Mixing Mud for Skim Coat

I use Z-Grip made by evercoat it has IMO and thiers the best adhesion properties and sands easy. If you want you can add polyester resin to it to thin it out or cause it to "flow". If you add resin you MUST incsrease the amount of hardner. Feather fill is a great product for the $$$ it really fills and sands easy. Make sure your final prime is done with a good high build primer I use PPG NCP 270 it fills well shrinking is minimal and has great adhesion.