It all depends on the size of the blank and how out of balance it is. Also it depends on what I'm making. For example if it's a bowl I'll use the inner screw holes on the face plate with longer screws (#12 screws work with my face plate holes) because that part of the blank is going to end up on the floor. I always drill pilot holes and most of the the #12 screws I use are 1" long. But screws bite real well with the species of wood I turn. Softer wood or wood that might be more prone to splitting would also play a role in my decision as to what screws and how many to use. Never had a problem but my first task is to cut a mortise for my chuck's jaws so I can remove the face plate and a slow speed. The screws I use are #3 philips. Since I drill a pilot hole they go in snugly but not so hard that I have to use a lot of force. This is one of those areas where you kind of have to learn what works for you as there's so many variables.