"Flex ITX" project idea - a tower case for mini ITX cards

CC Ricers

Shrink Way Wielder
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I'm thinking of expanding the idea I started with the Mini LP case and brainstorming another case. This case is based on the frame I have started with Mini LP with a few modifications, and will be bigger. It'll be a more "mainstream" case accommodating full-height cards up to ~210mm in length. I wanted to achieve a tower look with a case that is taller but still not very wide. Imagine something like Falcon Northwest Tiki, but much shorter from front to back.

I am not very good with names so I'm just calling it the "Flex ITX project" for now, referring to flexible choice of compatible PSUs including FlexATX, and for supporting ITX length cards.



Here will be some of the features of the case:
  • "Machined" look assembled out of several aluminum panels
  • Outer walls at least 3mm (1/8 in) thick
  • Tentative dimensions: 33cm x 23cm x 10.5cm
  • Maximum CPU cooler height of ~75mm
  • Storage support: 3x 2.5" hard drives, or 1x 3.5" HDD may be possible
  • PSU support: Flex-ATX, HDPLEX AC-DC, HDPLEX DC-ATX, PicoPSU and similar
  • Expansion slots: 2x full-height
  • Card support: ~210mm length, max height TBD
Overall volume is expected to be around 7.5 to 8 liters. The expansion card will be connected via a flexible PCIe riser with the cooler pointing towards the same side of the case as the CPU cooler. I expect the riser cable length to be about 20cm.

Here are views of the case layout I've had in mind. The case pieces are not final in any way whatsoever.





The white box behind the GPU represents the space for installing power supply components. You can organize cables here, add a AC-DC unit or even fit some power adapter bricks internally.

It's still in the brainstorming phase and I don't expect to begin construction any time soon. I don't even have all the computer parts necessary to begin testing it or demonstrating a full build, but this is a project I'd like to follow through eventually.
 
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iFreilicht

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The white box behind the GPU represents the space for installing power supply components. You can organize cables here, add a AC-DC unit or even fit some power adapter bricks internally.

This seems like the Achilles heel of the whole thing. Whatever you put there, it will get pretty toasty if the GPU is doing anything, unless you can ventilate that area very well. Other than that it seems like a perfectly viable layout.
 

CC Ricers

Shrink Way Wielder
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This seems like the Achilles heel of the whole thing. Whatever you put there, it will get pretty toasty if the GPU is doing anything, unless you can ventilate that area very well. Other than that it seems like a perfectly viable layout.

Yeah, I see a potential hot zone in the space between the GPU and PSU. I plan to add a wall to divide the area, and most of the riser would be exposed to the GPU's backside as well. I don't know whether or not that would help. The side panel facing the PSU will have ventilation holes on the bottom half, though.
 

Colinreay

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I like the idea of it a lot! Question though, I don't have a PCIe riser cable yet, but is the bend radius tight enough for it to make a 180 degree turn in a small space? Reason I ask is that I have an idea floating through my head that is very similar.
 

Kmpkt

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If you use the HDPlex PCIe riser you can do a flat fold on it like paper and it will still work. Most other cables I've looked at are too rigid to do a really sharp turn.
 
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Gautam

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Looks very familiar...similar to what I have on my desk. :p

Yeah, I see a potential hot zone in the space between the GPU and PSU. I plan to add a wall to divide the area, and most of the riser would be exposed to the GPU's backside as well. I don't know whether or not that would help. The side panel facing the PSU will have ventilation holes on the bottom half, though.
My solution was to put fans there. Plenty of room for it if you so choose. The biggest problem is that the PSU will get hot, and in turn get loud, unless its ventilated well.

There's a lot of potential for beefy CPU cooling, and in turn, beefy CPU's, with the type of design you're planning, like a Cyrorig C1. Huge advantage over the likes of the DAN A4.

I like the idea of it a lot! Question though, I don't have a PCIe riser cable yet, but is the bend radius tight enough for it to make a 180 degree turn in a small space? Reason I ask is that I have an idea floating through my head that is very similar.
I'm using a cheapo cable from Amazon, and it does it fine.
 

CC Ricers

Shrink Way Wielder
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If you use the HDPlex PCIe riser you can do a flat fold on it like paper and it will still work. Most other cables I've looked at are too rigid to do a really sharp turn.

I have a Sintech 5cm riser and it also folds very flat, a 180 degree turn. It also holds its shape well.

My solution was to put fans there. Plenty of room for it if you so choose. The biggest problem is that the PSU will get hot, and in turn get loud, unless its ventilated well.

There's a lot of potential for beefy CPU cooling, and in turn, beefy CPU's, with the type of design you're planning, like a Cyrorig C1. Huge advantage over the likes of the DAN A4.

This case would be most suitable for builds using 300W or less. For a possible build using a Intel T CPU that's less than 40W and a GTX 1050 Ti, I can get by with the passive 160W AC-DC power supply by HDPLEX. But I haven't used one of those before, so I don't know how hot that one can get.

And having clearance for bigger CPU coolers is indeed one of the advantages where I'd want to go with. This case would be wide enough to fit coolers such as the Cryorig C1, Shadow Rock LP, or the Thermalright AXP-200.
 

BirdofPrey

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Sep 3, 2015
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I like the idea of it a lot! Question though, I don't have a PCIe riser cable yet, but is the bend radius tight enough for it to make a 180 degree turn in a small space? Reason I ask is that I have an idea floating through my head that is very similar.
Above or below the motherboard? If it's above you should be able to find a hard riser for that
 

Kmpkt

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For the extra ~2.35cm in width, have you considered doing this with an SFX power supply? While I understand you'd probably be increasing the volume by about 20%, I think the value of having a modular and easily available power supply outweighs the negatives of increased volume.

Also with a hard riser the GPU would be facing the wrong way. I just tried it out with a hard riser.
 
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CC Ricers

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Could probably do 300mm x 200mm x 120mm pretty safely with this config.

The idea started out using a SFX power supply but I wanted to make the case narrower. Maybe I'll pursue the design with SFX support later, as it wouldn't be much to change.

Here's an updated design where the case pieces are much closer to what I expect them to be for the actual build.



This X-ray view of just the case more clearly shows how the pieces will be joined. All the pieces can be made from flat sheets and bars, and with no bends. The thickest pieces at the top and bottom are 8mm thick. The front panel is 5mm thick and the rear panel, side panels (not shown) and bars for structural support are 3mm.

 

iFreilicht

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The threads you'd have to tap into the base and top are quite close to the edge, I'd be worried they could break out through the thin wall if the case is getting warped a little bit. Imagine if the base was fixed and you'd hit the case from the back slightly above the mainboard I/O. Even if the side bars are a relatively tight fit in their routed depressions, their sheer length will allow the top to move forwards slightly, creating a huge momentum at the screw joint of the front bars to the base, which could break the thin wall between female thread and top surface easily.

I'd advise to make the second bar below the mainboard as wide as the first one, maybe do the same for the bar in front of the GPU. You should also extend the bars to cover the whole thickness of the top and bottom plate so the threads can be in the mid-plane of those plates for maximum strength. I know it looks cleaner without that, but this construction method is unique, you should embrace it instead of hiding it!
 
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CC Ricers

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The threads you'd have to tap into the base and top are quite close to the edge, I'd be worried they could break out through the thin wall if the case is getting warped a little bit. Imagine if the base was fixed and you'd hit the case from the back slightly above the mainboard I/O. Even if the side bars are a relatively tight fit in their routed depressions, their sheer length will allow the top to move forwards slightly, creating a huge momentum at the screw joint of the front bars to the base, which could break the thin wall between female thread and top surface easily.

I'd advise to make the second bar below the mainboard as wide as the first one, maybe do the same for the bar in front of the GPU. You should also extend the bars to cover the whole thickness of the top and bottom plate so the threads can be in the mid-plane of those plates for maximum strength. I know it looks cleaner without that, but this construction method is unique, you should embrace it instead of hiding it!

The screws that will hold the bars will be either no. 6 or M3.5 being a similar size. There's 1mm of solid wall between the closest end of the holes and the edge, so I could move the holes at least 1mm further inwards. Then either leave it as is or use thicker pieces for the base and top, 9.5mm instead of 8mm.

Making the second bar wider does seem like a good idea. I can then reuse the same bar I cut from the same stock for both mainboard supports and that's part of the convenience I want to keep here- make production as simple as can be with keeping the bill of materials low.

On a different note, the space directly behind the front panel is also large enough for FlexATX or DC-DC power supplies, so I should probably make both that space and the one behind the GPU usable for installing either power supplies or hard drives.
 

CC Ricers

Shrink Way Wielder
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Here's just a render of the case as seen with some parts installed.





This design idea is definitely more for showing off your build. Top and bottom panels are now a bit thicker at 9.5mm (3/8 in.) The side panel can be clear glass or acrylic, and front pieces with intake vents on both sides. It's an element that is already seen in some popular mid-size tower cases.
 
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iFreilicht

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Looks great, I love those vents! Could you make a render with the bars in place? Wonder whether that would worsen the look.

As it is now, you can just leave it like that and have a nice-looking open-air build. Pretty cool.
 
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CC Ricers

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Glad you like them. These renders took over an hour to do :D The other side bars may not even be necessary if the new widths of the other 4 bars are strong enough to support the case in the vertical position. That will definitely make the case look cleaner.

At this point I'm going to start working on the smaller details of the case, like the support wall between the GPU and PSU, and the cutout mounts for hard drives, power button and front USB ports.

I'm also planning out a list of possible purchases to make a BOM (bill of materials) for the case. Some of the metal pieces can be bought from a local hardware store, but some will need to be purchased online. All the screws also will be bought online.

Oh, I also sold the low profile 750 Ti I was gonna use for Mini LP. Trying to use the money to get a 1050 Ti for this case instead XD
 
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CC Ricers

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I ordered the big two pieces for the top and bottom. I will need to cut them to size myself but it would be cheaper than ordering those ends custom cut. Then for the vertical bars, I can grab a .75 inch and 1.5 inch aluminum bar at a local shop for cheap.

These parts would be enough to build the self-supporting structure for the case. More design notes following soon.
 

CC Ricers

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Made a render of just the case frame, which shows the divider panel between the GPU and PSU.



And here's an exploded view.



Design is almost complete now save for the rear cutout for the Flex-ATX PSU. @iFreilicht will probably be able to help with the measurements for that.