Dinking. Yes, dinking.

So, you know how some 45s have those big center holes? Well, they didn’t start out that way. They were pressed with a small center hole and then dinked.

Dinking is a form of die-cutting. The ASM Materials Engineering Dictionary defines dinking thusly:

dinking – Cutting of non-metallic materials or light-gage soft metals by using a hollow punch with a knife-like edge acting against a wooden fiber or resiliently mounted metal plate.

Here’s a video of some guy dinking a 45 by hand (or foot, in this case) with a dinking tool:

Have you ever come across a 45 that has a slightly off-center hole? Maybe an old reggae 45? That’s probably because someone used another method of enlarging the center hole, or the record moved when it was being dinked.