Corkscrews

[navihawk]

Great... can you elaborate please on the last comment ... some of them look hammered out? Thanks very much.

Some of them, the grind looks forged, or ground flat, like a true spiral, instead of round like a spring. How do they make them?

 

[smiling-knife]

There are three different basic types of worms and variations within types. The wire helix is made by bending a wire around a steel rod. The wire helix can be left round e.g., top left photo 1, or can be cyphered (bevelled) e.g., 4th from the left in the top row photo 1, or can be fluted (grooved) e.g. smaller one with the hook photo 1. The centre-cut worm is lathed from a steel rod e.g., bottom left photo 1. The centre-cut can be square or bevelled. A bevelled, centre-cut is also called bladed. There is also an archemedian worm made by a lathe. These have a solid central shaft with blades. e.g. NE compass location in photo 2. I hope this makes sense.

Photo 1

Photo 2

 

[navihawk]

The ones made on the lathe look more robust. Better looking also IMO.