Spool
The cylinder the line winds onto. Its size sets line capacity and, on a baitcaster, how easily light lures cast.
On a spinning reel the spool stays still while the rotor wraps line around it, and the drag knob usually sits on top of it. On a baitcaster the spool itself turns during the cast, so its weight is the single biggest factor in whether a light lure will fly at all. A lighter spool takes less energy to start spinning, which is why finesse baitcasters advertise shallow, thin-walled spools.
Fill level matters more than people think. A spinning spool filled to within about an eighth of an inch of the lip casts well; overfill it and it throws loops off the front, underfill it and you lose distance to friction against the rim.
Many reels ship with a spare spool, which is a cheap way to carry two line types. Braid on one, mono or fluorocarbon on the other, swapped in about ten seconds.
Fill a spinning spool to an eighth of an inch below the lip. Line that sits above the rim will come off in coils.
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Where this comes up
The guides that use spool and show it on real gear.
Spool is one of 206 terms in the glossary.
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