Hinge drill bit with 1/16 or 1.5mm drill?

The smallest have found is 5/64” roughly equivalent to 2mm which will do for a No. 6 screw in hardwood. From the sizes you have quoted I presume you need to pilot for No. 4.

Richard

The set I have seem to be 1.8, 2.7 and 3.2 mm As best my plastic vernier shows ...

actually just looking at the hex shank, they're actually marked 5/64,

Yes, although I prefer to pretend I'm modern and call them 3mm ;-) I've been using the 5/64 to get a start point and then finishing the pilot with a 1.5mm twist drill but it would be good to find a self-centring bit that was the right size. (Yes, I know I could make one but it would take a while and there are too many other jobs on the list already)