Rated 4.1 out of 5 by 64
Rated 4.0 out of 5.0 by DIYken Drills through rebar
I was using a 7/16 inch drill bit to drill 8 holes into concrete with rebar.
The package suggested it was good for that.
It was not. It burned up when it hit the first piece of rebar in the first hole. See picture.
Then I got a Dewalt 7/16 inch Titanium bit that was supposed to drill through concrete and rebar.
It dulled as soon as soon as it hit the rebar.
Then I got a Bosch Xtreme SDS hammer 1/2 inch drill bit for the concrete and rebar.
I stopped when it hit the rebar.
Then I used this Rigid Cobalt 1/2 inch bit and stopped when it went through the rebar.
I don't know if the Dewalt is still good or not as I may never drill a 1/2 inch hole in concrete again.
It drilled through the concrete, but stopped immediately when I hit the rebar.
It drilled through 6 pieces of rebar with the Rigid, but I didn't push it when it hit the concrete.
I don't know if this Rigid is still good or not.
I don't know when I will ever need a 1/2 inch hole in any steel again.
I will keep it and find out someday.
October 13, 2015
Rated 1.0 out of 5.0 by don returned pretty quick
bought a set of ridgid cobalt bits on clearance at home depot to install some hardware on doors at a church here in town. i tried to drill through a push plate for a bolt using a 3\8 bit. all it did was spin. ive read how far superior cobalt bits are to titanium but now because of this purchase I am skeptical.
February 11, 2016
Rated 5.0 out of 5.0 by BuffaloJohn Finest Drill Bits
These cryo treated cobalt drill bits are fantastic. I had a project that had a lot of rivets into 1/8" steel and 26 gauge sheet metal. I started the project with a TiN bit, thinking it would do the job, way too much work. These holes I made were drilled with a corded drill, free hand, standing and kneeling and in awkward positions, so it was hard to keep the drill aligned. After four holes with the TiN bit, I switched to this bit. Over 300 holes later, I was still getting curls, the bit was showing a little wear, but holes were made quickly. If you have to drill metal, use these bits...
October 6, 2015
Rated 4.0 out of 5.0 by dennis 1/2 in. Cobalt Drill Bit
It did what I wanted it to do without any problems.
November 12, 2015
Rated 5.0 out of 5.0 by dyleone best pilot for hole saw
These are the best size as center pilot for 1/2 and 3/4 hole saw.
September 15, 2015
Rated 1.0 out of 5.0 by Starmapper 1/2" Rigid Cobalt Drill bit - One star for one hole
I bought this bit to finish drilling 4 holes in 1/4" steel tubing. I had already drilled up through 7/16" so this bit only needed to remove 1/16" of steel. It cut the first hole quickly, then wouldn't cut the other three. I resharpened the bit a total of 6 times to finish the other three holes - tough since it's ground at 142 deg instead of a more standard 135 deg. I kept the bit at low speed and used cutting oil but most of the time the bit just spun. I had to angle the bit repeatedly to get any cutting action, which left the hole pretty ragged. It took almost two hours to finish 3 holes. Other reviewers reported this as a hit-or-miss drill bit. It was a total miss for me. The Chinese quality control process needs much improvement.
June 6, 2015
Rated 4.0 out of 5.0 by kenm good in a pinch
Bought this drill bit in hopes it would do better than the mac tools drill bit I ruined. Surprisingly it did pretty well I was hand drilling a grade 10.9 metric bolt (slightly harder than grade 8 SAE) I was ablt to complete the repair.
August 25, 2015
Rated 5.0 out of 5.0 by Cypressdweller Long lasting.
Really shape and held its edge for over 100 holes in 1/4" angle iron.
August 25, 2015