The problem I'm addressing here is the fastex buckle getting caught in the main compartment zipper because of the excess material in the panel/proximity of the buckle to the zipper opening.
Step 1: Materials
- 1/8" shock cord, one 4" length per buckle
I used a strong nylon thread because I like to overbuild things and this is what I usually use on cordura, webbing and other outdoor gear. Pliers are for pulling the needle through when pushing with the thimble isn't doing it (going through a couple layers of cordura and the shock cord, for example). Flame is to finish the shock cord by melting the end and you'd normally do for such synthetic material.
One tip when cutting the cord to length- I've found it's good to wrap the cord (or rope, webbing, etc.) with some tape so it doesn't immediately fray. It makes for a smoother end instead of a bulbous melty thing.