How to Generate Custom Gridfinity Bins with AI
What Is Gridfinity?
Gridfinity is an open-source modular storage system created by Zack Freedman. It consists of standardized baseplates and bins that snap together on a grid, letting you organize tools, electronics, craft supplies, and hardware in drawers and on surfaces.
The system is popular because it is simple, extensible, and 3D-printable. A standard baseplate sits in your drawer. Bins of various sizes and configurations snap onto the baseplate. When your storage needs change, you rearrange the bins.
The problem is finding the exact bin you need. Standard Gridfinity generators give you rectangular bins with basic dividers. But real-world organization demands custom compartments: a slot exactly sized for your calipers, a bin with a label holder angled for visibility, a tall bin for drill bits next to a shallow one for screws.
This is where AI-generated Gridfinity bins shine. Instead of searching through thousands of Thingiverse uploads or fiddling with parametric generators, you describe the bin you need and get geometry that fits the standard.
Gridfinity Standard Dimensions
Before you start prompting, understanding the dimensional standard helps you get better results.
| Dimension | Value | Notes | |-----------|-------|-------| | Grid unit | 42mm x 42mm | The fundamental module. A 1x1 bin occupies one grid cell | | Bin clearance | 41.5mm x 41.5mm | Actual bin footprint (0.5mm clearance per side) | | Grid height unit | 7mm | Standard height increment | | Baseplate height | 5mm | Standard baseplate thickness | | Stacking lip | 2.15mm tall, 0.8mm inset | Allows bins to stack on top of each other | | Bottom profile | Rounded tab, 0.8mm radius | Snaps into baseplate grid | | Wall thickness | 1.2mm typical | Standard for FDM printing | | Corner radius | 3.75mm | Standard rounded corners on bins | | Magnet holes (optional) | 6.5mm dia x 2.4mm deep | For baseplate attachment with 6x2mm magnets |
These dimensions are not arbitrary. The 42mm grid unit comes from optimizing for standard drawer widths. The 7mm height unit keeps bins stackable at predictable increments. The 0.5mm clearance ensures bins slide in and out smoothly without wobble.
When you prompt PrintMakerAI for Gridfinity bins, including these terms signals exactly what you want. The AI knows the standard and will generate compliant geometry.
Your First Custom Gridfinity Bin
Start simple. Here is a prompt that generates a basic bin:
"Generate a Gridfinity bin, 2x1 grid units, 3 height units tall (21mm internal), with two equal compartments divided along the long axis. Include a stacking lip and standard bottom profile."
This gives you a bin that is 84mm x 42mm on the grid, 21mm of usable internal height, split into two compartments. The stacking lip means you can stack another bin on top. The standard bottom profile means it snaps into any Gridfinity baseplate.
That is a useful starting point, but the real power is in customization.
Prompting for Custom Compartment Layouts
Real tools do not fit into equal rectangular compartments. Here is how to describe more complex layouts:
Asymmetric Dividers
"Gridfinity bin, 3x2, 4 height units. Divide it into three sections along the long axis: the left section is 1 grid unit wide, the middle is 1 grid unit wide with a cross-divider splitting it into two rows, and the right section is 1 grid unit wide with no divider."
This produces a bin with five compartments: one tall-and-narrow on the left, two stacked squares in the middle, and one tall-and-narrow on the right. Perfect for storing a combination of long tools and small parts.
Sized for Specific Items
"Gridfinity bin, 2x2, 3 height units. Create a compartment sized for a digital caliper (155mm x 25mm x 15mm) on the left side, and fill the remaining space with two small square compartments for caliper accessories."
When you specify the item dimensions, the AI sizes compartments to fit with appropriate clearance (typically 1-2mm per side).
Angled Dividers
"Gridfinity bin, 3x1, 5 height units. Add a diagonal divider from the front-left corner to the back-right corner, creating two triangular compartments. This is for sorting two types of small parts by dumping them in and letting them slide to each side."
The AI generates angled internal geometry that standard generators cannot produce.
Adding Label Holders
Labels make Gridfinity systems usable long-term. Without labels, you end up lifting every bin to see what is inside.
Front Label Tab
"Gridfinity bin, 2x1, 3 height units, with a label tab on the front face. The tab should be 12mm tall and angled 45 degrees outward from the front wall, wide enough for a 12mm label tape strip."
This creates a small shelf on the front of the bin that holds a label tape strip (like from a Brother P-Touch) at an angle for easy reading.
Recessed Label Slot
"Gridfinity bin, 2x1, 4 height units. Add a recessed label slot on the front face, 36mm wide and 15mm tall, recessed 0.6mm into the front wall. The recess should be sized for a standard adhesive label."
The recessed slot keeps the label flush with the bin surface, preventing it from catching on items as you pull the bin out of a drawer.
Engraved Text
"Gridfinity bin, 1x1, 3 height units, with 'M3 BOLTS' engraved 1mm deep on the front face in a clean sans-serif font, 8mm tall."
Direct engraving eliminates the need for separate labels entirely. The text is part of the model.
Multi-Height and Stepped Bins
Not everything in your drawer is the same height. Gridfinity supports variable-height bins that sit side by side.
Stepped Bin
"Gridfinity bin, 3x1. The left 1x1 section is 2 height units tall. The middle 1x1 section is 4 height units tall. The right 1x1 section is 6 height units tall. Like stair steps ascending from left to right. Each section is its own compartment. All sections share a common bottom with standard Gridfinity base profile."
This creates a staircase bin where shorter items sit in the front (low section) and taller items in the back (high section). When arranged in a drawer, you can see into all three compartments at once.
Tall Bin with Shallow Tray
"Gridfinity bin, 2x2, 6 height units. The main bin is one open compartment. Add a removable shallow tray that sits on the stacking lip, 1 height unit deep, divided into a 2x3 grid of small compartments. The tray lifts out to access the deep bin below."
This is a two-layer bin: a deep lower compartment for large items, with a removable shallow tray on top for small parts. PrintMakerAI generates both pieces with compatible dimensions.
Bins with Functional Features
Beyond simple compartments, Gridfinity bins can include functional geometry that standard generators do not support.
Tool Holders with Shaped Cutouts
"Gridfinity bin, 3x2, 5 height units. Create six hex-shaped holes in a 3x2 grid, each hole 10mm across flats and 30mm deep, sized to hold hex screwdriver bits upright. Leave 3mm wall thickness between holes."
This turns a bin into a dedicated tool holder where each item has its own shaped slot.
Sliding Lid
"Gridfinity bin, 2x1, 3 height units, with a sliding lid. Add rails on the inside of the long walls, 2mm wide and 1.5mm from the top edge. Generate a separate lid piece that slides in from one end on those rails. The lid should be 1.5mm thick."
A sliding lid keeps dust and debris out of bins holding sensitive components like electronics or precision parts.
Drain Holes
"Gridfinity bin, 2x2, 2 height units, with a grid of 3mm drain holes spaced 8mm apart across the bottom. This bin will hold parts that get washed and need to dry."
Drain holes are common for bins holding hardware that gets cleaned in ultrasonic baths or solvent.
Screw-Sized Sorting Bins
"Gridfinity bin, 4x1, 3 height units. Divide it into 8 equal compartments (each about 21mm x 21mm). On the front face of each compartment, add an engraved label: M2, M2.5, M3, M3.5, M4, M5, M6, M8."
This creates a complete metric screw sorting bin in a single prompt. See the gridfinity bin example in the gallery for a similar design.
Print Settings for Gridfinity
Gridfinity bins are straightforward to print, but a few settings matter for fit and function.
| Setting | Recommended Value | Why | |---------|------------------|-----| | Layer height | 0.2mm | Good balance of speed and surface finish | | Wall count | 3 (1.2mm at 0.4mm nozzle) | Matches standard wall thickness | | Bottom layers | 4 | Solid bottom for structural integrity | | Top layers | 4 | Solid top surface for stacking lip | | Infill | 15-20% | Bins do not need high strength | | Infill pattern | Grid or gyroid | Either works well | | Supports | None | Gridfinity bins are designed to be supportless | | Material | PLA or PETG | PLA for most uses, PETG for chemical resistance | | First layer speed | 20mm/s | Good adhesion for the large base footprint |
The standard Gridfinity design is self-supporting. No overhangs exceed 45 degrees, and bridges are short enough to print cleanly. PrintMakerAI enforces these constraints automatically, so the bin you generate will print successfully on the first try.
Advanced: Combining Bins with Baseplates
You can generate both bins and baseplates:
"Generate a Gridfinity baseplate, 4x4 grid, 5mm thick, with magnet holes at each grid intersection (6.5mm diameter, 2.4mm deep). Add screw holes at the four corners for mounting to a drawer bottom."
And then generate bins to fit:
"Generate a set of Gridfinity bins for a soldering station: one 2x2 bin (4 height units) with compartments for a solder spool and flux, one 1x1 bin (6 height units) for a soldering iron rest with a V-groove at the top, and two 1x1 bins (2 height units) for tip storage."
Each piece snaps together on the baseplate. The AI generates all parts to the same standard, so they are compatible without manual adjustment.
Prompting Tips for Gridfinity
Always specify grid units, not millimeters, for the base. Say "2x3 bins" not "84x126mm." The AI maps grid units to the correct millimeter dimensions automatically.
Specify height in height units or millimeters. "3 height units" and "21mm internal height" both work. Height units are clearer for standard increments.
Mention the stacking lip explicitly if you want it. Not all bins need one. If you are making a bin that will never be stacked, skipping the lip gives you a few extra millimeters of internal height.
Describe the bottom profile. "Standard Gridfinity base profile" tells the AI to include the rounded tabs that snap into the baseplate. If you are making a standalone bin (no baseplate), say "flat bottom."
Reference the items you are storing. "Compartment for 18650 batteries" is more useful than "compartment 20mm diameter." The AI knows common component dimensions.
Iterate on compartment layout. Get the basic bin shape right first, then refine:
"That looks good. Make the left compartment 5mm wider and add a small notch in the divider so I can slide flat items between compartments."
Why AI Beats Parametric Generators for Custom Bins
Parametric Gridfinity generators (like those on Printables or built into OpenSCAD) give you a grid of equal compartments with optional dividers. They work for basic bins.
But they break down when you need:
- Asymmetric compartments
- Shaped cutouts for specific tools
- Angled dividers
- Integrated labels
- Multi-height stepped designs
- Sliding lids or other moving parts
- Custom features like drain holes or cable routing
These features require either modifying generated SCAD code (which requires programming knowledge) or modeling from scratch in CAD (which requires CAD knowledge). AI-generated bins handle all of these through natural language.
Describe what you need. Get geometry that fits the standard. Print it.
Building Your System
The best way to start a Gridfinity system is to measure your drawer or surface, decide on a baseplate size, and then generate bins for the items you store most often. Start with a few standard bins and iterate as you discover what compartment sizes and features work for your workflow.
Browse the Gridfinity bin gallery example to see what is possible, then sign up for PrintMakerAI and describe your first custom bin. You will have a print-ready STL in minutes.