Drop Fill Guitar Repair With CA Glue — A Nashville Luthier Shows How It’s Done
A drop fill is one of the most common guitar finish repairs — a small ding, divot, or scratch filled with cyanoacrylate glue and leveled flush with the surrounding finish. Done right, it disappears. Done wrong, it makes things worse. Colin O’Brien of Little Creek Instrument Repair in Nashville, a luthier who works on instruments for some of the biggest names in town, walks through the process using Zap CA glue and Flexi-Tips. This is how it’s done.
PRODUCTS USED
ADHESIVE — Zap CA (Thin / Pink Label)
APPLICATOR — Zap Flexi-Tips
LUTHIER — Colin O’Brien, Little Creek Instrument Repair
LOCATION — Nashville, Tennessee
WHERE TO BUY — zapglue.com
WHAT IS A DROP FILL?
A drop fill is a guitar finish repair technique used to fill small voids in the finish — dings, chips, divots, and checks — with cyanoacrylate adhesive that cures hard and clear. The CA glue is applied in controlled drops directly into the void, allowed to cure, then leveled and buffed until it blends invisibly with the surrounding finish. It is one of the most practical skills any guitarist or builder can have, and CA glue is the go-to material for the job on both nitrocellulose and polyester finishes.
Thin viscosity CA — like Zap CA with the pink label — is the right choice for drop fills because it flows into tight voids and levels itself before curing. Flexi-Tips give you precise control over where the glue lands, which matters when you are working near binding, frets, or delicate finish edges.
ABOUT THE LUTHIER
Colin O’Brien runs Little Creek Instrument Repair in Nashville — a shop that works on stringed instruments for some of the most notable players in a city full of notable players. Nashville’s instrument repair community is among the most demanding in the world. The techniques Colin demonstrates in this series reflect real professional practice, not hobbyist approximation.
THE FULL ZAP GLUE REPAIR SERIES
The drop fill is one of four guitar repair techniques covered in this series with Zap Glue and Little Creek Instrument Repair. Watch all four.
WHY CA GLUE FOR GUITAR REPAIR
Cyanoacrylate adhesive has been a staple of professional guitar repair for decades. It cures clear, cures hard, bonds to wood and finish materials, and is available in multiple viscosities — thin for drop fills, medium for general bonding, thick for gap filling. Zap is one of the most trusted CA brands in the lutherie community. The Flexi-Tips applicators in this series solve the perennial CA glue problem — controlling where a fast-curing adhesive lands before it goes somewhere you don’t want it.
GI VERDICT
Mike from Zap Glue hangs out with a Nashville luthier that repairs stringed instruments for notables around town. Here is one great use for their CA glue. CA glue is one of the most useful things in any guitar builder or repair person’s shop. Zap has been the go-to in professional lutherie for a long time — the CA community trusts it for a reason. What Colin demonstrates in this series is not exotic or complicated. It is practical, repeatable technique that any serious player who works on their own instruments should understand. Watch all four videos. The binding repair alone is worth your time.
— GI
About GI — GuitarIntel’s gear desk. Fifty years of guitars in hand, vintage and new, electrics built from scratch, amps modded, pedals stomped. The first thing I ever wanted, at age 5, was a guitar. Everything since has been in service of that. GuitarIntel exists because gear deserves straight talk from someone who loves guitars and gear and might be a little obsessed.
Published June 29, 2026 — GuitarIntel
