Detecting Paper pin type small object with Inductive sensor or any Equivalent ?


I am planning to make metal detector which can sense small paper pin inside the Plastic Moulded part.

I tried conventional Inductive sensor but not working. Not able to detect small Stainless Steel Metal Pin.

Any idea which sensor can be used ?

How small is small?
How deeply embedded in the plastic?

Capacitive sensors can definitely detect stainless steel, but it all depends on the size of the stainless steel object. I’m using a capacitive water level switch as presence sensor for a stainless steel tray - the sensor faces a sheet much larger than the sensor’s surface, and works at a distance of <10 mm.

You need a small coil, what also requires changes to either the frequency or adaptation circuit.