pin chuck
A small diameter steel rod goes in the flat (1/8"????)
So you need to find a rod.
Drill a hole the diameter of the large pin in a block of wood
With the flat up put the small rod on it an slide the blank on.
Lock the spindle and turn the blank which rolls the rod on the flat and locks the blank in place.
To remove the blank lock the spindle and turn the blank the other way.
If you would with green wood be sure to take it off the pins in an hour or the wood can warp closing on the pin then you have to chop it free with a chisel.
Works like a screw chuck but on and off is much faster until you looks the little rod.
Interesting. I'd considered getting a pin chuck a little while back but came to the conclusion from a little research that a screwchuck like the Oneway woodworm screw is just about as fast and likely more versatile—but I'd be open to hearing what others have to say.
Never thought of a nail. I have cut little steel rods that come In short lengths.check a 16d nail