John,

It is not original, it's adapted from a technique I saw in a John Likakis book on deer hair bass bugs. He uses fender washers to shape the heads. He actually bends the washers to get different shapes (I have not tried that). If my memory serves me right (I gave the book away a long time ago), he coated the fender washer with Vaseline to keep it from sticking to the hair. I did not like this and use wax paper instead (parchment will also work).

Regards,

Alberto