I'm making some shifter and brake pegs for a friend's bike , and have run into a small problem . I suspect I have work hardened the SS when I drilled it , because I've never had this much trouble cutting threads . I have units made and drilled 3/16" diameter and about 1 1/2" deep , but need some advice . The threads are to be 3/8-16 , and only need to be about
1 inch deep . The first one I drilled like 2 inches deep , in 2 steps (after a 3/16" pilot hole). The piece was quite warm when I finished . Should I take these out to the tap drill diameter in 1 step ? Should I use coolant , and if so what kind ? The pegs are slotted 1/8" slots spaced 1/8" apart (done with a parting tool) , and got very warm during this machining , could that have hardened the SS some ?