Building Case from scratch

[Bonfius]

Hey everyone,

 

I want to build my own PC case from Scratch. Bad idea. I know. I cheaped out on my case I bought in the first place, so dont buy too cheap… it will bite you in the ass. 

 

So I am close to summer break form University, I am a mechanical Engineering Student, so I know some stuff. 

Here ist my plan: Building a relatively "normal" case. the structual components should be made out of some boring old steel, like DIN E296 or so. I plan to use L-brakets for the case, the steel itself for the motherbaord tray, fan Mounts, backside… I am not sure yet if I should have someone laser cut it or try my luck with the angelgrinder. The visisible Panels should be made of some nice Stainless steel. Additionally I had the idea, to put the fron IO into a box-ish ontop of the case to be able to swap it out (for example the USB types…)

 

Yes I will Model it in CAD/SolidWorks before getting any materials… I am currently making some final-ish scatches and General sizing.

 

Anyways has someone done something like that before? 

What were issues you had ? 

 

Feel free to link me other posts to read.

 

Stay save!

 

Jan "Bonfius".

 

(If you are interested I can poste some of my drawing/scatches later when they are somewhat useable) 

[W-L]

1 minute ago, Bonfius said:

-SNIP-

Welcome to the forums!

 

I would recommend to start with a motherboard tray that you can buy off the shelf and start from them, depending on what you want as design and concept you are looking to achieve. There are certain places that specialize in one off parts but just note the cost of doing something like will be quite high. 

https://www.mountainmods.com/product_info.php?products_id=56

[Bonfius]

10 minutes ago, W-L said:

Welcome to the forums!

 

I would recommend to start with a motherboard tray that you can buy off the shelf and start from them, depending on what you want as design and concept you are looking to achieve. There are certain places that specialize in one off parts but just note the cost of doing something like will be quite high. 

https://www.mountainmods.com/product_info.php?products_id=56

Thanks...

I know it is the most Logical and reasonable Thing to do from going from a cheap ass case to a custom one… I am well Aware of the costsfactor

 

Found a german dealer for  motherbaord trays as well as PCIe brakets.

[W-L]

2 hours ago, Bonfius said:

Thanks...

I know it is the most Logical and reasonable Thing to do from going from a cheap ass case to a custom one… I am well Aware of the costsfactor

 

Found a german dealer for  motherbaord trays as well as PCIe brakets.

If you provide them engineering drawings that will really help drive down the costs. One that has been used by Linus is Protocase which specializes in custom fabrication and one off parts. However I believe they are based in Canada. 

[startrek03]

I want to do something similar and I already have most of CAD drawings. While I want to rely on wood for the outer shell, I want to use steel for the inner parts aswell. I did sort of a mod/custom case before, which failed catastrophical in my opinion and I learned a couple of lessons, that at least apply to me. You probably know them because your a mechanical engineering student, but however.

Big blank sheet metal surfaces are wobbly. Obviously. I know. But the motherboard tray is one of these surfaces and especially the area next to motherboard is prown to that. And the bottom, depending on the way you mount it might also be problematic because you need some sort of feet and these feet need to be mounted on a stiff surface.

Another thing to consider is the placement of buttons, front I/O and mounting of other stuff.

You've probably thought about all that, but it can really bite you in the ass, if you didn't. That's what I learned at least.

Good luck of course!

 

PS: Could we get some some screenshots of your drawings? I'm actually quite curious.

[Bonfius]

14 hours ago, startrek03 said:

I want to do something similar and I already have most of CAD drawings. While I want to rely on wood for the outer shell, I want to use steel for the inner parts aswell. I did sort of a mod/custom case before, which failed catastrophical in my opinion and I learned a couple of lessons, that at least apply to me. You probably know them because your a mechanical engineering student, but however.

Big blank sheet metal surfaces are wobbly. Obviously. I know. But the motherboard tray is one of these surfaces and especially the area next to motherboard is prown to that. And the bottom, depending on the way you mount it might also be problematic because you need some sort of feet and these feet need to be mounted on a stiff surface.

Another thing to consider is the placement of buttons, front I/O and mounting of other stuff.

You've probably thought about all that, but it can really bite you in the ass, if you didn't. That's what I learned at least.

Good luck of course!

 

PS: Could we get some some screenshots of your drawings? I'm actually quite curious.

By now I am pretty sure to buy the motherboard tray, as well as part of the back with the cutout for the IO shield and the PCIe brakets. 

For the base i want to use a generic steel plate like 2-3mm thick. For the front IO I am not sure yet how to do; the one more conservative approach is, to put them on the out (into the top) the other Idea i had was a set top box, on the chassis, were I can change with relative ease the front IO. Ill make some better drawings soon of this idea and post them.

 

I did the skeleton construction yesterday (In CAD) planing to use 15x15xN L brakets from aluminum (1mm thick) . I eyeballed the strength but didnt to the proper calculations to be honest.

 

I think I have a lokal Metall company to cut front fan mounting plate.

 

Curently I just have coffee soaked pencil scetches, I dont think there are worth uploading, but I have have some more Parts in CAD and for some parts some more precise drawings ill share them for sure.  

[startrek03]

These two documents will help you with measurements for ATX and PCIe:

• ATX specifications: https://cdn.instructables.com/ORIG/FS8/5ILB/GU59Z1AT/FS85ILBGU59Z1AT.pdf
• PCIe specifiactions: http://read.pudn.com/downloads166/ebook/758109/PCI_Express_CEM_1.1.pdf

I've used them to get my CAD correctly. You probably don't really need them anyways because you're buying a tray. However, it might help to understand some measurements. and spacings

[Bonfius]

@startrek03 here is a little update. 

-needed to do changes after I bought a L-Bracket and did some testing and trying.

- I thought using 10mm stainless steel was a good Idea. Well per side panel would have been like 17,5 kg... didn't do the calculation for the other panels for reasons... opted for 2 mm stainless steel instead. still 3,5 kg per side and front/top/botton each 1,7 kg

- Found out I cant make holes with a precision of 1/10 of a mm soo I added more tolerances 

- hopefully my calculations for the dimensions and especially screws are correct.

- already designed the front plate/panel I might add it into the assembly...maybe not. 

 

- finishing up the drawings for all the plates and panels I need to get made, so I can talk to lokal companies

[frokes]

Hi! I think your concept and ideas are solid and that you are on the right path!

Keep in mind however that those fancy stainless panels will be prone to flexing and bending (even if they are 2mm and screw/rivet them to the frame) if you do not add any bends or reinforcements to them. These things tend to not show up in CAD but you'll forever look at the distorted reflection on the sides and regret not reinforcing them. I'd also go with thinner material as 2mm stainless gets pricey in no time and really does not serve a purpose if you engineer the panels correctly.

 

Other than that I can't really say anything as I've always opted for internals out of acrylic or PMMA on my cases as they are way easier to work with.

 

Good luck!

[startrek03]

21 hours ago, Bonfius said:

@startrek03 here is a little update. 

-needed to do changes after I bought a L-Bracket and did some testing and trying.

- I thought using 10mm stainless steel was a good Idea. Well per side panel would have been like 17,5 kg... didn't do the calculation for the other panels for reasons... opted for 2 mm stainless steel instead. still 3,5 kg per side and front/top/botton each 1,7 kg

- Found out I cant make holes with a precision of 1/10 of a mm soo I added more tolerances 

- hopefully my calculations for the dimensions and especially screws are correct.

- already designed the front plate/panel I might add it into the assembly...maybe not. 

 

- finishing up the drawings for all the plates and panels I need to get made, so I can talk to lokal companies

Keep in mind that you have sort out the mounting of the motherboard tray somehow.

[Bonfius]

On 8/19/2020 at 5:57 PM, startrek03 said:

Keep in mind that you have sort out the mounting of the motherboard tray somehow.

yep. I changed my mind XD. Our Italien friends who wanted to give me drawings of their motherboard tray are currentlny on vacation and told its basicall faster to buy the tray and messure it myself. Well I found out that I can have an ATX PC case from a big box retailer for ehmm 20 bucks instead of MBTray and BackIO/PCIe for 60-80... guess who is gonna pick it up today and take it apart ;). 

Mounting: L-Braked in the back, 2nd L-Braked at the ende of the tray probs mounted to the bottom. But a lot of these things ill test and decide when I salvaged the parts from the case, know their dimensions.....

 

Yes it seems to be cheaper to buy a new case and destroy it instead of buying a used one. thats crazy.... 

[Bonfius]

On 8/19/2020 at 4:29 PM, frokes said:

Hi! I think your concept and ideas are solid and that you are on the right path!

Keep in mind however that those fancy stainless panels will be prone to flexing and bending (even if they are 2mm and screw/rivet them to the frame) if you do not add any bends or reinforcements to them. These things tend to not show up in CAD but you'll forever look at the distorted reflection on the sides and regret not reinforcing them. I'd also go with thinner material as 2mm stainless gets pricey in no time and really does not serve a purpose if you engineer the panels correctly.

 

Other than that I can't really say anything as I've always opted for internals out of acrylic or PMMA on my cases as they are way easier to work with.

 

Good luck!

Thanks for the hint. 

the strength of the steel for me its really dependent on what the company has and whats priced, if they have scrap.... 

The flex/bending how bad is it? 

I did my guesses with 10 mm steel, but I definitely need to check that stuff out. I thought about aluminum, buts its far to easy to bend and scratch it...

[frokes]

3 hours ago, Bonfius said:

The flex/bending how bad is it? 

That's really hard to say. If you end up going for 2mm then it might not be bad at all but at 1mm it might be quite severe.

 

3 hours ago, Bonfius said:

the strength of the steel for me its really dependent on what the company has and whats priced, if they have scrap.... 

Gotcha, most companies I've had contact with are quite relaxed when it comes to scrap and the pricing of it. To give you a reference, prices might vary for you, we charge 8 - 11 €/kg at our makerspace for stainless (304 I think...) which is basicly the price we buy it for, scrap prices are a bit lower.

You could also have a look at regular mild steel ( usually 1.5 - 3 €/kg ), though you'd have to coat/paint the surface in that case.

 

I'd love to see a build log once you start building, I think it could look really nice!

[Bonfius]

@frokes @startrek03 @W-L

so here is an update:

all drawings (finally) done. Will go out next week to find someone ....

bought a cheap case

took it apart

made rough 3D-models of the parts a want  to use and added them to my model (at least in the model everything fits fine)

used this case as donor: https://www.notebooksbilliger.de/pc+hardware/gehaeuse+pc+hardware/inter+tech+b+30+pc+gehuse+414453

to be honest: for the money its great. No sharp edges, its somewhat stable and has structural integrity. Definitely could be worse. 

 

Jan

 

(fun fact: it took me 12 min to take it completely apart. a decend 3mm drill does wonders for rivets)

[frokes]

Nice progress! The backplate from any case, no matter how cheap, will save you so much time and frustration later on :P Keep it up!

[PriitM]

2mm stainless is stiff and heavy enough that you wont have any vibration issues. If you want the same sort of stiffness but have it a little bit lighter (20% on average over steel), you can go with 4mm aluminum. Also, aluminum extruded stock is somewhat more accurate, so I would go with that on the joints. 

 

Tho I would still up the screw/bolt connection amount everywhere part from the side panel. At least 3 on the longer sides, better 4. That way, you dont have to make a skeleton frame out of angle, but use the panels as structural components. Save on fabrication/assembly time. 

 

Side panel opening has several options: have it hinged, with magnets or bolt it. Listed in the order of the most difficult to mount vs easiest to use

 

One thing you have to remember is that stock is never 100% perfect. The angle stock may not be straight nor 90 degrees. I would suggest you revise your drawings to have overlapping joints. That way you can hide some imperfections from the stock. Might not sound pretty, but will be worth it in the end

 

The final finish of the case is up to you: stainless usually has a really nice satin gray scale...which get scratched really easy. Going fro scrap will probably be scratched to all hell...and you cannot fix that. If you do commit to redoing the finish on it, I suggest you avoid polishing. You will fall into a deeeeep rabbit hole of grit, compounds, polishing discs and painfully slow progress. Brushed finish means the same prep as for polish, but you use a big scotch brite pad to create the uniform look. Then there are chemical options to pickle/etch. Painting is always an option. You could, if yo get the chance, go pre-brushed/polished. They have the protective plastic peel, that can help you when fabricating. The above applies to aluminium too. 

 

If you are looking to put some beauty features on the case, a light chamfer on the outer edges would complete the look. 1/3rd of material thickness in size is usually the "golden ratio". 

 

Dont bother with front IO. The cases I have built from scratch, I did put IO slots...but very rarely used the front USB/audio. A simple powerswitch and reset button is pretty much what you actually need. Since 99% of data is now on the internet, I rarely use a USB stick anymore...

 

I would compact the case as much as possible. This way you save on material, increase stiffness and wont have to run the fans as hard to cycle the internal volume. Last 2 cases did not have HDD racks. 1TB main SSD with an external "vault" HDD. 

 

Great start, looking forward to the build

[Bonfius]

so I sent my drawings to a steel company. waiting for their offer.

I got a nice date with Solidworks Visualize today, after a little bet of tweeking the settings (and finding out my ryzen is fucking slow and SW refuses to use my Vega) I did some renders...

 

[Bonfius]

Update: Waiting Non-Reference specs (sizing) of the RTX 3070