Living hinge generator

Generate a laser-cut living hinge: straight, wave, diamond, cross, honeycomb or auxetic pattern, sized to your panel, slit length, bridge and spacing. Free SVG download, nothing uploaded.

A living hinge turns a flat sheet into a curve by cutting a field of slits through it. Pick one of six real-world patterns, set the panel, the cut size, how much material stays between cuts and how close the columns are, and download the pattern ready to cut.

The six patterns

• Straight slits. The classic lattice: parallel slits in a brick-wall offset. The most reliable hinge and the one shops use in products; bends tightest for a given spacing.
• Wave slits. Sine-wave slits in the same brick offset. Flexes like the straight lattice with a softer look, and the curved strips are less prone to splitting along the grain.
• Diamond (zigzag) slits. Zigzag slits whose neighbours run in anti-phase, so the strips between them form a chain of diamonds. Flexible and decorative; suits the outside of a box or lamp.
• Cross (plus cuts). Plus-shaped cuts on a staggered grid. One of the most flexible patterns and it bends in two directions on thin material; the material between the arms works as short springs.
• Honeycomb. Hexagonal cells of material joined to their neighbours at the corners, every cell wall cut. Flexes on both axes and holds a compound curve; the pattern on lamp shades and speaker fronts.
• Auxetic (rotating squares). A checkerboard of horizontal and vertical slits that leaves squares pivoting on thin ligaments. Bends and stretches in two directions for gentle compound curves; less forgiving than straight slits, test first.

Choosing the numbers

Three numbers set how a slit hinge behaves. Slit length: longer slits leave longer unsupported strips of wood, which bend more easily. Bridge: the material left between the end of one slit and the start of the next in the same column; less than 1.5 mm snaps in plywood. Column spacing: closer columns mean more, thinner strips and a tighter minimum radius, at the cost of strength and cutting time. For the cell patterns (cross, honeycomb, auxetic) the size is the cell and the bridge is the ligament that joins the cells: 8–12 mm cells with 1.5–2 mm ligaments is the usual range in 3 mm material.

Starting points

• 3 mm birch plywood, gentle curve: straight, slit 30, bridge 2.5, spacing 4.
• 3 mm plywood, tight curve (radius under 30 mm): straight, slit 20, bridge 2, spacing 2.5.
• Plywood that splits along the grain: wave, slit 25, bridge 2, spacing 3.5, swing 1 mm.
• A lamp shade or speaker front that has to hold a compound curve: honeycomb, cell 10, ligament 2.
• A dome or saddle in 2 mm plywood or card: auxetic, square 8, ligament 1.5; cross, size 12, ligament 2.
• 3 mm MDF: it is weaker across the strips, so keep the bridge at 3 mm and spacing at 4 or more; MDF bends once into a fixed curve, so glue it in shape.
• Acrylic: living hinges in acrylic crack cold; warm the hinge with a heat gun before bending and keep the radius gentle.

Testing before the real part

Cut a strip 40 mm wide and 120 mm long with the pattern across the middle, bend it round a tin or a bottle of the radius you need, and listen for cracking. If it splits, lengthen the slits or widen the bridge; if it will not reach the radius, shorten the spacing. Keep the strip: it is the swatch you will match the next job against.

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