Someone told me not long ago that those are not yoyos. I don't remember the conversation real well but as far as I'm concerned they are yoyos. I learned this method years and years ago when someone had a lesson out for making grapes to be appliqued. She used a penny for the size. But I find metal is hard to use. It gets too hot and it is too thick. I prefer to use thin cardboard. It does tend to buckle a little when ironed but it doesn't affect the yoyo any. I tried metal washers but didn't like using them. Too thick and too hot when ironed.