The hole through the handle is just plain handy when working with silver or gold wire.
The pliers used for drawing wire are pretty beefy, and usually have a hooked handle on one side. If you are drawing wire by hand uou rwally need a good grip. The end you grab is scrap. It has to be filed or worked down to thread through the drawplate.
A drawplate consists of a bunch of holes, graduated in size, tapered woth the larger size on the back and to size on the front. Anneal the metal, apply some lube, stick the tapered end through a drawplate held in a vise, and pull. Sometimes you can pull a couple sizes before annealing.
The plates come with different shape holes. Square, triangle, etc. To get half round (like to make a ring) you pull two wires together through a round hole. They will be flat where they draw up to each other.
More often, instead of hand pulling the wire, a draw bench is used. A draw bench is a narrow (maybe a foot or so) long (5-7 feet?) bench. At one end is a holder for the drawplate. At the other end is some kind of winch. Old benches had a huge handwheel. The winch pulls a cable or chain with a loop on the end that catches the hooked handle on the pliers.
After pulling the wire, when fabricating, hand clamps help hold small parts. A hole through the handle is very ergonomic. In many situations it could get complicated - without a hole to hold the wire straight up. When held at right angles a wire has a tendency to bend, held straight it is supported for 4" or more.
Chilly
