I have watched Philadelph's and Undream's videos on pinning and have a question as to the dynamics involved here. They both use the "hammer method" as an anvil with small holes drilled into the side of the hammer. I understand that the round bottoms of the holes help to keep the rivet heads from too much flattening, but I do not understand where and how the washer fits into the device. Does the washer need to be in the hole with the rivet head or is it intended to sit up on the shoulder and only allow the rivet to nest in the hole? I'm pinning my first restore today and really want to get it right. Thanks in advance for any help.