Versatile Magnetic Dice Box & Dice Tray

Padding 
- The box has been designed with EVA padding in mind to minimize rattling noise and damage to contents during travel.
- Self-adhesive glitter EVA crafting foam was chosen simply because it is easy to find and easy to handle. This type of product is usually sold in libraries in the kindergarten supplies section as A4 sheets. The self-adhesive ones are a bit more expensive than the regular ones, but they are well worth the price.
- The glitter-covered version was chosen because it is much more forgiving, concealing scratches and damage much better than the basic foam. This does not make it indestructible, however, and in time it will also get damaged and require replacement. Fortunately, this was also taken into consideration during the design process.
- The thickness of the foam I used is 2mm, so try to find something close to this value.

The Lid
- The box lid is sized so that one or more folded A4 paper sheets can fit inside the closed box. This way you can easily carry your character sheet with you, as long as it is below five A4 sheets.
- As is the case with dice boxes, the lid can also serve as a dice tray. If the magnets are glued accordingly, at least two of the lid’s sides will be attracted at all times to one side of the box, both horizontally and vertically.

The Box 
- The inner dimensions of the horizontal box pockets are 32mm(H) x 34mm(W). After bottom and left-right padding, the dimensions become 30mm(H) x 30mm(W).
- The short horizontal pockets are meant for a standard 7-dice Chessex set, with plenty of room for picking them up even with stubby fingers.
- This specific width for the horizontal pockets (30mm) was chosen so that they can also fit two standard Chessex D6s (~15mm) side by side, in case you need to carry multiples.
- The long horizontal pockets are meant for pencils, erasers, pencil sharpeners, markers, or miscellaneous sets of dice that don't follow standard dimensions or numbers.

- The inner dimensions of the vertical box pockets are 32mm(H) x 40mm(W) x 70mm(L). After bottom and left-right padding, the dimensions become 30mm(H) x 36mm(W) x 66mm(L).
- The vertical pockets are meant for standard 28mm 3D minis, but they can also fit certain 32mm 3D minis. I don't own 3D minis, so I use them for all sorts of miscellaneous stuff that might be useful during a D&D session.
- This specific size was chosen so that the pockets can also fit four standard Chessex D20s (~20mm), with plenty of room for picking them up. The vertical pockets can also fit a standard 7-dice Chessex set, though you're going to struggle a bit to pick them up.

- The chamfer of the box edges is not aesthetic, but functional. In order to keep the magnetic field between the lid and the box strong, the magnets need to be as close as possible when the box is closed. With the current design, the magnets are spaced ~3.5mm apart, with only a 0.5mm clearance. Vacuum becomes a problem with these tolerances, making lid removal difficult. A hole in the bottom of each pocket would have fixed this problem, but I dislike that solution more than the edge chamfer, so I went with the latter.

Slicing
Print Settings:
- Layers and Perimeters → Advanced → External Perimeters First: True (for a more uniform look)
- Layers and Perimeters → Advanced → Seam Position: Random (this will lead to multiple tiny holes that can be easily filled in, rather than a large seam line across the whole print)
- Infill → Bottom Fill Pattern: Hilbert Curve (this will lead to a nicer final result)
- Skirt and Brim → Brim → Brim Width: 8mm (the print is long, and prints over 10 hours tend to warp away from the print bed. MagicGoo usually fixes this, but I avoided using glue so I could get a smooth bottom on my PEI sheet)
- Multiple Extruders → Wipe Tower → Enable: False (you are using two extruders to change colors mid-layer, but you don't need a wipe tower)

Printer Settings (for changing colors mid-layer):
- General → Capabilities → Extruders: 2
- General → Capabilities → Single Extruder Multimaterial: True
- Extruder 2 → Preview → Extruder 2 Color: Choose one

- Make sure the logo is printed with Extruder 2.
- Use at least TWO layers for the lid colors; one layer is not enough.
- Restrict seams to exterior or interior corners.

Printing
- Use the same filament color as the paint color, so that paint scratches remain hidden. If you don't plan on sanding and painting, then you can use any color you want.
- Clean the PEI sheet with water and soap under the sink. This provides better bed adhesion than cleaning with IPA. Avoid using glue of any kind, as it ruins the surface appearance.
- If you have a textured PEI sheet, use it—it will lead to a nicer final result.
- If you have a fancier filament, use it for the accent colors—it will lead to a nicer final result.
- Since the print uses multiple colors, you need to be around the printer for the first 1–2 hours to switch colors when prompted.
- Do a test print of the first two layers to see how the final result will look. Since you're using Hilbert Curve, you may want to Live Adjust Z Height so that the print lines are squashed together, leaving little to no gaps.
- If you don't have a heated room for your printer, you could start the print early in the morning so that the whole thing gets printed at a warmer temperature to avoid warping.
- Print the box first—this way you can learn from your mistakes without them being too visible in the final result. Adjust the settings for the lid if required.

Sanding
- Do not sand the bottom of the lid or the box.
- Fill any holes the print has with cyanoacrylate and sanding dust. Don't aim for flatness—it will be flattened through sanding. If the bump is too big, use a cutter to partially flatten it before sanding.
- The best and easiest way to sand flat prints is on a nice flat working area with a water hose nearby. The tiles on your bathroom floor fit these criteria if you're living in a flat.
- Spray the working area with water. Do the same for the sandpaper (A4 sheets of sandpaper work wonderfully). Water helps keep the sandpaper glued to the working area, while also improving sanding results.
- Start with 80 grit sandpaper, then 120 grit, then 240 grit, and last but not least 360 grit. You could work up to 500 grit, but I find this unnecessary most of the time.
- Sand the sides of the print parallel to print lines. You could also use a figure-8 pattern, as it leads to nice results, but only after you reach 240 grit and above.
- Move the print back and forth against the wet sandpaper with straight, precise, and constant movements, in sets of 16/32. After you've completed a set, switch the side. You want the same number of sets on all sides for a uniform look.
- Don't aim for perfection from the start—you will improve results later.
- After you've completed a set for all sides, rinse the print under the sink, then inspect the results. If they are not uniform, continue sanding with the same grit. Otherwise, advance to the next grit.
- Corners and small flat areas require a different approach while sanding. I personally use a manual sanding handle tool meant for sanding walls. This way I can move the sanding surface against the print rather than the other way around.
- If you've lost patience, complete the set on all sides, then stop sanding. Let the print dry while you go do something else, then come back once it's dried and inspect it for flaws. If you're satisfied with the results, proceed to the next step.

Magnet Arrangement
- Out of all the possible magnet arrangements, this was the most permissive one I could find with this type of magnet, since it allows for at least one of each possible box-lid configuration to attract. In the symmetrical configuration, they repel each other.
- To make all possible configurations work, you could modify the magnet slot and create room for a magnet (spherical or not) to spin:
   - Lid over box → One way they attract, the other they repel.
   - Box inside dice tray (flipped lid) → One way they attract, the other they repel.
   - Dice tray parallel to the box along the long side → Two ways they attract, two ways they repel.
   - Dice tray parallel to the box along the short side → Two ways they attract, two ways they repel.
   - Dice tray perpendicular to the box (one short side/one long side) → Four ways they attract. (This was an unintended side effect, and it is not perfect attraction since only one magnet attracts while the other repels. But since the magnet spacing is not the same, together they force the box and the dice tray into a stable non-symmetric configuration that works surprisingly well.)
- Two sets of dice trays and boxes will be attracted to one another into a stable configuration one way or another.

Gluing Magnets
- When gluing the magnets, follow the drawings provided.
- Print yourself a set of magnet gluing tools to help with this process.
- Use cyanoacrylate glue, but be careful not to overdo it. Use the magnet tools to glue the magnets flat into position.
- If you mess up the magnet orientation, try your best to remove it, even if you break it in pieces. Clean the slot, then re-glue it correctly before continuing.

Painting
- Use a matte paint in a color similar to the filament, so that paint scratches remain hidden.
- Cover the bottom of the box and the dice tray with painter's tape.
- The tape should not go beyond the colored perimeter, so use a cutter to trim any excess.
- Use your fingernails or a credit card to ensure the tape is firmly stuck along all edges before painting.
- Painting should be done in a well-ventilated area, or while wearing an N95 breathing mask.
- Place the print above the ground while painting. You can use the cap of the spray paint or something else that is flat and smaller than the box. Basically, you want the print to hover while you're painting.
- Spray the paint in short bursts while moving around the part. You could also improvise a turntable and spin it carefully while spraying.
- Do not aim for full coverage from the start! Do not overdo it with paint — it will form drips. There is no way to speed up this process, so don't try to cut corners or else you'll have to sand the paint away and redo the whole thing.
- Let the paint dry for 2–4 hours. Inspect the results, sand again if necessary, rinse and clean off any dust, let it dry, then apply another thin coat of paint. Once you've applied three coats, the painting process should be complete.
- This step is optional, but if you want, you could also varnish the print. Varnish usually helps with paint scratches, but it is not required if your paint matches the filament color. If you do use varnish, make sure it matches the glossy/matte finish of the paint.

Box Padding
- Print the provided templates and use them to cut the EVA foam into shapes more easily.
- For each pocket, glue the EVA foam in the following order: Bottom (1st) → Horizontal Walls (2nd) → Vertical Walls (3rd).
- Only the final pieces of EVA foam need to be perfectly aligned — the rest will be covered and don’t require precision.
- Use the 3D-printed templates as tools to push the foam into corners and press it flat against the walls.

Box Cover
- Do this part in a quiet workspace, preferably on a table while sitting on a chair. You will need steady hands and precision tools like toothpicks or sewing needles.
- To do this safely, you will need cyanoacrylate gel, not liquid. Even then, use the tiniest amount possible. Do not overdo it, as it will ruin all the work you've done so far.
- Apply tiny drops of gel with a toothpick or sewing needle — start with all the corners, then the wall intersections, then along the long walls.
- Place the Box Cover on top and gently press it into position, allowing any excess glue to flow into gaps rather than spill over the edge.
- This should be more than enough to firmly secure the Box Cover. If you find a loose spot, use a sewing needle to insert a bit of gel underneath at that location.

Lid Padding
- Glue the bottom EVA foam in place, and use one of the 3D-printed templates to press it flat against the lid without leaving marks.
- Cut the EVA foam for the walls, then glue it in on the respective covers starting from a top corner. The adhesive is fairly forgiving, so if you make a mistake, you can backtrack and redo that section.
- Glueing the covers to the lid can be done using cyanoacrylate gel or double-sided tape. I recommend double-sided tape, as it allows for easier replacement of the EVA foam if it becomes severely damaged. If you use glue, be careful not to overdo it — excess glue will overflow and ruin the work you have done so far.

- Done! Enjoy your Versatile Magnetic Dice Box & Dice Tray!

Disclaimer: The general layout of this model was inspired by the “Perfect Magnetic Dice Box and Rolling Tray” by user @Maladaptive. However, all other aspects of the design are original, and as such, this model is not a remix of the original work.