I have a few of these Marples & sons cast steel centre bits that lost it’s centre pin (for the lack of a better term) somewhere between the late 1800’s and the present day. You might remember a post where I fashioned a so called Brace Bit Birdcage Awl from one of these bits some months ago. In the photos below you will see a centre bit that is still completely functional and one that I converted into a marking all-rounder. By this I mean a tool that is compact (can be carried around in my custom made leather shop apron) and functions as a marking knife as well as a birdcage awl. If you click on the pictures they will open up in a larger format, which should help to explain how the shape of the cutting end would accomplish the all-rounder status. I wrapped some leather around the shank for a comfortable grip.