This design is functionally a couple years old now, which means it has been well tested in actual use. There are a few fun-looking garlic-shaped garlic containers available to 3D print that I looked at and was inspired by, but none of them were quite to my standards, which were: 1) quick print time, 2) well ventilated, and 3) big enough to hold multiple bulbs. This version prints in vase mode in two parts, using a couple tricks to have plenty of ventilation holes and gaps, and can hold 4-6 regular bulbs of garlic, depending on bulb size.

When printed with a fairly opaque filament and with an open top, and kept in a place where it doesn't get a lot of direct overhead light, this container does a decent job of keeping garlic both from growing and from rotting. A few times I've opened it after longer stints of not cooking to find that some or all of the garlic inside has dried out without moldering, which in my opinion is the best case scenario if you're likely to forget about garlic for a long while.

The top sort of pops/lightly snaps onto and back off of the bottom, although be aware that it's usually not secure enough to lift the whole thing by the top, especially with garlic inside.

If you're going to keep this somewhere that does get a lot of overhead light, you might try printing the top upside down, with bottom layers included in order to have a closed top. The top is far from the only ventilation, but I haven't actually tested printing or using a closed version. Please let me know if you do!

I designed this to be printed with a 0.8mm nozzle or larger, and with PETG. I have found it to work with PLA with a 0.8mm nozzle, with a firmer fit on the lid. Any smaller definitely will not work with PLA. This can work with PETG and a 0.4 or 0.6mm nozzle, but you will need to be able to print the PETG with a higher temperature, around 270º C. (If you're working with a Bowden setup and your PTFE tube goes directly to the hot end, you don't want to go above 250º C because you will damage the PTFE and get toxic fumes. Which is unfortunate, because adding that extra 20º really makes a big difference in how strong the PETG print turns out.) With thinner walls, you will also want to be sure to choose a very opaque color.

There are a couple variations on the lid to allow for fit flexibility: the default has an offset of 0.8mm for fitting when printed with a 0.8mm nozzle (and works with line width set to 0.9mm). There is also a version with a 0.5mm offset for smaller nozzles, and one with a 1mm offset.

How to print:

• With PLA: 0.8mm nozzle or larger
  • a normal amount of fan
• With PETG: 0.8mm nozzle or larger still recommended, or smaller nozzle size with the requirement of higher temperature
  • You're going to want zero to minimal fan for most of the print, but for the bottom piece, you're not going to want the fan off entirely because there are bridges and you'll want a bit of fan on those.
  • PETG does better hot, but it also may need to be a bit slower, especially on the bottom layers. Make sure you don't have any of your infill speeds set higher than 40. (Unless you know exactly what you're doing and know how to print 270º PETG really fast. I'm still learning tbh!)
• For the bottom: Print with exactly 1.2mm of bottom layers
• For the top part, you set the bottom layers to 0. No bottom layers. You might want to use glue stick to make sure the thin circle stays stuck to the bed.
  • If you're on a Prusa machine using PrusaSlicer, check your skirt settings and make sure you've only got 1 layer of skirt. More than that will break your flow, since you're starting directly on the spiral path.
  • Alternatively, if you want to try a closed top, you turn the top upside down and leave the bottom layers at default.
• Make sure to choose a filament that will be mostly or entirely opaque at the thickness you're printing it at.
• 35% perimeter-infill overlap recommended

Food safety and 3D printing

There are three factors in the printing process to pay attention to when you're worried about food safety:

1. Nozzle and hot end: Brass and some other nozzles tend to contain a bit of lead. They will also have remnants of whatever other filaments have traveled through them.
2. Material: while PLA and PETG are generally considered safe-ISH, you can never actually assume they are, since there are all sorts of things added to them, particularly whatever is used for color. (Silky PLA is always a PLA blend, usually a mystery blend, and should never be considered food safe-ISH unless stated otherwise.) I say "safe-ish" because filaments are rarely certified for food use, but you may be able to find info stating 'as far as we know everything in this one should be safe if printed appropriately and used a single time' for different colors, as in this Prusa blog post that states various PLA and PETG color additives that are safe, as well as giving more information on food safety with 3D prints.
3. Porosity: both PLA and PETG when printed are going to have little cracks and microscopic openings where bacteria will grow. The way we deal with this sort of imperfection in dining-ware is generally with extended application of boiling water. Neither PLA nor PETG can survive this, which means it's not particularly viable to use a bare 3D print made with either of those materials for repeated direct food contact.

Garlic is one of the few food things I'm comfortable sticking in a 3D printed container, printed with a PETG that has been deemed safe-ish, without extra precautions, because it's got an outer casing and you peel it off and throw that away. (And thus, not direct food contact.) I would absolutely wash the print with soap and lukewarm or cold water before actually using it. You might also want to clean it with alcohol or antibacterial soap, on occasion, depending on your preference.

While this design is Creative Commons - Attribution, I would ask that anyone who wants to sell this to other people take all precautions when doing so, including using a certified food-safe filament and a lead-free nozzle.

New to vase mode or still learning?

• Spiral vase mode takes the outside wall of a solid, continuous model and calculates a continuous single spiraling path to print to the top. Usually this is after a few standard solid layers at the bottom.
• In PrusaSlicer, this is the “Spiral vase” option you can check off in Print Settings > Layers and Perimeters > Vertical shells. It will automatically change several of your settings to be compatible with the mode.
• In Cura slicer: Special Modes > Spiralize Outer Contour
• To get a good vase mode print, you'll want to refine a couple more settings. You want to print slow and steady, and toward the higher end of your filament's temperature range. IMO you should test settings for each filament, as well as for different layer heights, to determine a temperature, extrusion %, and speed (if the speed hasn't been slowed down automatically) to get a nice, clean vase mode print with that filament. With PETG, I've had the best results printing at a higher temperature for strength, and turning the fan off or keeping it as low as possible. Sometimes you will see bumps when printing in PLA, and can fix this by lowering the extrusion rate; if you still get bumps, see below:
  • If you're still getting bumps: especially if you're on a more basic machine like an Ender 3, it may be a matter of computing and RAM, and your printer having tiny moments where it pauses. Fixes include using a faster microSD, being hardwired to the printer if you usually use OctoPrint, or upgrading your firmware (this is what worked for me) with options including arc calculation (marlin 2.0 and on), disallowing the printer from writing to the SD card, and turning off the power failure recovery mode. (The latter is very useful but may cause those little pauses with a big file.)
    • Note that PrusaSlicer cannot generate arc moves in vase mode. There are other slicers that do, however.