Used in the manufacture of "Home-made" filler paste, harder to sand than conventional bodyfiller but more waterproof. Mix in with a Polyester Resin after adding catalyst to ensure correct mixing if possible.
Can be used in casting to increase weight of the cast, ie chess pieces ect.
Can I use talc in gelcoat as a filler on my boat?
You could use talc to make a smooth paste for repair work but if it's going under water or in contact with water for prolonged periods then talc is probably not the best choice as it will increase the water uptake in the repaired areas. If you are using white gelcoat then adding fillers like talc will throw the colour off so you won’t be able to get a colour match on the repair. Alternatives would glass bubbles, or you can thicken up the gelcoat with a thixotrope like cab-o–sil / Colloidal silica.