Luggable PC PSU Layout

To help optimize arrangement of Luggable PC components, I sketched them out in Fusion 360 so I can experiment with layout in CAD space. I was able to find the specification for the ATX motherboard and power supply, which allowed me to use official dimensions. Unfortunately I wasn’t able to do the same for the PCI-Express cards, because I needed to be a member of the PCI SIG to access the official specs. So I measured and guessed dimensions from the specific implementation I have on hand.

Power Supply Unit (PSU)

As the heaviest single component, I wanted the PSU at the bottom so the overall system is not top-heavy. The question is then: which way to orient the PSU? There were two considerations:

  1. PSU cooling intake: The standard ATX case layout places the PSU at the top of the case, drawing air from beneath. I can’t do that with the PSU at the bottom since a downward-facing intake would be blocked by the table surface. I tried the upward-facing intake once, in the Mini-ITX “Easel Frame 2.0” design. That turned out to be a bad idea because every time I dropped something (usually a screw) it would fall inside the PSU and I have to retrieve it to avoid short-circuiting the internals.
  2. PSU wiring: One side of the PSU takes the standard IEC AC cable. The opposite side is where all the DC wires go to the rest of the components. The decision is then whether to point them front-back or left-right. I didn’t want either of them to point towards the user, so I went with a left-right orientation for the wiring.

Taking care of those two considerations leave two good orientation for the PSU. One with the cooling intake facing front towards the user, or facing away from the user. In the current design, facing backwards allows an unobstructed air path so that’s the preferred position today.

Next post: Positioning the motherboard.

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Luggable PC Gets Fancy Screen

closelidThe latest iteration of the home built luggable computer gets a fancy rotating screen to protect the screen while in transit and hold the screen up while in use.

The time pressure of making it ready for show-and-tell at the February Hackaday LA meet meant I hadn’t been documenting my lessons learned here.

Which is a shame, because there were quite a few 3D printing lessons learned while building this thing. I briefly mentioned a few of them on the project log update up on Hackaday.io but I intend to find the time to expand on those ideas as future posts on this blog. I just hope I can get them all written down before I forget.

Homebuilt Computer now “Luggable PC” on Hackaday.io

hackadayioprojectI’ve known about Hackaday for a while, both the professionally curated site hackaday.com and the public participation site hackaday.io. Some of the people behind the site are nearby which allowed me to easily attend some of their local events.

Most of the project pages I browsed through dealt with Arduino boards, Raspberry Pi boards, or even lower-level hardware. I wasn’t sure if a home built PC is the right kind of topic for the site until I brought my current prototype to one of these local meets. The staffers present assured me that it’d be a great project to document on hackaday.io.

All right then! I’ve created a project page to document my work so far, and I’ll continue documenting future iterations over there instead of here.

One of the Hackaday staffers took an interest in the project, wrote up a short blurb and posted it on the curated hackaday.com. I am very flattered by the attention and it was a great opportunity to see how other Hackaday users viewed the project.

The best comments are from people who appreciate the project and had constructive ideas and suggestions – this is what the site promised for project builders and I’m happy to see it working as intended.

There were a few variants of “This isn’t what I want. I want to see…” and while they are good project ideas, they’re not what I’m trying to accomplish here. Maybe they’ll feel inspired by my project to bring their own ideas to life!

And finally, the comments that dismissed the project. Pointing out shortcomings (some fair, some not) as criticisms without offering anything constructive to address the alleged issues. I just shrug off such criticism and focus on my work.

Positive or negative, the overall quality of the comments are far more articulate and intelligent than your average comment on YouTube.

I call that a win for Hackaday.

Homebuilt ATX All-In-One Computer

Scaling upwards from the previous project, I’m moved up from the Mini-ITX board to a (nearly) full sized ATX motherboard. The larger motherboard required a few more fastener locations but was not a significant challenge. The new challenge in this version was the addition of the GPU and properly securing it to the case.

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Given the triangular profile of the frame, it took a little effort to design the triangular frame to fasten the GPU metal bracket against. At least, as compared to the normal rectangular computer cases. Thankfully CAD software like Onshape have no fear of trigonometry calculations.

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It all works together but I’ve lost most of the size advantage over the standard mid-tower case. Here it is standing in front of the case that used to contain these components.

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While the overall volume is still smaller than the generic PC case, it isn’t smaller by a whole lot. Yes, I do incorporate a screen while the standard case does not, but like the standard case I have a lot of unused empty space in my volume. Even though this made cable management easier and neater, a lot of waste is left over.

I decided the previous Mini-ITX version was on the “too small” side, and we’ve overshot into “too large”. The next iteration of this experiment will try to shrink the design and work towards “just right”


The small 3D printed brackets seen on this page were designed in the OnShape project “Easel PC“, which is available as an OnShape Public Document.

Homebuilt All-In-One Mini-ITX Computer

The previous experiment 3D printed just an enclosure for the Mini-ITX motherboard itself, it didn’t have much of a computer around. This project expands on the idea by building something to hold the rest of the computer components.

The physical size is larger than the build volume of the 3D printer so additional hardware were brought into the equation. Emulating the design for some early RepRap 3D printers, I started using commodity hardware store threaded rods as building structure.

The power supply unit is the heaviest single element and employed to provide the stable base. The new addition to the project is the screen built out of the LCD panel salvaged from an old broken laptop. I used a controller board that translated standard VGA/DVI signal to the panel’s proprietary signal to connect the panel to the rest of this system. Such controller boards can be purchased from one of several vendors on eBay.

The cable management is better than the previous effort, which admittedly set a low bar. The PSU is nice and heavy providing a stable base. Compared to the commodity Mini-ITX case: the overall package takes less desktop space (especially considering the screen) and overall roughly the same volume of space.

easel-back
A better-managed but still a tangle mass of cables.
easel-front
3D printed all-in-one “Easel PC” with a commodity Mini-ITX case.

This is a perfectly usable (if not very neat or pretty) PC. If this were the final goal, I would take a Dremel cutting wheel to cut off the extraneous ends on the threaded rods. Since I have no real need for a Mini-ITX AIO PC at the moment, though, I’m taking the lessons learned and recycling the metal bits for the next project.

Enclosure for Mini-ITX board

Customized computer cases are an interesting area to explore for 3D printing. The home-built desktop PC market is blessed with the luxury of choice, with a wide selection of components a builder can choose from. As a result of this, most desktop PC cases are wide-open designs capable of taking most combinations of components. This directly proves the old adage: “Jack of all trades, master of none.” In contrast, someone with a home 3D printer can custom design for a specific need built around specific components on hand. The result would be a master of one.

Before I can embark on some grandiose vision, I started with a small project built around the MSI AM1I motherboard. It is an inexpensive and highly integrated PC motherboard on the Mini-ITX standard. It had been installed in a Mini-ITX case that, though smaller than most desktop PC cases, still had a lot of wasted volume present to accommodate for components that I never installed.

fullcase
Mini-ITX computer with a great deal of wasted volume.

The Mini-ITX standard restricted the motherboard size to 17cm squared, which is convenient because my 3D printer can print up to 20cm squared. This meant I could print something encompassing the ITX dimension in one piece. I pushed for full minimalism resulting in this design available as OnShape public document “Mini-ITX enclosure“.

emptycase
3D printed Mini-ITX enclosure.

It has screw holes for only the mainboard and the power supply. The large hole on top is tailored for the specific power supply I had on hand, positioning its fan immediately above the motherboard. This allowed removal of the noisy CPU fan as the large power supply fan can pull double duty cooling the whole works resulting in a small neat compact setup.

When I assembled the parts, though, things didn’t look as neat as I imagined:

minimalist
My, what a tangled nest you have.

I had underestimated the chaotic bundle of wires coming out of the power supply. Most of the wires were completely unnecessary and could be cut if this were the final product, but I didn’t want to do that just for an experiment. The remaining wires could be shortened for such a compact layout, but again I didn’t want to break out the wire clipper and soldering iron for sake of the experiment.

The other item I didn’t account for was the storage device, in this case an old SSD in 2.5″ form factor, awkwardly wedged into a slot. (See the red SATA cable in the picture.) I justified this oversight by the fact that most modern ITX boards have on-board M.2 SSD slots, making a separate mounting bracket unnecessary. Truthfully, though, I forgot.

I had fun building this proof-of-concept with old expendable components in case something went wrong. Next custom PC project will be bigger, with more powerful components, and hopefully the wires will be better managed as well!