Prototype Knarr: ~12L case with a focus on liquid cooling and aesthetics

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
Project Knarr

This was designed as a liquid cooling oriented case with the capability of supporting a full custom liquid cooling loop, a 240mm radiator, or potentially two 120mm radiators for hybrid cooled GPUs + cpu AIO configurations.
This is the update to an existing prototype that you may have seen here: https://smallformfactor.net/forum/threads/not-a-sandwich-case.11954/



Specifications:
Total: 315mm x 317.7mm x 135.2mm as designed (manufacturing tolerances may vary due to dimensional stability of wood)
Core: 307mm x 305mm x 127.2mm including window side panel (does not include wooden overhangs)
Internal: 305mm x 305mm x 123mm = 11.44L internal volume

Hardware support:
Motherbaord - ITX, max 100mm tall cpu cooler.
GPU - 2.5 slot, up to 300mm in length.
PSU - SFX or SFX-L however SFX is recommended for easier cable management.
RAM - dependent on cpu cooler clearance.
SSD - up to three (3) standard 2.5" SSD - (7mm thick, dependent on choice of radiator)
Front panel IO - none. Power button located on top and is wooden to blend with the design. No power LED.
Riser cable - designed to work with a 20cm riser cable with 108mm hole spacing (LINKUP - the only ones i found so far that are offering a pcie4.0 compatible riser soon)

Cooling support:
CPU - Air coolers up to 100mm tall. Note window side panel does not have vents above the motherboard.
GPU - Choice of vented Plexiglas side panel or not vented glass panel for liquid cooled or hybrid cards.
FANS - Up to two (2) 60mm fans on rear panel. Up to two (2) 120mm fans on side panel.
Liquid:
one (1) 240mm radiator, or two (2) 120mm radiators arranged with abutting tanks (tubes exit on opposite sides, bottom tank < 12mm this is untested but should in theory be possible). The two (2) 120mm radiator configuration will eliminate SSD mounting entirely.
D5 pump with custom reservoir top integrated into back panel - replaces two 60mm fans.
DDC pump with most aftermarket tops and pump mounted reservoirs up to 150mm tall in front of radiator (30mm thick), above GPU. Recommend using smaller reservoirs to make filling easier. No custom mounting brackets for the DDC yet but there is one in the plans.

AIO on cpu with vented side panel:


AIO on gpu (Kraken G12):


Full custom loop (D5 with custom reservoir in place of 60mm fans):


Alternate custom loop with fully internal EK-xres-100 DDC

Color options:
White - Solid Maple top/bottom.
Grey - Solid Walnut top/bottom.
Black - Solid Wenge top/bottom. (subject to change)



Currently I am working on evaluating the first prototypes and ease of assembly, how easy it is to build in, and thermal performance. If i commit to making a small production run, something like 100 units, the target "retail price" for this case would be $225 USD (including riser cable) but is subject to change based on volumes, material choices, and manufacturing partners.

Thanks for looking!
 
Last edited:

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
First prototypes are almost complete. Just missing power buttons for now but i couldn't resist showing everyone a build.

There were definite issues with production. The tolerances on the wood are very... variable. Maybe its my hobby CNC or just the wood changing dimensions slightly with temperature but i had the worst time getting the metal to mate with the wood. As a result, you can see some epoxy around the seam, some units are not perfectly square (although they are close to it), some wood has cracked a little around the seams, and some metal is bent here and there (from gentle persuasion with a rubber mallet). Definitely need to rethink this. Currently have two ideas, either make the groove in the wood grossly oversized so the panels just drop in or rethink the use of rivets to have a metal top and bottom panel also, with the wood becoming just a decorative element instead of a structural one. I am leaning towards the latter although that would likely make the whole thing a little bit bigger.

Anyways, they look nice still. Prototypes:





Now for the build. Compared to the first case i made, this iteration (this is actually version two) is MUCH easier to build in. I got my computer built in it in under an hour. All the actual pc hardware fits absolutely perfectly. So im happy that the tolerances in that regard are solid. Will make the next batch of prototypes easier as i have real world proven dimensions for internal layout to go by.



Edit: I got the power button and acrylic side panels laser cut. I would now call the first prototypes finished:

 
Last edited:
  • Like
Reactions: dealda and bricemx

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
Some preference testing!

I didn't have time to try all the different fan configurations yet so I did all the below testing with rear 60mm fans set as intake, and the side 120mm fans set to exhaust through the radiator.
GPU fan on the blower cooler was limited to 85% fan speed. Ambient temperature of 22.5 C, and all tests were done with 10 min of aida64 for both loading and logging.

Overall I would say the temperatures are very much in check. The vented side panel vs no side panel at all makes no difference so the vents are definitely working :). The fully solid side panel sees GPU temperatures Spike up about 4 degrees, as expected. I would like to flip all fans to intake to create positive pressure and see if that affects the temperatures since it's a blower cooler.

 
Last edited:
  • Like
Reactions: Poblopuablo

Allhopeforhumanity

Master of Cramming
May 1, 2017
446
440
The wood panels look great, but given their non-standard size, it might be easier/cheaper to do an inlay of a standard size rather than a whole side panel.

Another criticism is the amount of airflow, particularly in the external D5/DDC configuration. If the radiator is exhausting, that leaves only the front ports for air ingress unless you get a vented side panel. It might be worth exploring opening up the front a bit more, and utilizing the bottom as an exhaust.

Looking forward to seeing this project progress.
 

duynguyenle

Cable-Tie Ninja
Aug 20, 2019
159
146
Would you be open to investigating the cost differences by making the panels out of laser/water jet cut metal sheets instead of wood? Would the design be viable (I haven't really looked closely at the photos as I'm on my phone at the moment).

I am not really keen on wooden cases as it's more unpredictable (especially given repeated frequent thermal cycling nature of this application).
 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
For airflow concerns, I can look into adding a 92mm fan in the top wood panel above the motherboard. That should be doable and would still look good.

For all aluminum construction, I didn't want to go that route because I think wood looks good. Its part of what makes this case look nice. Also the original prototype had an aluminum top and bottom which required welding and made the whole thing very cost prohibitive. But the original prototype has a large wooden panel as well sealed with polyeurathane and I have experienced no warping or cracking at all so far.
 
  • Like
Reactions: Poblopuablo

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
So I looked into adding a top fan and concluded that it will not work. There just isn't enough room. In my mind (I plan to do some thermal testing on a prototype) if all fans exhaust then air intakes through the vented side panel and helps the gpu along in cooling. If the side panel is not vented then likely your gpu is liquid cooled in which case you can swap the rear fans to intake. I can however add some vents to the bottom of the case so that if you have the pump mounted in the back instead of fans there is a little more ventilation for the radiator.
 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
What is causing the lack of room? Motherboard components?
Basically yes. The motherboard is only 5mm away from the wood so the fan has to be offset towards the window (already didn't look nice) and if you wanted to have any hope of plugging in your cpu power cable you'd need a fan smaller than 70mm. So not great no matter how you look at it.

Technically if I grew the whole case 10mm in height you could fit a 120mm slim fan up there above the motherboard. Most probably even two... But until I do some thermal testing on the existing design I don't want to commit to that growth. I am not convinced the current cooling configuration is inadequate
 

the1q

Caliper Novice
Jun 3, 2019
30
49
Could you make the top and bottom wood panels interchangeable? That way you can flip the orientation of the case and still see the glass side.

I also wouldn’t mind seeing all the sides in aluminum with the top and bottom in wood. I think it would still look good.
 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
I made a quick ddc mount for the 240mm radiator. Not necessarily final version of it but it will let you mount something like an EK XRES 100 with a DDC completely internally in front of the radiator and thus, will preserve the dual 60mm fans in the back for added airflow. The pump position can be adjusted to be farther away from the front vents and this does require some creative tubing runs. Also updated renders in first post with this and other cooling configurations while i sort out prototyping. I thought i got a good deal on 4 units from a local manufacturer but it fell through so im still actively looking for others.

 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
Could you make the top and bottom wood panels interchangeable? That way you can flip the orientation of the case and still see the glass side.

I also wouldn’t mind seeing all the sides in aluminum with the top and bottom in wood. I think it would still look good.
Why cant you just... flip it over? And put it on your desk up side down? There are two design elements that prevent the wood from being interchangeable. Most importantly, its epoxied together. So you wouldn't be able to take it apart to do the swap. But also importantly the glass panel does not actually screw onto the case. It slides on from behind in grooves that are milled into the wood and there is a small tab on the back to prevent it from sliding back out:



As for aluminum instead of glass side panel, i can whip up a render for you. Technically you could slide in any material panel you want instead of the glass although it would be a bit thinner (groove designed to accommodate 1/8" thick acrylic or glass).
 

Poblopuablo

King of Cable Management
Bronze Supporter
Jan 14, 2018
738
381
Dude your renders are so awesome! I'm loving this case more and more! (I just wish it had dual 240 mounts lol... But that's just me.) The size and aesthetic is amazing!!
 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
Power button. If you located the power button somewhere else then....brilliant. The sliding panel is great! Opens up other possibilities.
Ooooh you are right. Hmm I don't want to put it on the front because it kind of ruins the look. The power button pcb however is just screwed into the wood directly. I could create the same circular cutout on the bottom and you could optionally relocate the button if you chose to flip the case over. I don't think it's a big deal to have a hole at the bottom since you would never see it, or you could repurpose it for a drain port...
 
  • Like
Reactions: the1q

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
Small update. I finally managed to find a local manufacturer and we worked out a reasonable quote for a few prototypes. So this is finally slowly moving into reality. Stay tuned for prototype photos in the following few weeks.
 

warmack

Trash Compacter
Warmack Woodworks
Gold Supporter
Nov 4, 2018
40
43
Loving the wood! What kind of issues are you having with the non-standard size?
 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
Loving the wood! What kind of issues are you having with the non-standard size?
I'm having a hard time finding a 5.5" board that is 1/4" thick (but I think I have found it... Need to go to the place and check it out). I don't want to get thicker because it's wasteful to machine it away and I don't have the tools to get something like a 3/4" thick and rip it in half/plane it
 
Last edited:

warmack

Trash Compacter
Warmack Woodworks
Gold Supporter
Nov 4, 2018
40
43
Gotcha. What kind of tools do you have access to? You could get a 3-4" piece and resaw that on a table saw and then glue it up to make a larger panel. Resulting size might be close enough to what you need for a prototype at least. You'd probably get a piece that is more dimensionally stable as well. It's gonna be harder to find a 5.5" board that isn't flat sawn.

Let me know if I can help in any way. I'd be happy to send you some walnut at cost for your prototypes if you want, though I am not sure how affordable shipping would be from US to Canada. I'm finding out shipping to AUS is expensive for just a small wooden panel
 

Shatrod

SFF Lingo Aficionado
Original poster
Dec 6, 2019
128
151
I have a sheet metal brake, Arbor press, some hand tools and a CNC mill. Nothing that can resaw a thick board. I could use the CNC and just mill a thick board down to 1/4". If I can't find stuff that is already 1/4" I will likely do that.

I appreciate your offer! I may send you a message if the shop I found somewhat locally in Canada doesn't have what I need.