I’ve been trying out a variety of techniques, and what works best for one knot may not be best for another. A bit of lateral thinking often helps (e.g. did you realise that a shoelace bow is actually a reef knot with one of the loose ends of each cord passed back through the existing loop?) , and a willingness to completely scrap one idea and start again from scratch (and to do that many times over!) is essential. Working with a low res model makes the starting all over again bit much, much easier!
These are the bases for the current models:
- For the bowline I’m still going with the cut-down output of the KnotTyer3D-generated OBJ (from the built-in Bowline.kt3 model). But I may still scrap it and start again from scratch!
- The double-cord thumbknot and trefoil were created by extruding a double/single 8-vertex circle and manually positioning/orienting each extrusion.
- The single-cord thumbknot was created by deleting one cord from the double-cord version and iteratively adjusting each circular edge loop in turn until it was tight again.
- The reef knot started as an eight sided torus with one circular edge loop ripped and extruded to give the two ends.
- For the shoelace bow (and after many false starts) I went with three cylinders poking through a torus as a starting point!
One thing common to all the knots is that once the basic shape is set up it’s an iterative process to tighten up the knot and fine tune the shape. I’m finding that I usually view the knot from all angles, pick the circular edge loop that looks worst, and adjust it’s position and rotation (about whatever axes are necessary) until it looks ‘better’. Then look again, pick the worst loop again (hopefully a different one!), etc.
Note: for all the current knots I’m deliberately modelling the whole cord. For many purposes this will probably be overkill (e.g. a shoelace bow will usually be tight up against the shoe, so the half-knot on the underside is unnecessary). So even simpler versions of the knots are possible, and perhaps even more useful.