An open-source hook generator for openGrid, using the openConnect system. This model is called the Sturdy Hook because it is designed to be printed on its side, which avoids the common failure point of layer line separation. Use this model with openConnect folded snaps for maximum holding strength.

The recommended minimum width for these hooks is 20 mm. If you need a narrower hook, check out the openGrid Frame-Fit Hook Generator or use "hook_tip_sliceoff_side" to narrow the tip.

Several example .stl files are included, with the parameters used to generate them in the file names.

Customization guide:

1. Set "hook_vertical_grids". The default is 1 for a compact hook; increase it for a taller hook that covers more openGrid tiles.
2. Choose "hook_shape_type". Use the default "Circular" for a smooth curved hook, "Rectangular" for a squared-off hook with an extended tip, or "Flat" for a straight shelf-like geometry.
3. Adjust the hook reach. Use "hook_length".
4. Adjust the hook body. Use "hook_width" and "hook_thickness". Increase "hook_corner_fillet" for a sturdier, thicker inside corner.
5. Tune Circular hook tips. "circular_tip_radius" controls the radius of the tip, "circular_tip_angle" controls the angle of the tip arc, and "circular_tip_thickness_scale" controls whether the hook becomes thinner toward the tip.
6. Tune Rectangular hook tips. "rectangular_tip_extra_length" extends the hook tip.
7. Optional: narrow the hook tip. Use "hook_tip_sliceoff_side" to choose which side is cut, and "hook_tip_sliceoff_target_width" to control the hook tip width after the cut. This allows the hook to fit objects with small holes.
8. Optional: add a bottom truss. Use "truss_vertical_grids". This helps the hook handle heavier loads. Adjust "truss_thickness", "truss_rounding", and "truss_max_angle" if you want to tune the truss shape.
9. Optional: set miscellaneous options:
   • "hook_side_rounding" and "hook_tip_rounding" - adjust rounding on the hook body and tip.
   • "use_custom_height" and "custom_hook_height" - enable these if you do not want the hook height to be an exact multiple of the openGrid tile height (28 mm).
   • "slot_lock_distribution" - add more openConnect slot locks for a tighter mount, or fewer locks for easier installation.
   • "slot_entryramp_flip" - change the openConnect slot entry ramp direction, which can matter when installing in tight spaces.

The model is open-source under the CC-BY-SA license. Like all the OpenSCAD models I've designed for openGrid, it can be found in this GitHub repository. Feel free to use the code; feedback and suggestions are welcome.

2026-06-21 Update: Added optional "hook_tip_sliceoff_side" to make the hook tip narrower. Idea by @3DBIG.

2026-04-06 Update: Added an optional bottom truss. Added "hook_shape_type" with "Circular", "Rectangular", and "Flat" options. Some parameters were also adjusted to make the customizer easier to use.