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dw1 dw1 is offline
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Join Date: Sep 2007
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I had to replace some parts on the front clip of my daughter's car (someone backed into the car when it was parked) and drilling out a broken rusty bolt was required.

My existing drill bits (most of them good quality HSS) were a no-go for this task so I picked up a set of the DeWalt Cobalt drill bits: https://www.lowes.com/pd/DEWALT-14-Piece-Cobalt-Twist-Drill-Bit/50413714

These worked REALLY well for that job, and the centering feature was quite helpful, but I did notice two drawbacks with additional use:

1. If you drill a smaller "pilot hole" and try to go up gradually in size to enlarge the hole, the lack of a stand point angle on the flutes for centering is a problem.

2. Because of the unique point geometry, they can't be effectively sharpened by any means I have available, and I have a "Drill Doctor" sharpening tool as well as a standard-type bench grinder.

Despite these drawbacks, I very highly recommend these for anyone needing to drill into or through hard metals.

And remember: Cutting oil is your friend.
Old 10-21-2021, 12:08 PM
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