Precision Twist C29R10CO Cobalt Steel Jobber Length Drill Bit Set with Plastic Case, Bronze Oxide Finish, 135 Degree Split Point, Inch, 29 Piece, 1/16" to 1/2" x 64ths

The description of the Precision Twist C29R10CO Cobalt Steel Jobber Length Drill Bit Set on the Amazon site was inadequate. There was no description of each drill having a pilot bit and a triangular shank. Since I work primarily in wood, I found that pilot bit tends to pull the bit into the wood too quickly causing tear out. This happens every time with a hand drill. Using a machinist lathe lets me advance the cutting drill bit more slowly resulting in a precision cut hole. The shanks are still being evaluated. However, the shanks on my prior twist drill set were very galled, so much so I had to grind off the metal or turn the galled drill on the lathe.I do not know if the shanks will stand up to drilling metal. In short, I think the drills will work fine for my precision work making custom pool cues.

Worth the money.

Arrived in a "Plastic" drill index not "Metal" as the description stated.

When I ordered these I was under the impression that they where made in America. After receiving them they said that they where make in Brazil.

Really nice bits, I've only used them to drill a few holes but they seem to drill into the material smoother. I bought a new R size bit recently and have had to use that to drill the same aluminum that I've drilled with these and it really doesn't seem to compare; the R sized bit is just HSS with a TiN coating and it doesn't drill as smooth as these.