Spool for leaders and mackerel rigs
A flat spool with a soft TPU hook park, so a five-hook rig can be put away wet and come out without a tangle.
The problem
A mackerel rig is five hooks and two metres of fluorocarbon. Put it straight in the box and it is a knot next time. Most people use a scrap of foam and a rubber band, and then the hooks sit there rusting into the foam.
The fix
The core is 70 mm across. Go under that and fluorocarbon takes a permanent set, which defeats the point of coiling it neatly at all. Along one edge sits a strip of TPU 95A with a slot for each hook, so the points stand clear instead of burying themselves in the plastic. The spool body is PETG, with 0.3 mm of clearance between spools when they stack, so they still come apart with wet hands.
The base is open with drainage slots. It is standing salt water that ruins hooks, not the water itself. The prototype has lived in the box through a season of mackerel and coalfish. The next revision gets deeper hook slots, because the smallest hooks dropped out when the box went over on its side.
More ideas
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Name, phone number and registration embossed into the tag itself — not written in marker that vanishes in three weeks.