[Izzy]

Good lubricant always helps

Once you break through the black cladding on tamiya rails or just starting out on aftermarket rails you get into that nice soft aluminum.

Since most of our parts are common low alloy aluminum it is fairly susceptible to gumming up a drill bit. By gumming up I mean the aluminum pastes itself to your drill bit or especially thread taps. By using the lube it helps to keep the drilling point cool and gum free.
A gummed up drill bit might wonder off center. Especially since it typically only gums up one of the two cutting surfaces.
A gummed up tap will strip out those nice threads as you reverse and back that tap out.

Try to always use a center punch. A must for keeping centered on the mark.

Izzy