Often I need to extract broken bolts / screws and am thinking about picking up some left handed drill bits. Usually I have to extract broken steel bolts and screws from aluminum heads and manifolds. Most often they are broke off clean and need to be drilled. When looking at drill bits to purchase, I see they are made of HSS, Cobalt and Titanium. What drill bit material is the best for staying sharp and long lasting life?
Also, please comment on grabit and other extracting methods. What do you think is the easiest way to remove a broken bolt?
Thanks for any advice Pat