1/4 Inch Cobalt Drill Bits 2pcs Heavy-Duty Metal Drill Bit Set for Steel, Cast Iron, TiAlN Coating, 1/4" Hex Shank (1/4" x 4")

I ordered this 3/16" cobalt drill bit to drill holes through the bottom of our steel storm door. I had put a sign on the door directing delivery people where to put packages, but it was only attached with double-sided tape, and when the temperature dropped recently, the tape failed, and the sign fell off. I had been avoiding bolting it on because that would require drilling holes through metal, which I'd never done before. So, I asked the Internet what kind of drill bit would be best for the job, and the Internet said cobalt. The Internet was not wrong! The Internet also told me to drill as slowly as possible (to avoid heat buildup that can destroy the bit) while applying firm, steady pressure, so that's what I did. It took patience, but the bit grabbed the metal fairly easily and began to create curved shavings rather than dust. I was worried the drill might skip in the beginning, but there was no skipping or slipping at all. Slow and steady worked like a charm. There also seemed to be some debate about whether one should use lubricant or water to cool the bit, but this job was so simple that I didn't bother, and it worked out just fine. Keep in mind that the bottom of our storm door is a fairly thin sheet of metal, so I don't know how well these bits would do with thicker metal. They seem like a great value for the price, considering the small number of times I'll need to use them. I don't know how they would stand up to regular use. But I do have one more project in mind for this drill bit: putting a couple of holes into our steel mailbox to add a spring that will force the lid to close when someone (not saying who) leaves it open after retrieving the mail. I'm still figuring out how I will do that.

We ordered these for a specific job, which was drilling through our metal mail box at the bottom so that we could bolt it to the already-installed hardware on our brick wall. It was a fairly easy job and the metal was lightweight and not particularly thick as metals go. So it wasn't a particularly tough test I suppose, but at any rate these bits worked perfectly for our needs. We had unsuccessfully tried a few other bits that weren't specifically made for metal before getting these but all they were able to do is put a little divot in the metal rather than drill through it. So with the caveat that our job was relatively easy and the drill area already had divots to start it, these drilled right through the metal (I ordered the 1/4 inch bits) and made the holes we needed to complete our mailbox installation. In terms of the overall quality, weight, and sturdiness of these, they definitely feel and look as good as the last set of name brand drill bits we bought in person. Based on our use so far I'd consider these a great value, especially if you are just looking for a couple bits in a specific size and don't want to have to buy a whole set of metal drill bits in various sizes you will likely never use. I'm glad to add them to our stable of bits in our work and tool area, as I'm confident these will be able to tackle somewhat more demanding jobs in the future.

This is a nice little two pack of 5/32 cobalt drill bits. The 1/4 inch hex shank is especially handy since it works easily with impact drivers and quick change chucks. That alone makes them convenient to keep in a general use kit. They arrived sharp and have drilled cleanly through wood without any issues. I have not yet tested them on steel or cast iron, so I cannot speak to long term durability in metal. For wood applications, they cut smoothly and did not wander. The price point is reasonable, which makes them a practical option. If one breaks, it is not going to feel like a major loss compared to some higher priced premium bits. It would be nice if the manufacturer offered these in a full matching set rather than only individual size packs. That would make it easier to build a consistent collection. ✅PROS: ++ Sharp out of the package ++ Convenient 1/4 inch hex shank ++ Clean drilling in wood ++ Fair price for a two pack ❌ CONS: ++ Not yet tested in metal for durability ❗ NOTES: ++ Would be great if offered in a full size set 📌 SUMMARY: These hex shank cobalt bits are sharp, convenient, and reasonably priced. While not yet tested in metal, they perform well in wood and offer solid value for everyday use.

This product is a cobalt drill bit for cutting metal. The 5/32" size worked particularly well for me since I wanted to put an M4 bolt through the hole after and it matched perfect with no wiggling. Functionality was great, this went through steel and aluminum much faster than any other bit I've used. I suppose in factories, carbide might be better. For my hand drill, however, maybe cobalt is better. The only issue I had is that the tip had no brad point, just a wide wedge. I used a punch to mark where I wanted a hole first, but then the bit didn't seem to catch on that mark dragging it across or pushing it side to side before spinning up. I ended up making a little divot with a 3/32" bit from another vendor that couldn't cut nearly as well, I guess due to inferior materials, then did the real hole with this bit. Anyway, seems like great value for money. My drilling took ten seconds instead of a minute. I hear cobalt bits can be sharpened and reused too, unlike bits coated with carbide powder. So I'm looking forward to trying to keep it going that way once it dulls too.

These have come in super handy as of late. I needed to drill some steel tubing to plug weld a motorcycle frame, and this bit ate right thru with no issues. The best part is that it has a quick connect, so I could insert it into my impact driver, and make LIGHT WORK of just about any steel around me. The bits seem pretty strong, and they've stayed sharp so far. But I will say the tip does tend to walk a bit despite being a pilot tip, so you'll either need to drill a small pilot or use a very good and strong center punch to give it a place to steady at first. This could be because I was on round tube mostly, but I expected it to grab a bit easier still. No complaints.... if you're a DIYer and need a bit to drill holes in just about anything other than concrete these will get the job done. I've only been through one bit so far, and I've needed to drill several holes.