SK4 / SK4S

Polyester spray filler grey/dark grey

Polyester spray primer for finishing the models and filling surfaces.
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.


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; add 1% – 2% of CT21 hardener (MEKP, Butanox M50 or equivalent) to SK4S. 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


See other Primers