On a Gigaminx you need 60 copies each of three parts of the smaller, 30 edges 20 corners and 12 centers. Far to many to cast one at a time. Most people print multiple of the smaller parts and make molds containing many. A good setup is:
Four copies of the small parts (15 casts), two of the edges/corners (15 and 10 casts required) and one of the centers. So 15 casts later you should have a Gigaminx.