used to bore or drill holes in the PCB
A 12v Mini Drill is just a small drill with a 12 volt power supply. This can either be with an a/c adapter or rechargeable 12 volt battery.
You must be thinking of Dremel Mini drills.
use a half inch drill
There are a number of companies that maunfacture quality mini drills. Some of the best know are Draper, CEL, Bruder Mannesmann, Silverline and Am-Tech.
With great difficulty, but it is not impossible especially if you can glue, drill and cut the pieces as you want.
It is a small drill, a mechanical driving tool that may have bits that you insert to screw fasteners tighter or looser, mostly it has bits you insert that will carve or drill holes or also cut or sand things. It is so small it is called 'mini.' 12 v means it runs on 12 volts of electrical power, so it probably runs on a battery that can be recharged, but might also plug into house current with a DC converter to make it run on 12 volts of power.
A drill machine can mean a hand held electric drill, or a bench drill press or a pillar drill.
Drill using a 280 degree drill by samsung drill and drill about 5cm by 5 cm
With your drill
It's the part of the drill that holds the drill bit.
Drill Sergent
Depending on the type of drill BIT, it may drill through almost anything.