Print-in-place hinge generator
Generate a print-in-place pin hinge (two interleaving leaves + pin)
A knuckle hinge whose two leaves interleave on a shared axis with a captive pin through every knuckle — it prints pre-assembled and articulates with nothing to snap together. The pin can be its own part, capped at each end inside a pocket, or grown into one leaf so the hinge arrives as two parts. Keep the leaf at least as thick as the barrel is wide, or it hangs above the plate. Download a print-ready STL or 3MF.
How the Print-in-place hinge generator works
What you can adjust
- Mount — Flat leaves · On a wall
- Leaf length
- Hinge length
- Thickness
- Knuckles
- Pin Ø
- Barrel Ø
- Pin — Separate · Captured
- Leaves reach the plate
- Print supports
- Print it — Flat · On its axis
- Fit — Tight · Normal · Loose · Custom
- Clearance gap
Hinge settings that print
The generator’s starting values, and why each one is set that way.
| Setting | Start with | Why |
|---|---|---|
| Mount | Flat leaves | A hinge of its own, printed lying down. It opens about 96°; choose On a wall for a lid that folds 180° to close. |
| Thickness | 8 mm | As thick as the barrel, so the leaves start on the bed instead of in mid-air. Thinner leaves need supports. |
| Barrel Ø | 8 mm | Wide enough for the pin’s bore plus a wall each side. |
| Pin Ø | 3 mm | The rod every knuckle turns on. |
| Knuckles | 5 | They alternate between the two leaves along the axis. |
| Pin | Separate | Three parts: the pin is held by a cap at each end and can be reprinted. Captured grows it into one leaf: two parts, nothing to work loose. |
| Fit | Normal: 0.6 mm (0.3 mm each side) | Enough to break free on most FDM printers. |
| Print it | Flat | The stronger part: the load that pulls it apart runs along the layers. On its axis prints cleaner but puts that load across the layer lines. |
| Leaves reach the plate | On | Carries each leaf down to the bed so it does not print floating. |
Printing a hinge that moves
- Match the leaf to the barrel. The barrels rest on the bed and the leaves are centred on the axis, so a leaf thinner than the barrel starts in mid-air. With Thickness equal to Barrel Ø it prints with no supports.
- Pick the pin for the job. Separate can be reprinted if it breaks. Captured suits a small hinge, one that is opened often, or a plate you do not want a third part on.
- For a lid, use On a wall. Print the box and the lid side by side, open side up, back walls facing. Set Leaf length to half the box’s height plus half the lid’s, and the hinge folds 180° to close.
- If it fuses, give it more clearance. Two surfaces printed in the same pass closer than about 0.15 mm can weld together. Try Fit → Loose, or measure your printer with the tolerance test and use Custom.
Hinge questions
How do you design a print-in-place hinge?
Knuckles alternate between two leaves on a shared pin, with clearance between the pin and its bore and between neighbouring knuckles, so it prints assembled and turns. This generator lays it out for you; with leaves as thick as the barrel, it needs no supports.
What clearance does a print-in-place hinge need?
Normal is 0.6 mm in total, 0.3 mm each side. Do not go below about 0.15 mm between surfaces printed together. For your own printer, measure the clearance with the tolerance test.
How far does it open?
With Flat leaves it stops at about 96°, because each leaf is centred on the axis. On a wall, it folds 180°, enough to close a lid onto its box.
Pin hinge or living hinge?
A living hinge is one thin web that bends: a single part, for clips and folding boxes. A pin hinge turns on a pin, for anything that swings often or carries weight.