It turns out that a hot solution of alum (ammonium aluminum sulfate), which is available in the spice rack of your local supermarket, will dissolve the steel ... for larger drill bits, but the ...

Learn More › When you need to precisely drill through metal, cobalt drill bits are the only answer. These powerful drill bits ...

Especially in steel thicker than ¼", twist drill bits will require extra pressure, lots of lubrication for cooling and some profanity — especially when trying to use a hand-held drill in an ...