I'm building a tiny case out of laser-cut bamboo

[Barnaby W. Füi]

Well I've found a new problem. I was planning on using a single 120mm intake fan right over the heatsink, so the case has positive air pressure, but it turns out that if you put a grille on the intake side of a fan, it gets quite loud. On the exhaust side, it doesn't change the sound at all. So I need to either put a 1-1.5cm gap between the grille and fan, making the case significantly larger, or try a different approach altogether...

One other idea I've been considering is to use my scythe shuriken's fan for this role. It would take up less space, but I fear the fan might not push enough air to adequately cool both the cpu and case. Then again, i will have no video card, and the only drives are an ssd and a 5400rpm laptop drive. So maybe it would be just fine. Perhaps I need to do some cardboard box mockups.

 

[jchu14]

Very cool project. I've always found very small factors PC to be interesting. I am considering the possbility of gutting an old DVD player and make it into a HTPC. Not as cool as a bamboo case, but it'll fit my HT system better.

Is this computer gonna be used only for web/office duties? Any HTPC functionality planned?

 

[Barnaby W. Füi]

Is this computer gonna be used only for web/office duties? Any HTPC functionality planned?

No htpc or gaming. Mostly just the basics plus programming (which doesn't really need any special hardware considerations other than maybe an ssd).

 

[EarthwormJim]

Very cool. I'm making a tiny case myself out of Lego bricks to house an ATX media center PC. Since I have an Athlon 64 system lying around, I didn't want to spend the money on a small motherboard. I'll still be able to get it tiny with careful placement of the PSU and components.

Is it possible to have your bamboo pieces made with two layers, with alternating grains like plywood?

What did you use to design your cut pieces? Some CAD software?

 

[Barnaby W. Füi]

Is it possible to have your bamboo pieces made with two layers, with alternating grains like plywood?

I guess I could get the thinner bamboo and layer it like that myself, but I really don't want to. Ponoko has plywood available but I just thought the bamboo looked nicer.

What did you use to design your cut pieces? Some CAD software?

I use Inkscape. I probably would use Google Sketchup but they don't support Linux and I hate screwing around with Wine.

 

[Barnaby W. Füi]

I googled and asked and googled, but I couldn't find much data out there about the CPU cooling options I've been considering.

Here are my options:

1. Scythe Shuriken with stock fan
2. Scythe Shuriken with 120mm fan (Yate Loon D12SL-12 (low speed))
3. Intel i3 stock heatsink with 120mm fan

The situation is further complicated because I want to use the CPU fan to also provide airflow for the rest of the case (it will have a cold air intake). This probably rules out #1, as the 100x12mm Scythe fan just seems too puny for such a task.

So I'm left with #2 and #3. The situation is yet again made more complicated by the fact that I don't have any i3 hardware on hand (cpu/mobo/heatsink/ram). I could of course order them, but I enjoy hoping that by the time I get this whole thing designed, prices will have come down a bit, particularly on memory. So what I can do is measure my presumably hotter C2D E6750 with its beefier (taller + copper core) stock cooler, and consider it an analog of the i3 and its stock cooler (with a healthy margin of error to stay on the safe side).

So I did some tests, and here are the results:

Shuriken with stock fan:

idle: 37.5C @ 1721 RPM
load: 57.0C @ 1739 RPM

Scythe Shuriken with Yate Loon 120mm:

idle: 34.5C @ 1278 RPM
load: 50.0C @ 1288 RPM

C2D E6750 stock cooler:

idle: 36.0C @ 1250 RPM
load: 64.0C @ 1406 RPM

C2D E6750 stock cooler w/ yate loon 120mm:

idle: 33.5C @ 1308 RPM
load: 60.5C @ 1298 RPM

These were done in open air, so the temps are a bit lower than they would be inside of a case. The Shuriken + Yate Loon looks like a great combo as far as temperatures go, but I am still tempted to go with the stock i3 heatsink (+ Yate Loon), as it is about 50% shorter (about 23mm, vs 54mm). That is a big difference, considering how compact I am trying to make this machine.

But considering the enclosed case (say, 5&#176 and margin of error (say, 10&#176, the i3 heatsink could get up to perhaps 75C under constant high load. That's pretty alarming, although it's probably the high end of a somewhat uncertain margin of error, since I don't have the real i3 heatsink to test with. Do I take the safe route or the more awesome but more risky route?... I'm leaning towards the latter. Thin is in!

 

[jchu14]

I agree. You should go for the thinner, more awesome route. If you went for the thicker design, you'd always ask yourself if you could've made it thinner

Also, if you ended up finding the the stock heatsink to be inadequate, you could always replace the fan with a higher speed one, or undervolt/underclock the processor. There will be options.

 

[Barnaby W. Füi]

Also, if you ended up finding the the stock heatsink to be inadequate, you could always replace the fan with a higher speed one, or undervolt/underclock the processor. There will be options.

Good point!

 

[Barnaby W. Füi]

My second test print got here today.

Earlier I mentioned using joints like this:

Well, I did a test and got the measurements almost perfect! The bolt hole was only 0.1mm too small, so I'll go with 2.9mm holes for the real case instead of 2.8. 2.9mm is just big enough to let the bolt slide through to the nut without needing to be threaded. The reason that's desirable is so that it's less work to get in and out of the case. I also think I might make the nut slots a tiny bit smaller so that they hold the nut in place without it slipping out and falling who-knows-where.

Pics!

 

[Barnaby W. Füi]

I've been lazy lately, but I think I finally have the layout nailed down.

It's 3.33 x 8.6 x 7.3 inches. I am somewhat tempted to use a 80mm fan which would shave another inch or so off of the height, but I'm not sure the airflow would be adequate. I've also dragged this out for a long time already and I should probably just bite the bullet and finish the thing. I'm sure I'll have other ideas after this first revision, so maybe on the next revision I can experiment with a smaller fan as well.

Anyway, here's the internal view from the front:

Now I just need to draw up all six side panels with tabs/slots/holes and get this thing printed!

Oh, and regarding fan grille noise: I got some normal 120mm fan grilles and they don't seem to cause any air turbulence noise on the intake side of the fan like the fancy hexagonal one did. Too bad. It'll look slightly less cool, but oh well.

 

[alfa147x]

Once you're done I might partak in building one too! Can't wait till you're done!
Great work so far

 

[Barnaby W. Füi]

Getting some real work done!

Back panel:

edit: oops, there's a mistake near the bottom!

 

[EarthwormJim]

Getting some real work done!

Back panel:

edit: oops, there's a mistake near the bottom!

Upside down joint notch?

 

[Barnaby W. Füi]

Upside down joint notch?

Yep!

Whew, I'm all done, I think. Check it out:

And now I've uploaded it to Ponoko and the cost is quite reasonable!

Making $33.50
Materials $14.40
Post & Handling $9.93
Total to PayUSD $57.83

I feel like I should measure 10 times and cut once... but my brain is tired. I'm just going to submit the order and see if there are any mistakes once I receive it. I can always print up revisions of individual parts for cheaper, if necessary.

edit: I just realized I forgot holes for the motherboard and hard drives! Oh well, I can drill them.

 

[Barnaby W. Füi]

Well I've just been sitting around waiting, and finally got a shipping notice today. Should have the parts in a few days.

While I was waiting, I started a website and twitter account. Check them out, if you'd like: http://leastcommon.com http://twitter.com/least_common

 

[Barnaby W. Füi]

Just ordered the components!

Gigabyte GA-H55N-USB3 motherboard
i3 530
Wintec 2x4GB DDR3 1333
PicoPSU 150
120w AC/DC brick

 

[Zap]

I'm looking forward to final build pics... some day.

 

[lhurt]

This looks totally cool. Thanks for sharing your project Barnaby.

Is the power button on the back? And the arrayed slots for exhaust ventilation.

Is it too late the change the design that you submitted? It looks like the large panel with the fan cutout has more mortises than you have tabs on the four thinner edges.

 

[Barnaby W. Füi]

This looks totally cool. Thanks for sharing your project Barnaby.

Is the power button on the back? And the arrayed slots for exhaust ventilation.

Yep. The big circle on the back is the power button, small circle is DC power in, and the array of rectangular slots are for ventilation.

Here's a more orientation-correct version of that last drawing:

The labels assume you'd have it standing up, but you could also lay it down on the large fan-less side, in which top/bottom would become sides, and the side with the fan hole would become the top.

Is it too late the change the design that you submitted? It looks like the large panel with the fan cutout has more mortises than you have tabs on the four thinner edges.

I just realized that the other day. It's too late, but that's okay because I expected such oversights on my first revision. Once I get the chance to assemble it, I'm sure I'll have other refinements to make as well. The thing that sucks is the wait time between submitting a new design and receiving it. I may sign up for Ponoko's "pro" plan which has a much faster turnaround time, but it's $40/mo.

 

[Barnaby W. Füi]

Well I got the first prototype and it was mostly good! There were a few minor things that I expected to need adjustment, and one unfortunately fatal flaw: I screwed up the panel overlapping in my head, and the front and rear panels ended up being too long by two increments of the board thickness.

I also realized that my half-baked idea of mounting hard drives with some scraps of bike tire tube was really stupid, so I adjusted the size of the case a bit (made it slightly less tall, but slightly deeper) so that I could mount the two 2.5" drives on the top and front panels using the screw holes on the bottom of the drives.

I'm also still really iffy on the question of fan filters. I'm leaning towards abandoning the idea due to the need for constant cleaning of the filter, and the noise added by it being close to the fan blades on the intake side of the fan (I'm slowly learning why positive pressure cases are a rarity).

Here are some pics:

 

[EarthwormJim]

That's really neat looking. Are you going to stain the wood or how are you going to finish it?

 

[gorobei]

you may want to start doing your design work on googleSketchup or Blender, it can save you from some simple/silly mistakes.

Not to rain on your parade too much, but some of the elegance of your original design of having a wood case is kind of lost with all these mortise, tenons, and those cross-shaped things. You might want to consider a plastic/metal inner frame for the computer parts, and simpler/cleaner wood panels for the outside. If the panels are only for exterior veneer, you can go thinner stock and reduce some of your costs.

 

[Barnaby W. Füi]

you may want to start doing your design work on googleSketchup or Blender, it can save you from some simple/silly mistakes.

Sketchup doesn't work on Linux and looks really bad in Wine. I played around with Blender a long time ago and all I remember is being boggled by the complexity. I seem to have really hit my stride with Inkscape so it's hard to pull away from it. I think you are ultimately right, but it's just hard to change habits...

Not to rain on your parade too much, but some of the elegance of your original design of having a wood case is kind of lost with all these mortise, tenons, and those cross-shaped things. You might want to consider a plastic/metal inner frame for the computer parts, and simpler/cleaner wood panels for the outside. If the panels are only for exterior veneer, you can go thinner stock and reduce some of your costs.

I'm definitely not designing this for people who want something that looks elegant and classy. That basically either requires hand craftsmanship, or mass production, neither of which are feasible or desirable for me. This is for people who see a MakerBot and think it looks cool. Which of course may be a stupidly small minority of people... I guess I'll find out.

That said, I do have ideas about how to make it a bit less clunky looking and will definitely be trying them out once I get the foundation stable. At this point I'm just trying to get something that works.

 

[Barnaby W. Füi]

Prototype #2 is being made now.

 

[Barnaby W. Füi]

This time, it actually fits together!