Use acetone to wipe off uncured polyester resin (MEK or polyester thinner also work); once it’s cured, removal is strictly mechanical—scrape and sand. For more tips, read the full blog post

CSM, woven cloth, roving, and biaxials (e.g., 1208/1708). Not for SMC/non-polyester plastics. Avoid EPS foam; safe with PVC, PET, PU cores.

Avoid thinning for structural work. If absolutely needed, advanced users may add ≤5% styrene. Do not use acetone to thin.

At ~77°F: 8–15 min pot life (mix size & %MEKP dependent), sandable in ~2–3 hrs, full cure ~6–8 hrs.