Crystic Gelcoat Quality Guide

Product catalog summary

Introduction
This document is a Gelcoat Quality Guide provided by Scott Bader, a company with over 50 years of experience in reliability and innovation in composite applications. It addresses common application faults in gelcoat and their possible causes.

Common Gelcoat Faults and Causes

Colour Tearing: Caused by pigment separation from resin, improper spray technique, and long geltime leading to sagging.
Gelcoat Peeling: Results from contamination, over-curing, and long geltime dissolving release wax.
Water Marking/Etching on Mould: Occurs due to thin or double gelcoating, use of two colors, and solvent attack.
Parallel Cracks: Caused by flex cracking, excessive gelcoat thickness, and thin or flexible laminate.
Gelcoat Blisters: Arise from air voids, unreacted catalyst, and solvent contamination.
Wrinkling: Due to insufficient cure, thin gelcoat, and rapid back-up.
Blisters in Laminates: Caused by water ingress, damp reinforcement, and air voids.
Star Cracking: Results from reverse impact, thick gelcoat, and crack patterns from mould.
Fibre Pattern: Occurs when gelcoat is too thin, high exotherm in laminate, and insufficient cure.
Dimpling: Caused by heavy wet-on-wet spray application, insufficient consolidation, and contamination.
Colour Mottling: Results from low thixotropy, poor pigment compatibility, and low viscosity.
De-Wetting (Brush): Occurs when brush gelcoat is applied too thinly, incompatible release system, and contamination.
Colour Specks: Caused by poorly ground/mixed pigments, contamination, and poorly maintained equipment.
Sagging: Results from thick gelcoat, long geltime, and low viscosity/thixotropy.
Porosity: Occurs when gelcoat is too viscous to release air, cold gelcoat/mould, and quick gelling trapping air.
De-Wetting (Spray): Caused by thin spray application, incompatible release system, and contamination.
Crazing: Results from chemical attack, excessive heat, and contamination.
Colour Separation: Occurs due to insufficient mixing, sagging, drainage, and poor application.

Contact Information
Scott Bader provides contact details for their offices worldwide, including locations in the UK, France, Spain, Germany, Ireland, Sweden, Czech Republic, Croatia, USA, South Africa, Dubai, and China.

Catalog excerpts

Gelcoat Quality Guide A guide to application faults and possible causes Over 50 years of reliability, experience and innovation

Open the catalog to page 1

SCOTT BADER COLOUR TEARING • Pigment separated from resin • Improper spray technique • Long geltime, sagging COLOUR SEPARATION • Insufficient mixing • Sagging, drainage • Poor gelcoat application COLOUR MOTTLING • Gelcoat loow in thixotropy • Poor pigment compatibility PARALLEL CRACKS • Flex cracking • Gelcoattoo thick STAR CRACKING • Reverse impact • Gelcoattoo thick • Crack pattern transferred from mould • Chemical attack • Excessive heat • Water ingress • Damp reinforcement GELCOAT BLISTERS • Unreacted catalyst • Solvent contamination FIBRE PATTERN • Gelcoattoo thin • High exotherm in laminate...

Open the catalog to page 2

Scott Bader Composites Europe Scott Bader Group Companies HEAD OFFICE Scott Bader Company Limited Wollaston England Tel: +44 1933 663100 Fax: +44 1933 666139 email: [email protected] Scott Bader Ireland Dublin Ireland Tel: +353 1801 5660 Fax: +353 1801 5657 email: [email protected] Scott Bader Inc Stow, OH USA Tel: +1 330 920 4410 Fax: +1 330 920 4415 email: [email protected] Scott Bader SA Amiens France Tel: +33 3 22 66 27 66 Fax: +33 3 22 66 27 80 email: [email protected] Scott Bader Scandinavia AB Falkenberg Sweden Tel: +46 346 10100 Fax: +46 346 59226 email: [email protected]...

Open the catalog to page 3

Crystic Gelcoat Quality Guide

Crystic Gelcoat Quality Guide

Catalog excerpts

All Scott Bader Company Limited catalogs and technical brochures