Review on Yakamoz Combination Drill Deburr Countersink: Enhance Precision and Efficiency in Drilling and Deburring by Jim Bethea

I bought these to drill some holes in an aluminum mast on my sailboat. The two faucets I tried to use broke on first use. Aluminum is the softest metal to use these taps on, so I don't expect them to work all that well with something like steel.