Thread cleanup questions

some taps, like the smaller sizes have crazy lead in lengths that will never clean the bottom threads of a blind hole. Chasers are like taps that have been cut off: full length threads with a flat bottom. I use a brass wire wheel on bolts, its just what I have but have used a regular wire wheel as the bolts are pretty hard anyway. whatever you use, turn it back and forth so as not to load up the tap and bind it.