openGrid - Self-Expanding Snap

2026-01-17 Update: openConnect is now the recommended option. While you can still choose to use MultiConnect connectors, openConnect offers several distinct advantages. See the model page here for details.

An open-source snap for openGrid (Standard and Lite). It's based on David's official openGrid snap, with modifications and an added self-expanding mechanism. When the connector is completely screwed in, the snap expands by more than 1mm, making it quite sturdy.

Snaps provided in .3mf files have the default expansion distance, tested on Bambu PLA Basic, Bambu PETG HF, and Sunlu PLA+ 2.0. If you find the snap too tight or too loose, use the customizer to adjust the expansion distance to suit your filament. Other customizable parameters include snap shape (directional vs. symmetric), snap thickness, spring thickness and more.

For community designers: if you want to include any of my snaps or screws in your print profiles to make it easier for users, please feel free to do so.

You can use coin screwdriver Hex bit to help with installing.

Feel free to use the code, and any suggestions or contributions are welcome. GitHub repository

More details:

The revised Lite snap is 4mm thick, just like the openGrid Lite board. The reason the old version was only 3.4mm thick was to conform to David's official version, which could be installed simultaneously on both sides of the openGrid Standard board (6.8mm thick). Self-expanding snaps are rarely used that way, so only the stronger 4mm version for the Lite board is provided.

The 4mm thick snap and connector have a "4" on the bottom to easily differentiate them from their 3.4mm counterparts. If you don't like the text, you can go to the customizer and turn it off.

2025-11-22 Update: Now the threads have blunt start by default, which should help prevent cross-threading and overtightening. Models with blunt threads have a decorative 'lock' symbol at the bottom. If you prefer the earlier version, you can change 'threads_type' in the customizer.

2025-09-04 Update: 
Added a notch at the bottom for easier uninstalling. With the new openGrid gadgets, consistency has become more important, so default threads offset angle is now set to 0, unchanged from David's original snaps.

2025-08-08 Major Revision:
Model recreated in OpenSCAD. Added support for openGrid Standard. Revamped screw threads generation. Increased thickness of the Lite snap from 3.4mm to 4mm. Improvements in spring geometry etc.