We Repeatedly Drilled into Three Types of Metal to Find the Best Cobalt Drill Bits
These powerful drill bits for cast iron, aluminum, and even stainless steel are made of a steel alloy of 5 percent to 8 ...
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The Best Harbor Freight Drill Bit Sets, Based On Reviews
If you're in the market for new drill bits for your next home improvement project, check out these products from Harbor ...
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Dissolve Steel Drill Bits In Alum From The Grocery
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.