Design your own products with Ponoko

This is the lattice hinge test sample as described in http://def-proc.co.uk/b/wghsx

If you want to produce products with this very convenient flexible hinge arrangement, you should be aware of the practical limits to ensure your products are not likely to fail in normal use.

The sample contains 3 sizes of hinge, each with the same 44mm internal radius of curvature (47mm external radius), where each has a different calculated maximum stress at 90 degrees. Also included is a 44mm radius, 90 degree corner shape so the samples can be shown at their intended operating condition.

Samples are also available without the corner: http://www.ponoko.com/design-your-own/products/lattice-hinge-test-2-small-stress-limitation-9088

When cut in 3mm acrylic, the smallest 8mm link will bend to 90 degrees but is fragile if mistreated. The middle size 14mm link will bend further, but may not reach 180 degrees if the sample is cold or excessive bending is performed quickly. The tallest sample (28mm) can be bent comfortably to 180 degrees, but is noticeably less stiff than the other two.

Having an understanding of how these lattice hinges work will allow you to create better products with less failures.