The sanding of the gelcoat can be done as a final process that moves on to polishing. When sanding as preparatory work for the touch-up and a new application of gelcoat or topcoat, some basics must be observed in order to ensure an optimal basis for the renewal.
Remove stickiness by excluding air
One of the most hindering properties of gelcoat or topcoat is the stickiness of the surface, which all abrasives clog quickly. The stickiness must be eliminated by excluding air. Plastic sheeting is placed on the areas to be sanded and sealed airtight around the edges with adhesive tape. The stickiness will disappear after two to three days.
Gelcoat should be processed with an average sanding speed of a thousand revolutions per minute. A 2000 grit is recommended for the initial sanding, followed by a 3000 grit. The sanding pad must be moved slowly over the gelcoat in circular movements.