1. finishing washer
2. 807 size stainless steel piping cone for icing cakes and pastries
3. fender washer to fit inside the piping cone
4. normal washer
6. carriage bolt
Just stack the parts in the order listed setting the bolt at the top of the cone. The only tricky part is to make sure the fender washer is perpendicular to the axis of the cone.
That's it!! Although not the most accurate it will work in a pinch.