Drill Bits and Taps
A G1/4 port has to be tapped into whatever you are adding it to, and taps are what cut that thread. Common jobs: adding a fill port to a case panel, threading a custom block, or repairing a stripped port.
FORUM screw tap bit kits cover G1/4 and G1/8, the two threads used across water cooling hardware, plus bore-through taps in M3 and UNC 6-32 for case and radiator hardware. ModMyMods supplies a high speed steel British Standard thread tap.
Drill the pilot hole to the correct size for the tap or the thread will either strip or refuse to start. Go slowly, back the tap out every turn to clear the chips, and use a cutting fluid on aluminum.
