Once a hole is started in stainless steel, don’t stop or reduce pressure until the hole is finished. No matter what type of drill bit is used, drilling stainless steel builds intense heat quickly.

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 drill bit without reacting with the brass.

So it’s always a joy to pick up a new trick, especially one as simple as putting a hardened edge on mild steel using a drill bit as a filler rod. This tip comes to us by way of [Jody], aka ...

There are three tool options to consider when drilling large-diameter holes in thick steel: twist drill bits, hole saws and ... bore annular cutters can be used with hand-held drills, but they ...

whereas cobalt is typically used for harder materials like cast iron or stainless steel. Tungsten-carbide tipped (TCT) and titanium nitride coated (TiN) drill bits are also popular. HSS is hard ...