Chair Lok: The folding chair fix (IKEA/Parametric)

This is a simple snap-fit clip designed to keep folding chairs from opening themselves up when you try to move or store them. I originally designed this to fix the “floppy” folding mechanism on my IKEA FRODE folding chairs (which are sadly no longer available), but the design is fully parametric so you can adapt it to fit almost any tubular folding chair you have.

How it Works:

The clip snaps over the two legs of a folded chair, locking them at a set distance so gravity doesn’t swing them open while you are carrying them. It features a chamfered opening for easy insertion and an optional “pry tab” that gives you a leverage point to pop the clip off easily.

Parametric Customization:

Since chair leg diameters and spacing vary wildly, I’ve included the Fusion 360 file so you can tweak the fit. The key parameters shown in the screenshot are:

• legTolegDistance:  The distance between the outer surface of the legs at the level of opening you want to lock them.  This was ~51 mm for my IKEA chairs:

  

   

• claspDiameter: The diameter of your chair legs.
• claspHeight: How tall the clip is (25mm is a good default).
• openingAngle: Controls how far the “jaws” wrap around the leg. 110 degrees usually provides a good snap without being too hard to remove.
• pryNubLength: Set this to something like 5mm to add a small tab for easier removal. Set it to 0.2mm (as shown) to effectively hide it if you want a flush look.
• text: Change the embossed text to label your chairs or just remove it.

Recommended Materials

PLA/PLA+: Works fine, as shown here in Bambu basic PLA, but might be a bit stiffer and could crack over time if the fit is very tight.

PETG: Also recommended for its flexibility. It handles the repeated stress of snapping on and off better than PLA.

Printing Notes

•Print standing up on its flat face (as oriented in the file).

•Walls: Use 3-4 walls for stiffness.

Instructions

1.Measure your chair leg diameter and the gap between outer surfaces of the legs when folded.

2.Adjust the parameters in the included Fusion 360 file if the standard size doesn’t fit.

3.Print and snap onto the chair legs to lock in place.