Gel Coat Application:

Patching Guide

 

Problem	Probable Cause
Dull Surface	Requires additional rubbing out with compound.
Low Gloss	Requires additional rubbing out with polish and wax.
Off-Color Patch	Different production batch of gel coat material. Dirty materials and/or equipment. Improper catalyzation. Dirty repair area.
Patch Lift-Off	Improper cleaning and repair.
Wet Patch	Improper catalyst ratio. Temperature too low.
Porosity in Surface	Excess air in gel coat. Water contamination. Application techniques. Patching material too thick.
Scratches/Sanding Marks	Sandpaper grit too course. Dirt or other foreign material on the buffing wheel. Under-cured patch.
Flaking and Cracking	Gel coat material not cured prior to sanding. Improper catalyzation.
Depressed Area	Wet sanding with too small of a sanding block. Sanding with finger as opposed to using sanding block. Excess exotherm on cure. Patch area not properly filled.
Smeared Surface	Acetone not wiped off surface. Contaminated material. Patch not sufficiently cured.
Ring Around Patch	Edges not feathered or sanded properly. Porosity in original gel coat material which may require re-spraying. Under cured patch.
Reappearing Crack	Crack was not fully ground out. Weak laminate.
Glossy Patch, Dull Part	Original gel coat was under-cured. Buffer developed too much heat.
Porosity or Void in Patch	Improper spray or leveling. Improper mix of filler. Trapped solvent. Air not worked out.
Patch is Below Surface	Not enough allowance for patch shrinkage. Be sure to overfill repair area. Do not sand and finish until patch is cured.