All you need to remember is that 0.4mm = 1/64th inch (actually 0.396875mm = 1/64, but most times this won't matter)

So, 5/64 = 5 X 0.4 = 2mm

and 1/16 = 4 X 04 = 1.6mm (1/16 = 1.6mm is probably the easiest of all to remember)

From this you can usually multiply your way to any conversion you need.


Terry