To attach a spring/coil end to a cord, place a tiny drop of glue at the very end of the cord, slide the cap/coil onto this end, and then use an old pair of either narrow flat nose or chain nose pliers to gently but firmly flatten the first two coils (those farthest from the end) tightly on the cord to hold the cap in place.
Let the glue dry thoroughly before adding the clasp. My mother likes to use watchmakers’ glue, you can find what works for you.
Although we do not stock the coil/spring type of end cap, you can view our selections of glues and findings here.
Answer contributed by Dale “Cougar” Armstrong