I like RPis, so much I must have a stack of them! So, why not make the stack pretty and functional?

Cases are nice, but somehow limited, specially when you're always changing uSD cards, hats, using the GPIO, and so on. I have a few cases, and I found myself opening them all the time, or simply not using them at all. On the other hand, leaving my RPies sitting on the table isn't exactly safe for them.

So I figured an open benchtable would be nice, so I built one. But now I had to stack them, so I made it stackable. Now I had to have some fixed to the benchtable, others weren't fixed to it, others needed a fan, so I made it modular. After a few weeks and several iterations, I am proud to share with you what I have created: the 

MOBSS: Modular Open Benchtable Stackable System.

It's Modular because you can expand on it, and use different fixtures to fix your RPi to it, or stack them, or add add-ons. I provide threaded mounting posts (for M2.5 screws) for those using hats that need some mounting point for the standoffs (like the PoE+ hats I have in the photos). There are also toolless mounts for the PIs. Or you can use threaded inserts (it's the perfect size for them), if you want something more permanent. I also provide legs if you want to raise it a bit from the table. You can also add fan mounts, for different sizes of fans, and more modules are being designed.

It's Open Benchtable because it follows the current trend of benchtable chassis, where the motherboard/SBC is exposed, allowing for easy maintenance and access to the components - just like I like my Pies. Also, the “Open” here also carries the meaning of something that is open to expansion, to growth, to further enhancements by the community.

It's Stackable because you can stack several of them, and it's stable as a rock with one or several of them. If you don't wanna use brass standoffs, you can use the included mounting posts, that will integrate fine with M3 screws, nuts or standoffs. 

And finally, it's a System, because it's comprised of several components you can use however you want, although I provide some guidelines. 

Compatibility
 

Although created for the Raspberry Pi in mind, it is compatible with any SBC that shares the same mounting holes as the Raspberry Pis, available here. Currently it is compatible with the RPi 2/3/4/5 and compatibility with the Pi Zero 1/2 is in the works. 

Components explained

Base benchtable: The “chassi” that holds your SBC, and the only required component. Its features are:

• RPi & compatible SBCs mounting holes, compatible with the included mounting posts or threaded inserts (for bronze standoffs)
• Mounting holes for an optional 30mm fan underneath the board
• Mounting holes for optional M3 standoffs or included stacking mounting posts
• Mounting holes for optional legs (optional)

Mounting posts: 

• Provided in 2 flavours: threaded (M2.5) and unthreaded, and both mount to the same holes. 
• Use threaded if you need to screw your SBC to the benchtable or will add standoffs to them.
• Use unthreaded for the flexibility or simplicity of removing your SBC
• The same holes used for them will also perfectly fit threaded inserts (see photo)

Fan mount: (optional)

• Provided for 40x10, 50x10, 60x10 - other sizes available on demand
• Mounting the fan mount on the benchtable requires threaded inserts for M3 screws

Legs: (optional)

• They are a tight fit to the chassi, and quite rigid without any tools, and do not require screws. You can, however, if you want it to be even more rigid, you can add threaded inserts for M3 screws.

Stacking posts: (optional)

• Used to stack benchtables, and can replace bronze standoffs. In the photos, I am stacking the bottom 3 RPis using these stacking posts. 
• Provided in 2 sizes, for use with or without hats
• Can be replaced with M3 standoffs for added rigidity and strength. 

Lug nut: (optional)

• Large M3 lug nut, so you don't need a metal nut to “finish up” the stack. 

Suggested printing parameters:

• Benchtable and legs: any material. 4+ walls, 3+ bottom and top layers. 10% infill (I use lines in 0º and 90)º
• Fan mount: any material, 2+ walls, 10% infill (any)
• Mounting/Stacking posts: PETG (preferably, for the mechanical properties), but PLA will work fine. 4 walls. For the stacking posts, its ok to have low infill, but between its body and the thread there must be lots of infill, so the thread is well attached to the body and won't break easily.