Viking Opal 670 Sewing Machine Instruction Manual (Model Opal 670) - 68 Pages. Lost your sewing machine's manual? We've got you covered! This instruction manual is the ultimate guide to unlock the full potential of your Viking Opal 670. No more confusion or frustration—just clear, concise instructions right at your fingertips. What's inside? Everything you need to know from setting up to mastering your sewing machine and all its features.