How tethers fail.
Knot slip. Cord abrasion. UV degradation. Foot detachment. What to look for and how to fix it.
Knot slip (most common)
Symptom: the bowline at the caddy end gradually opens up. Cause: cord material is too slick (nylon paracord, silicone). Fix: switch to braided polyester. Re-tie quarterly.
Cord abrasion (second most common)
Symptom: the cord frays where it passes through the tee's loop. Cause: the loop edge has a sharp 3D-printed corner. Fix: rotate the cord 180° at the loop to expose unworn cord. If the fray is bad, cut and re-knot.
UV degradation
Polyester slowly weakens under direct sunlight. For an indoor simulator this is irrelevant. For range use, expect cord life of about a year before it visibly chalks. Replacement cords are cents.
Foot detachment
Rare. Symptom: the printed splay foot tears off at the root. Cause: a strike directly on the foot (skulled iron). Fix: print a replacement; the v1.scad file is open and editable.