Yes, don't sand blast !!!! I learned the hard way that it chews up the surface leaving a texture that takes longer to season and get the smooth non-stick surface your trying to build up.
Plus, it drives silica dust into the grain of the cast iron. Those tiny dust particles then can come loose later, lifting small particles of the carbon layer from the burned-on lard/oil that is the non-stick surface you want. That can lead to rust spots and food sticking.
And, avoid long cooking times of high acid foods in cast iron. I trashed the seasoned surface of a Griswold Dutch oven by a long session of cooking spaghetti tomato sauce in it.