SK4 / SK4B / SK4S

Polyester spray filler

It allows to apply high thicknesses even in a single coat of spraying in several passes.
It is a very low shrinkage product, easy to sand and polish and has
excellent adhesive performance on wooden and laminate supports.
It is compatible with all paints.

SK4 (grey)
SK4B (white)
SK4S (dark grey)


Recommended: sanded fiberglass, impregnated wood, polyester fillers, modeling pastes.


Apply on well cleaned sanded surfaces; make sure that the substrate is free of dust, fibers, dirt and surface condensation. Dilute with acetone or MEK from 0 to 10% by volume. Add 3% – 4% of CT20 liquid hardener (cyclohexanone peroxide) to the resulting solution for SK4 and SK4B products; add 1% – 2% of CT21 hardener (methylethylketone peroxide) to the SK4S product. The quantity of hardener required depends on the temperature of use and the times of processing required. Let the product de-aerate for a few minutes before applying it; the application time of the hardened product varies from 20 to 30 minutes at 23°C in function of the quantity of hardener used. The recommended temperature range is between 16 and 28°C. Typical application by gravity spray gun 200-300 microns each coat to a maximum thickness of 800-1000 microns in few coats with 5 -10 minutes intervals between one and another; nozzle diameter 2,5 mm; air pressure 3,5 bar. Sandable after 4 hours from application at 23°C. Paintable with gelcoat or polyester paint after 4 hours; with other paints after 24 hours. Typical dry sanding cycle, grits: P150-P220-P320-P400-P600. The theoretical yield per m2 per 1000 dry microns of thickness, is approximately 1,8 KG. In its original packaging, the product can be used for 6 months if stored indoor away from direct sunlight, at temperatures not exceeding 20°C.


Type of use


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