Thickening Gellcoat

[slneatboat]

Does anybody know if there is an additive or filler that can be added to gellcoat to make it into a putty like substance.I also want the gellcoat to retain its original colour in this case white and be as water proof as its orginal state if possible.Thankyou

[8knots]

You can add microballons (hollow glass bubbles) this will thicken it up! It is a more expensive option but sands great. It will be somewhat more porus tho. So plan on a topcoat with surfacing agent. I don't know what kind of volume of mix you need but it takes alot to bring it to a fairing putty stage. You might just use epoxy then topcoat with your gelcoat
Good luck 8Knots

[gonzo]

Fumed silica (Cabosil or Aerosil) works well.