NUT Case

NUT Case - A Novel UtiliTarian Case for Mini-ITX motherboards

I began this project to meet the needs of many people who are looking for a Mini-ITX case that can print on Ender 3 and similar sized printers, including myself. Seems like they don't live here on Instructables. I expect to add a few pieces to expand the options available as my time permits, if there is some interest shown.

If you are interested in this project and would like to see additional development, please drop a comment. I have been having some trouble seeing updates post on this project. Pictures would change but the text didn't? Refresh some more. Try again. Sometimes it's days to see a change actually post. That's been a frustrating bit of using this interface. The Power Supply section went totally corrupt so I deleted it.

A little background.

I selected a Mini-ITX (6.7" x 6.7") motherboard since many systems in this class are just as capable as their larger cousins on the north bridge, just limiting the number of slots available. For instance, you will find only 2 memory slots on this small motherboard. But with each slot supporting 32 GB, you can still have a system with 64 GB of RAM if you like.

Many of these boards now support two M.2 NVMe drives, two RAM slots and limit the number of PCI expansion slots to 1. Four SATA ports are standard. Onboard graphics and audio processing is sufficient for 2D games and office applications, so I decided to initially not use the PCIe slot. Maybe a future remix will support a graphics card. This makes the Mini-ITX form factor great for a small build as the system drive is mounted directly on the motherboard.

To Make a NUT Case you need:

A basic 8" 3D printer - 210 x 210 x 180 mm build space or larger
. (I used Anycubic i3 MEGA-S and Creality Ender 3 printers)

• 1 kg Inland PLA+ worked well for me
• great with multiple colors for various parts
• your basic 3D printer tools (what ever works for you)
• My custom files to print this have been removed.

These items typically come with commercial cases;

• power switch and indicator LEDs or modular computer power switch
• 120 mm case fan (I use 4mm nuts and 4 mm x 30 mm screws to mount)
• Misc screws for motherboard and drives

The following items are what I put into this case. But it's your system, so buy what suits your needs. I use these parts to demonstrate the basic elements of assembling your own system. RAM, M.2 NVMe drives, 2.5" drives and CPU are dependent on your choice of motherboard!! Please search other sources to determine what sort of system you need, as motherboard details will change over time. This Instructable is about building a Mini-ITX system in the NUT Case.

• Semi-modular ATX power supply
• Mini-ITX motherboard (Intel LGA 1200) and matching i5 CPU with cooler
• 32 GB RAM - 2 x 16 GB or 2 x 32 GB for 64 GB total
• M.2 drives and/or up to four 2.5" drive - entirely up to you
• CD/DVD multi drive or I/O panel insert (optional)

misc screws; most of the hardware will come with your components

• four #6-32 x 1/4" screws (for motherboard)
• four #6-32 x 1/4" screws (with power supply)
• four 4 mm x 35 mm screws (or use fan supplied mounting hardware)
• four 4 mm hex nuts (fan)
• four 3 mm screws (provided with optional 2.5" drives, I hope)
• thirty 4 mm x 6 mm screws (case, optional if printing PR5x pin rivets)
• thirty 4 mm nuts (case, optional if printing PR5x pin rivets)

Overview

Here's a few notes on the major pieces to make this case. I was about to make an adjustable side panel and air intakes for the standard heat sinks, but due to a lack of interest in this project, I am suspending work on new pieces.

mITX_MB.stl - Motherboard case

This part may be the most difficult to print. Have you ever seen a standard Ender 3 flexible bed pull up at the corners and eventually be pushed aside on a large build like this? I have! My first big build for this project used a fairly new standard Ender flexible magnetic bed. And I found the magnetic bed with the start of the build stuck to it dumped in front of the printer after printing overnight. It pulled up severely at all 4 corners. Of course, after that happened, the rest is just angel hair pasta. I worked through several prototypes to get this final offering that, I hope, prints well for you.

I saved a bit of time by pushing the layer thickness to 0.24 mm instead of the more standard 0.2 mm with a 0.4 mm nozzle. The first layer is kept at 0.3 mm for all my builds. Support is required, and if you push it to 70 degrees, the rivet holes will remain free of supports, which I like since it reduces post processing of the print. The rivet holes in vertical surfaces are actually octagons so the angle is 67.5 degrees at the top of each hole. The primary areas for support are the fan opening and other rectangular openings in the case at 90 degrees.

• 195.8 x 195 x 154 mm print volume 284 g, 29 hr
• 20% infill , 70 degree support , 0.24 mm layers after .3 mm first layer

mITX_PS.stl - Power Supply

The mITX_PS is the base of the system and holds a standard ATX12v power supply. I suppose you could put a smaller SFF style power supply in, but that might be a nice option for future remake or extension to make this little NUT Shell a bit smaller. The layout allows for mounting the unit with it's intake fan pulling from inside the case or from the bottom of the case.

I decided to use a silk lining inside the mITX_PS piece to hide the sides of the power supply because it was a nice color and appearance. In Step 7: Assemble mITX_PS, I show how I put that bit together. Alternately, you may opt to install a bare power supply in which case you need to use mITX_PS1 to replace the cardboard I use in this build. This is a simple rectangular piece that is 1.05 mm thick to raise the power supply to the proper height to match the mounting holes.

• 194.2 x 159.2 x 120 mm print volume, 170 g, 12.5 hr
• 20% infill, 70 degree support, 0.24 mm layers after 0.3 mm first layer

mITX_DB.stl - Drive Bay

The drive bay holds the power switch and USB panel in this prototype build. It can also accommodate two 2.5" drives that are mounted to the top inside of the case. A few extra holes are thrown in to attach things later. I setup this configuration with the top panel to show the full build as originally posted. I anticipate developing alternate items for this top hat position.

The drive bay has the same cross section as the power supply case, since they both mate to opposite ends of the motherboard case. Both parts were developed from the same parent objects.

• 194.2 x 159.2 x 50 mm print volume, 155 gm PLA, 12 hr print time
• 20% infill, 70 degree support, 0.2 mm layers after 0.3 mm first layer

mITX_SP.stl - Side Panel

The side panel is designed to accommodate an air intake over the location of the CPU fan by utilizing an air intake plate. It centers a 120 mm fan layout over the motherboard. The side panel is a way to interface a custom air duct to this system. I used a hole spacing of 105 mm to mate the required air intake to this piece. See the mITX_AI listed next.

• 185 x 195 x 14 mm print volume, 39 gm PLA+ ,3.5 hr,
• 20% infill, no support, 0.2 mm layers, 0.3 mm first layer
• the side panel allows for attaching an mITX_AI air intake

mITX_SP2.stl - revision of the side panel to attach to mITX_MB at the top

I modified the 'top edge' to attach this to the mITX_MB at the top, previously only the sides were attached. The original mITX_SP was designed with the prototype MB piece which was open at the top, like at the bottom power supply.

• 193 x 185 x 14 mm print volume, 44 gm PLA, 5 hr on the Ender 3
• 20% infill, no support, 0.2 mm layers, 0.3 mm first layer
• this modified side panel fixes an overlap problem at the top and provides additional

mITX_AI.stl - Air Intake, Intel socket 1200 with stock i5 fan

This side of the case really sucks, air that is. And if you are using a different motherboard, this piece may not match your CPU heat sink fan location!! I plan to continue this Instructable as a living document for the next trip around the sun called 2021. As part of that, I can help with customization of the air intake for different boards. The naming of mITX_AI files will evolve as I develop additional air intakes for the NUT Case.

The opening can accommodate a 120 mm fan so if you really want to push air, go for it. See the assembly of the motherboard case fan if you go with this option. It is the same in this location, but the hardware that came with the fan works fine here too. You will notice my second board is AMD based and I used the 120 mm fan to replace the 90 mm fan that came with the stock cooler. See the next file.

There are two pieces in this print. The smaller part is a CPU fan ring to help interface the air intake to the CPU fan. This helps to force the air flow through the CPU heat sink and improves cooling efficiency. I used a blue silk PLA to get a metallic look on the intake, even though it is hidden behind some lacy fabric.

• 145 x 145 x 80 mm print volume, 67 gm PLA, 4 hr 15 min
• 20% infill, no supports, 0.2 mm layers, 0.3 mm first layer

mITX_AI-WraithPrism.stl - Air intake, AM4 socket with Wraith Prism cooler

My second Mini-ITX motherboard is an ASUS B550i that has an AM4 socket. The CPU came with the Wraith Prism cooler, so I adapted the NUT Case to provide superior cooling for this combination. The stock fan is 90 mm and was in the way! I decided it was easier to use the fan opening I designed into the side panel to provide cooling air to the CPU cooler.

I was working on AMD air intakes and making the side plate able to slide the fan a around a little to adjust for different motherboards. After fixing a 140 mm fan to the Wraith Prism cooler, I am going back to look at the original Intel air intake to fit the adjustable side panel opening and 140 mm fan. Perhaps this project will find new life in a home that actually has a supportive community for something more than arty wood carving.

Files to print this project have been moved to a site that better supports 3d printed projects.

Overview

Pin rivets are used throughout the NUT Case. In addition to retaining decorative pieces, pin rivets can be used to hold the entire case together. I would recommend using at least twelve sets and up to 30 sets of 4mm steel hardware (nuts and bolts) to hold the case together if you plan on traveling with the NUT Case on a regular basis, but the pin rivets are great if it's just sitting there or only traveling to another room in the house.

Each PRxy-z-y.stl file contains 18 sets of pin rivets. You will need lots and lots of these, so, load up a build plate with as many sets as you like. Print these in multiple colors to mix and match pins and rivets for various looks. Sometimes the pin or rivet breaks when removing but they are cheap little parts so keep some on hand. The tools I used include a bent punch, tooth picks (square plastic picks to clear rivet holes), tweezers (offset is nice), a nail file (smooths down the pin shaft), 1.75 mm filament, pliers (again, offset is more useful) and diagonal cutters, for quick disassembly.

I encountered some variation in diameter of the pins when printed with various filaments. Also, the heads are small and sometimes they can dislodge from the build surface when printing. For this reason I don't recommend combining these on bigger pieces, like dropping a set in the middle of a mITX_PS print. I've had about 1 in 4 failures with printing pin rivets because of the rounded edges at the build surface. It won't be long and I will post rivet only and pin only files. Some of the print failures were with washers printed along with a set of pin rivets.

Washers are provided in four sizes; two diameters, 10 and 20 mm, and two thicknesses, 1 and 2 mm. The naming convention for washers is Wxyzz.stl. The x represents the diameter of the hole, y represents the thickness as a single digit and the zz represents the diameter as a two digit number. A W5110.stl washer is 1 mm thick and 10 mm diameter. These washers have an inner diameter of 5 mm to match the rivets. I used washers inside the case to hold the SWusb part because the USB plugs are tight and could cause the USB ports to pop loose when pulling the cable back out. The washers are a little smaller than some of the holes for mounting pieces and should be a bit tighter at holding SWx items to the case. I'm also considering glue on that particular piece.

Sizes

I needed a method the keep track of the various sizes of pin rivets that may be used in the NUT Shell. I'm using PRxy-z-w where w, x, y and z represent various dimensions in the rivet and associated pin. Pins are designed to match the height of the rivets in each file. I'm using empty Altoids cans to keep these organized by size.

Using the file name form of PRxy-z-w.stl, the following correspondences are observed;

• x - Rivet diameter (fits hole size x mm)
• y - Rivet length, total thickness of material bound
• z - Rivet head diameter
• w - Pin head diameter

For instance, the standard PR54-10-7.stl file has eighteen pins and rivets. The rivets are made for a 5 mm diameter hole and material thickness of 4 mm. The diameter of the rivet head is 10 mm and the diameter of the pin head is 7 mm. This size is used for major assembly of the case and attaching standard parts. I leave open the possibility for different size river and pin heads.

Using Pin Rivets in Your NUT Case

As stated above, the standard 4 mm long pin rivet is used for most of the case assembly since the outer walls are 2 mm thick and the interior mounting holes are about 1.9 mm thick. There may be places where you wish to attach a 1 mm thick decoration directly to the 2 mm case. You would need a 3 mm thick rivet. If you stack decorative items on case rivets, you may need longer rivets. Rivet sizes start at 3 mm and increase in 1 mm increments to 6 mm. The 5 mm long rivets can be used with two wall thicknesses and one 1 mm thick decorative piece, like the daisies I attached to the prototype NUT Case shown. Just add up the thicknesses, or use trial and error.

Decorative items may be placed with any pin rivet location, but specific holes are provided on the mITX_MB bottom and mTX_DB top. These holes are arranged in a 100 mm x 100 mm square, centered, and accept the same pin rivets as the rest of the box. Choose a size that fits the thickness of items that you attach. I will expand on some ideas for decorative side pieces as this Instructable develops over time. I will setup an associated post on Thingiverse when I get this Instructable settled in to further develop this case and decorative elements.

Alternate Pins

The holes in the rivets are about 1.75 mm diameter, perfect for securing with a short length of filament rather than a printed pin. I found that toothpicks can work as well, just be sure to trim them, unless you want a spiky look. Yikes. The plastic picks shown are good to clear the hole in the rivet if it is tight. I push one into the head end of the rivet and twist to remove roughness. Another possibility is to use 14 ga hobby wire as a pin which can be bent into any creative shape. The little umbrella toothpicks can be a fun addition on top of a tropical themed case. Use your imagination here. Or just push a bit of filament into the hole and trim it off.

How It Works

Press a rivet in place through two or more items to be joined and set a pin in it to secure the rivet. Simple! The hole size in the rivet allows for the use of 1.75 mm filament to secure the rivet in addition to the printed pins. The pin can be inserted from either side of the rivet. It will hold better with the pin pushed in

The tip of the rivet is thicker than the 5 mm hole it is designed for. So long as there is not a pin stuck in the rivet, the sides can bend a little and the rivet can be pushed in through the holes. After the rivet is set in place and the parts are squeezed together, push a pin into the rivet from either side to secure it in place. It is helpful to push from inside and outside the case to secure the rivet properly. For this reason leave the case fan installation until after everything else is together. The hole for the case fan allows access inside the case which is helpful in setting the rivets that connect major case parts together, the case rivets.

Another technique I used was to insert my offset pliers through a hole near the rivet to hold the inside of the case so I could press the rivet all the way through both pieces before securing it with a pin. If it seems too tight you can trim it a little with a drill, but be careful to leave enough material to catch the rivet. I have been using a #1 Philips screwdriver that seems to have a 5mm diameter shaft so it makes a good test of the hole size.

Here's a run down on the various parts available. Refer to the nice 3D views available to help select the items to really make your NUT Case pop. Or, create your own embellishments. That's really what I'd like to see. What more can you do to extend this little case.

SWx Hole Covers

I made a few power switch mounts, mainly numbered by hole size. i.e. SW7L3.stl is a simple front panel insert with a 7 mm hole and a couple of small 3 mm LED holes. I use one front panel mount for the switch insert and the other for a pair of USB 3.1 ports. You may design your own insert to provide specific I/O for your needs. See Step 3 for more about power switches.

The SWx family of stl files files also contains several opening blanks to simply cover up some of the 20 x 40 mm holes provided for I/O access.

FTx.stl - Foot with height of x (optional)

Print four feet for a vertical or horizontal build. Use FT24 if the supply pulls air from the base. No feet are needed if you pull power supply cooling air from inside the case. But, feet make it a little easier to pickup. The top of mITX_PS case has air intake holes on all sides to supply cooling air in the standard configuration.

There is an option to turn the completed unit on it's side for a horizontal case. The feet can go in any or all of the accessory pin rivet holes on the bottom of the mITX_MB section. Two on the mITX_PS and two on the mITX_MB works well. This will put the air intake facing up! The two feet on the mITX_MB section need to be 2 mm longer than the two on the mITX_PS in the horizontal position due to the wall offset between the two cases.

Check out Step 7: Assemble the mITX_PS to see how the feet attach.

Wxyzz.stl - Washers in various sizes.

Who doesn't need a few more washers floating around. The simplest of designs, your classic 5 mm washer in a selection of sizes. Wxyzz.stl files are sized with x as the inner diameter, y is the height and zz is the outer diameter. I made 1 mm and 2 mm thick washers in 10 mm and 20 mm diameters.

DaZx.stl - The flowers I used in the prototype build

As you can see in the files, DaZ40x4 has four larger 40 mm flowers. DaZ22x9 has nine 22 mm flowers and DaZ20x9 has nine 20 mm flowers. The DaZfield file contains 12 each of the DaZ40, DaZ22 and DaZ20 flowers.

PSin-side.stl - Color plates inside power supply

Use two of these pieces on the sides of the power supply. Print an interior color for the power supply case and attach at the decorative attach points. An interior piece for the front of the power supply case is in the works. It's just a 1 mm thick piece with mounting holes to show a color though the holes.

PSin-front.stl - Color plate in power supply front

For use in the front of the mITX_PS case to provide a background color for the interior.

FN12cover1,2.stl - 120 mm fan cover

The fan cover wraps the front 120 mm fan in whatever color you choose. The opening allows for the use of a standard finger guard or the left handed wind shifter (pinwheel) shown next. The first version is a solid box and may have some warping when printing. The second cover has the standard holes to break up the box and help mitigate any problems due to shrinkage during the build.

FN12x - Left Hand Wind Shifter (Pinwheel) front fan cover

To help with the look, protect fingers and to deflect airflow, the Left Hand Wind Shifter, FN12x, covers the front fan and deflects air to the sides, top and bottom. Try printing with alternating filament colors or a rainbow filament for striking results.

I wanted to just zip up the files for easy download for the user. Instead, this site forces every stl to be listed individually. That gets a bit cumbersome for the dozens of files provided in this project. These files may end up on Thingiverse or another 3D printer focused site.

Overview

I only need a couple of USB ports available on the front of the case so I arranged to stack a couple ports in a case opening, like with the power switch insert. The cable I used is here.

Sequence

1. Using a printed SWusb insert, attach the USB ports by sliding them into the piece.
2. Insert the SWusb insert into the chosen opening on the case and secure with a couple of pin rivets.
3. After the unit is inserted, secure the USB ports with two nylon ties.(It won't fit with ties on first)
4. Attach the other end of the cable to the proper header on your motherboard in Step 6 or Step 8.

Overview

After cleaning up the mITX_MB by removing supports and bumps, your next steps depend on your configuration. If 2.5" drives are installed below the motherboard, you need to work out any decorative side element before installing them. Pin rivets need to go in before the drives to hold the piece to the case like the feet on the mITX_PS section. Oh, that's in the next section. If there are no drives here, the pin rivets can attach in the standard fashion from the exterior of the case and you can skip this.

You also have the option to install two 2.5" drives inside the optional mITX_DB, drive bay section.. If you have 2.5" SSD drives to mount under the motherboard, put them in before attaching the motherboard to the motherboard case. Here I show where they go, but I didn't use 2.5" SSD drives in this build. Short wires, maybe a right angle SATA connector at the motherboard. Let me know how it works if you put drives down here. There is a very short run from the drives to the motherboard SATA ports. But there are no long runs since this thing is so tight.

While most parts of the case use the pin rivet to hold things together. When holding down the motherboard, it is best to use the four standard #6-32 motherboard screws. They will cut their own threads into the plastic standoffs. Also in this section, four 4 mm x 30 mm screws are used to attach the fan to the case. Four 4 mm nuts are press fit into the case to receive the screws.

Since the front fan is used for exhaust, I am working on a system to deflect the air coming out. The fan hanging on the front like that needs some work as it is visually distracting and some fans are even worse colors.

There is an air intake, mITX_AI, that attaches to the case and helps direct air down to the CPU fan. I made this piece in two parts to easily allow customization. Your CPU location and fan situation may vary. Since the fan height is often of concern, you could interrupt the mITX_AI tube before it finishes to get a shorter version. But alignment is critical, so if your CPU has a different position and or fan, a new mITX_AI piece would need to be designed. I used the loft feature in my CAD program to create this air intake.

The mITX_AI/mITX_SP air intake and side panel combination might be better replaced with a single piece for some of the larger CPU coolers on the market. This is certainly an area I will explore further as I work on a NUT Case with a graphics card for my next build in the coming months.

Sequence

1. Press fit fan nuts
   Place the empty mITX_MB case fan-side down on a solid flat clean work surface. Align a 4mm nut in a fan attachment point and press down with a solid flat object and wiggle it side to side until the nut is pressed into place. Repeat with the other three nuts. If it's too tight, you could use a screw and washer on the other side to pull it in or heat it. Always handle hot items with care and proper tools. If you are using 4 mm hardware for case assembly instead of pin rivets, also press 4 mm nuts into all the locations where you plan to use 4 mm hardware.
2. Press fit case nuts (optional)
   In the same manner as used with the fan nuts, press 4 mm nuts into the case attachment locations that you want to use with 4 mm hardware. You may choose to skip this step and assemble the case using pin rivets
3. Install drives (optional)
   Using screws that came with the drives, mount one or two 2.5" drives to the mITX_MB piece of the NUT Shell. There are holes in the bottom of the mITX_MB case for the 2.5" drive screws. Use a power extension to the drive because the space does not allow for a power connector that is in the middle of a connector. Standard SATA data connectors work fine in the cramped space, just not right angle connectors at this end.
4. Mount motherboard
   Using four #6-32 screws that came with the motherboard, mount the motherboard in the mITX_MB case. If there are connections you need to get to near the PCI connector, I found it easier to connect those wires before screwing down the motherboard. In this case, I fed the fan wire into the case and attached it to the motherboard before mounting it. Note the locations of power switch and other I/O headers you are using before mounting the motherboard.
5. Assemble mITX_SP, side panel and mITX_AI, air intake
   I started by gluing a piece of lacy fabric to the air intake opening. Make sure you choose something that doesn't have glitter that flakes off by rubbing it against itself. One of the first fabrics I considered had gold bits that flaked off easily so I continued my search. It also should breather easily.
   I then attached the mITX_AI air intake to the mITX_SP side panel using four PR54 pin rivets. Note the orientation of the air intake on the side panel. I put an arrow to indicate 'up' on the air intake so I install it correctly on the side panel. The arrow needs to be parallel to the vertical connections that hold this piece to the mITX_MB case so it points to the top of the vertical case.
6. Alternate mITX_SP2, side panel and mITX_AI-WraithPrism, air intake
   With the AMD configuration I am using a 120 mm fan on the side panel to replace the stock 90 mm fan. The fan mounts inside the mITX_SP2 side panel and the duct mounts to the fan. It's all held together with 4 mm hardware and 35 mm long screws. The key headers on this motherboard are easily accessable with the air intake in place.
   Make sure the fan pushes air into the case. A screen is in the works to protect your fingers. This one can bite you.
7. Attach side panel to case
   You may use pin rivets or 4 mm hardware to hold the side panel with the air intake to the motherboard case. Align the air intake with the CPU fan or directly to the Wraith Prism cooler. The Intel air intake should already be prepared with a CPU fan ring that prints with the mITX_AI air intake. Note how much your access is restricted to areas of the motherboard when this piece is in place. Last chance to make some connections up there before continuing.

Overview

I like to save the bulky power supply cables until after the front panel, USB and SATA cables are all hooked up to the motherboard. Since it's a semi-modular power supply, you should connect the power cable to your devices as you install them and then plug the cables into the power supply as the pieces are mated.

If the mITX_DB, drive bay is used, it can be attached to the mITX_MB case before hooking up the power supply. Connect things in the order that seems to make sense.

Simply lay the sections next to each other in alignment and finish connecting power from any drives or I/O items to the power supply. After you attach modular power cables to the power supply, put it in the mITX_PS case and secure with four #-32 screws. Finally, plug the power cables into the motherboard. Slide the pieces together and align the rivet holes

Sequence

1. Front Panel wiring
   Connect power to any items in the drive bay or under the motherboard. Then connect the proper connectors to the headers on the motherboard. At any point, you may attach the mITX_DB, drve bay section to the mITX_MB section and route cables around the edges.
2. Main Power
   Attach the main ATX power cable to the motherboard and the auxiliary power as well.
3. Mate the Assemblies
   Attach the mITX_PS section to the mITX_MB section using printed PR54 pin rivets or M4 hardware.

Your NUT Case Mini-ITX case is done.

Every ending is a new beginning, so now you can put your new creation to work. What are your needs? What software will this system be tasked with? Of course, these are questions that should precede the selection of system components! I'm not getting into a discussion here of operating systems. I simply chose Windows 10 pro because it supports all the programs my target user needs.

I noticed when looking at other Mini-ITX Instructables and projects elsewhere that many people setup a system like this with all SATA ports populated for NAS systems. So I made sure you have a place to put some 2.5" drives, although it is tight. Maybe I'll look at a creating a 3.5" drive module later.The standard SATA cable works in either location.

Shine some kindness around where ever you are.