Gas spring for a box lid

A box lid is hinged at the back and lifts up: toy chests, storage benches, blanket boxes, lids on machine covers. A gas spring makes a heavy lid light to open and stops it from falling shut.

The calculator finds the force (F1), length and stroke of standard gas springs for your lid, and where to fix them. The position of the two mounting points matters as much as the force: a few centimetres decide whether the lid opens by itself or falls shut.

Tips

For children's chests, choose "Stay where I leave it" or "Open by itself": the lid should never slam shut.
Mount the springs inside the box, on both sides, so the lid does not twist.
Use "Let go at …°" to see how fast the lid moves if you release it at any angle.