I think it is a good idea to start and stick with one type of steel while learning to forge blades. For large and small knives, I think 5160 would be a good steel.1/4" x 1" bar stock would be a good size to start with. I've made several knives from 5160, and it is one of my favorites, and it's easy to work with. I forge mine at about 1500-1600 degrees. Normalize 3 times, anneal 3 times, quench 3 times(in oil heated to about 160 degrees), and temper 3 times. A Google search for "forging 5160" steel will probably load you with information. Hope tis helps,