Gridfinity guide
Fitting a drawer with Gridfinity
Measuring a drawer, the space the grid leaves, how tall the bins may be, how a split plate joins, and how bins stack.
Measure the drawer
Measure the inside of the drawer, not the opening: the opening is usually larger, and a plate sized to it will not go in. Drawers are seldom square, so measure the width at the front, the middle and the back and keep the smallest number; the same for the depth. Take 1 to 2 mm off each so the plate slides in instead of being forced.
Inches work too. Type a fraction as a decimal (12⅛ in is 12.125 in); the grid is metric underneath, so the plan and the files are in millimetres and the summary shows both.
What to do with the space left over
A cell is 42 mm, so a drawer almost never holds a whole number of them. A 306 mm drawer holds seven cells, 294 mm, with 12 mm to spare. What the plate does with that space is a choice:
- Under about 15 mmLet it be a solid margin around the grid. The plate cannot shift, and a border stiffens the edge.
- 15 to 30 mmPut it on one side as a single strip instead of splitting it: one 25 mm strip at the back holds pens and rulers, two 12 mm strips hold nothing.
- From 21 mmA column or a row of half cells fits. Half cells take half-size bins only, with no magnet or screw holes; the rest becomes margin.
- Over 30 mmMeasure again first: you may be one cell off. If it is real, consider leaving that part of the drawer open for tall things rather than filling it with plate.
The grid need not be centred. Pushing it to the back and keeping the slack at the front, where the hand goes in, is often the practical choice. See drawer sizes to cells for the common sizes.
How tall the bins may be
Bin heights come in units of 7 mm, and the first unit is mostly spent on the bin's own foot and floor, about 6 mm of it. A one-unit bin holds a millimetre; a two-unit bin holds 8 mm.
| Units | Height | Holds inside |
|---|---|---|
| 1 | 7 mm | 1 mm |
| 2 | 14 mm | 8 mm |
| 3 | 21 mm | 15 mm |
| 4 | 28 mm | 22 mm |
| 5 | 35 mm | 29 mm |
| 6 | 42 mm | 36 mm |
In a drawer the stack has to close: the baseplate (4.25 mm, not counted in units) plus 7 mm per unit of bins plus the stacking lip of the top bin (about 4 mm) must stay under the usable height, measured from the drawer's floor to the underside of whatever is above it. An 84 mm drawer leaves room for 10 units in total: one deep layer, or two layers of five, or three of four, three and three. The bins page runs this check and warns when a stack overshoots.
Joining a split plate
A plate larger than the printer's bed is cut into pieces along the grid lines; the seam runs through the wall between two cells, where bins already leave a gap, so a bin bridges it and hides it. The pieces join in one of these ways:
| Joint | What it is |
|---|---|
| Dovetail tabs | Printed onto the piece. In the floor: 8 mm wide at the seam, 11 mm at the end, 1.9 mm into the neighbour, one per cell. In the wall: 1.7 mm at the seam, 2.4 mm at the end, 3.5 mm into the neighbour, where a grid line meets the seam, so the wall between two sockets holds it. The corners are rounded so the tab drops in from a 0.4 mm nozzle without filing. No loose parts. The tabbed piece goes down first; the neighbour is lowered onto it from above, never slid, because the buried end is wider than the mouth. |
| Puzzle tabs | Printed on too, with a 6 mm neck and a 9.2 mm lobe: the strongest joint that lies in the plane of the plate. It needs a solid floor to sit in, which costs filament. |
| Bowtie keys | Loose keys of 14 × 8 mm, narrow in the middle, so a key cannot slide out either way. Half a pocket in each piece. |
| Puzzle keys | Loose keys of 14 × 8.39 mm with a lobe at each end, in half pockets. |
| Snap clips | Loose keys of 14 × 8 mm with a spring in them: they compress on the way into the pocket and hold themselves there. |
| H-clips | Small clips of 3.6 × 3.8 mm pressed in from above once the plate lies in the drawer, for a drawer an assembled plate cannot be lowered into. |
| None | The pieces lie side by side; the drawer's walls hold them. |
Loose keys sit in a solid floor under the sockets, the strongest, or inside the grid walls, which needs no extra filament. A key goes in from below (the pieces are assembled face down and the plate turned over) or from above (the pieces lie in the drawer and a key drops into each junction), which is the way for a deep drawer or one with a lip.
The page on splitting has the cells per printer and where to put the cuts.
Stacking bins
A bin's lip is the same shape as a baseplate's socket, so bins stack on each other as they stand on a plate. Two rules keep a stack standing: a bin needs support at two opposite edges, since one held on one side of its middle tips over; and a small bin must not stand inside a larger bin's footprint, because the middle of a bin is open and the small one drops through. Span the lower bin across its width or its depth and let the upper one rest on its rails.
Questions that come up
- Is the seam visible?It falls in the wall between cells, under the gap the bins leave; with bins in place it is gone.
- Is a split plate weaker?Hardly, in a drawer: the plate lies on a flat floor and is held by the walls, so it never bends. A staggered split takes away the one weakness, a seam the full width that could fold like a hinge.
- Different colours?Every piece is its own file; print each in what you like. Staggered seams make a mix look intended.
- Do I need magnets?Not in a drawer. Magnets matter for a plate that is carried or hangs on a wall, and they force a solid floor.
- My drawer is not a rectangleSize the plate to the largest rectangle that fits, or set the margins per side; other outlines are not made.
- Does it fit plates from elsewhere?Everything follows the published specification: a 42 mm pitch and 41.5 mm bins. Thick, padded plates that do not follow it are not interchangeable.
- How much filament is a drawer?A lot: a 7 × 9 drawer with four-unit bins is over half a kilogram and days of printing. The bins page estimates the material at your slicer's infill.
- Solid or skeleton?A skeleton plate is hollowed under the sockets and keeps the rim and the walls: lighter and faster. Cells with a joint stay solid, and a plate with magnets or screws is solid.
- Where to start?Print one bin and set it on one plate before printing a drawer's worth; that confirms the fit on your printer.