What a 3x1 is for
The reason to print one bin across three cells is length. Inside, this tray is 122.3 mm long and 38.3 mm wide, which takes things no square bin will: a set of hex keys, needle files, pencils cut to length, a 100 mm steel rule, cable ties, a glue stick lying down. Leave it as one compartment for those. If you want three small pockets in a row instead, set the compartments across to 3 and each becomes about 40 by 38 mm, but three 1x1 bins do that job with more freedom to rearrange.
What to measure
Measure the longest item that has to lie flat and compare it with the 122.3 mm inside length; an item up to about 128 mm still fits on the diagonal. Then measure the height you have. This page uses 35 mm, five of the usual 7 mm steps, which leaves 29 mm of depth after the 4.75 mm feet and the 1.2 mm floor. A low tray like this lets you see and pinch small tools; raise it only if the contents would spill.
Clearance, wall and material
The clearance to the grid is 0.5 mm, taken off once, so the bin is 125.5 mm where three cells are 126 mm. The outer wall is 1.6 mm, thicker than on the smaller bins of this site: a long wall with no divider to brace it has only its own stiffness, and at 1.2 mm a 125 mm side tends to bow when the tray is gripped in the middle. PLA is stiffer than PETG and is the better choice for a long open tray. The bin has three plain square feet, 35.6 mm each, and no stacking lip.
Printing
Print feet down, with the long side along whichever axis of your printer moves the bed least, to limit ringing on the long walls. The floor bridges two 6.4 mm channels between the feet without support. Four lines of a 0.4 mm nozzle make the 1.6 mm wall, so set two perimeters or more and the wall has no infill.
Outline drawing
Top view, to scale. Three cells of the 42 mm grid, less 0.5 mm clearance.
Parameters the generator will use
| Setting | Link parameter | Value |
|---|---|---|
| Model | model | grid_bin |
| Grid cells across (X) | units_x | 3 |
| Grid cells deep (Y) | units_y | 1 |
| Total height (Z) | height | 35 |
| Outer wall thickness | wall | 1.6 |
| Floor thickness above the feet | floor | 1.2 |
| Compartments across (X) | cols | 1 |
| Compartments deep (Y) | rows | 1 |
| Divider thickness | divider | 1.2 |
| Clearance to the grid | fit_clearance | 0.5 |
| Foot height | foot_height | 4.75 |
| Foot inset | foot_inset | 2.95 |
All lengths are in millimetres. Outer size from these values: 125.5 x 41.5 x 35 mm.
Open the generator with these values
This model needs the $7 licence key: one payment, one key, and it opens all five paid models. Get a licence key on Gumroad ($7)
The bin on a 42 mm base grid needs a licence key: without one the generator shows the model locked, lists the values from this link and fills them in as soon as you unlock. The fitted drawer organiser bin is the free model and downloads with no key.