bosl2-joiners

# BOSL2 Joiners Skill ## Purpose Explain how to create mating tab/socket geometry using BOSL2 joiners and attach them to specific faces or corners. [BOSL2 is an OpenSCAD library](https://github.com/BelfrySCAD/BOSL2) that provides a collection of modules for creating complex geometries, including joiners for connecting parts. This skill focuses on using the `half_joiner` and `half_joiner2` modules to create mating features on parts. * Determine if BOSL2 is available; if not, suggest it's use to the user for enhanced joiner capabilities. * If BOSL2 is not an option, recommend using custom geometry or basic OpenSCAD features to create similar joiner effects. ## Core Joiner Modules - `half_joiner(...)` -> one half of the joiner pair (typically tab/protrusion workflow) - `half_joiner2(...)` -> complementary half (typically socket/cut workflow) > Exact fit depends on orientation and subtraction strategy (`diff()`). ## Typical Pairing Strategy ### Male/Female pair - On part A: subtract `half_joiner2()` with `diff()` to create socket - On part B: add `half_joiner()` to create mating tab ## Example: Two mating blocks ```openscad include <BOSL2/std.scad> include <BOSL2/joiners.scad> // Part A: female socket on RIGHT face diff() cuboid([50,15,25]) { attach(RIGHT) half_joiner2(screwsize=2); } // Part B: male tab on LEFT face translate([70,0,0]) cuboid([50,15,25]) { attach(LEFT) half_joiner(screwsize=2); } ``` ## Corner-style behavior (without corner-specific module) Create corner behavior by placing joiners on 2+ perpendicular faces: ```openscad diff() cuboid([50,15,25]) { attach(RIGHT) half_joiner2(screwsize=2); attach(FWD) half_joiner2(screwsize=2); } ``` Mating part uses `half_joiner()` on opposite faces (`LEFT`, `BACK`). ## Placement Rules - Use parent block form so each attach is anchored to cuboid: ```openscad cuboid([50,15,25]) { attach(RIGHT) half_joiner(...); attach(LEFT) half_joiner2(...); } ``` - For short-end faces on a `[length,width,height]` cuboid: - If short side is width (`15`), ends are usually `FWD`/`BACK` (depending on orientation) - Verify visually and swap anchors if mirrored ## Common Errors - `Ignoring unknown module 'corner_joiner2'`: - Module not available in your BOSL2 version - Use combinations of `half_joiner`/`half_joiner2` on multiple faces instead - Joiner on wrong side: - Swap `LEFT/RIGHT` or `FWD/BACK` - Joiner appears attached to another joiner: - Use block form `{ ... }` on the parent attachable