How do you determine thread size to use when wrapping guides ?

Hi again Steve,
Use watever suits you best for the rod your building. Smaller threads like "a" and Madeira can be used for both under and over wraps all all sorts of rods from light weight to game rods. Thicker threads are stonger but you get more wraps over a guide foot with the smaller threads so they work out at similar strength. Thicker thread will give you a bit more abuse protection, but if you look after them the thiiner threads will work fine. Just avoid using a thinner thread over a thicker thread as you'll find it very difficult to avoid gaps.

ESFNEM Col
Port Kembla, NSW
Australia

A is usually used in all but heavy salt water rods On light stuff the small A will keep the finish to a minimum so there is not so much weight

Bill - willierods.com

Hey Col and Bill:

Thanks for the guidance, no pun intended.