it will snap into place.

Attach the Backplate to the Baseplate 

Before attaching the Backplate you will need to bend the GPU tab down at a right angle for the GPU securing screw - depending on the filament chosen it can either be done slowly or with a little bit of heat at the join. The reason for this is mostly that it reduces the need to have incredibly thick backplates that so many other 3D printed cases have.

Using the 1x M4 x 10mm on the rear right-side (EPS) and 1x M4 x 20mm on the rear left (under GPU but closer to motherboard) connect the Backplate to the Baseplate.

Note: While these instructions are more about assembling the case itself I will note it's easier to assemble the PC along with it - with that said at this point I would suggest assembling the key motherboard components (cpu, cooler, ram, m.2 etc) now and plug in power cables before they become more awkward to access - some ITX motherboards have EPS power connectors closer to the IO shield and that can be difficult to access when the Backplate has been connected. Fans, especially if you require a splitter, are easier to install now.

Attach the Frontplate to the Baseplate

Using 3x M4x20mm attach the Frontplate to the Baseplate.

Attach the LED Bar by simply pressing it into the two left and right slots - it will click into place.

Attach the IO Panel to the Frontplate

This one is a little tricky as it requires screwing in the IO Panel from within the chassis; and if you've been building along it might be hard to get a standard LTT ratcheting screwdriver in where it needs to go. So for this task I'd recommend using a bendable extension rod (Like in a standard IFixit kit) or a right-angle ratcheting wrench like my Wera Zyklop Pocket.

Connect the Front Panel IO and assemble the rest of the PC

It may also be beneficial to install an intake filter for pet dust..

Secure the Lid in place

Before this step you may want to test the PC to ensure it boots etc - if you need to move it in its current state be sure to avoid flexing it too much, a large part of the case's rigidity is derived from the lid.

The lid slides into to place from the top down (and a little back) and then slides a smidge forward so that its back tabs are flush with the Backplate's recesses.

The weight of the components may cause some slight slanting on the Backplate - this is fine, once the Lid is screwed in from the back the screws themselves will pull the Backplate back to its intended position.

Use 4 of the remaining M4x20mm screws to secure the Backplate to the Lid.

 Securing the front of the lid requires threading the remaining M4x20mm screws through the M4 washers.

Adding the Front Panel

Similarly with the Frontplate lid screw, the Front Panel can use 4 M3x10mm screws to hold the countersunk magnets in place (like washers) - or simply glue standard 12x3mm magnets in the cavity. 

I prefer the screw-through magnets as they can be adjusted by simply backing out the screw to sit flush with the outer rim thus ensuring a close and strong magnetic attraction.

Feet

I have provided a printable foot design that can be glued onto the base of the chassis with a guide to assist in alignment; you can also just use whatever stick-on feet are available at your nearest hardware store like I did originally.

Feedback

All feedback is welcome; and if anyone from Valve sees this please make an official Steam Chassis. 

Changelog

• v1.1 - Added missing lid file(s) - hexagon vented and non-vented