13-Pc M35 Cobalt Metric Drill Bit Set, 1.5-6.5mm for Hard Metals

At the time I purchased these, I only intended to use them for light duty (drilling into polymer). However, as fate would have it, I had to use them to drill into hardened steel, and much to my surprise, they performed admirably. It was a pleasant surprise (I was expecting "Chinese junk") and I'm very happy with this purchase; especially considering that it's a METRIC set, which is difficult to find (in the USA). I wish the set had a 1mm bit, but oh well. It's just a preference, not anything against the quality of the bits in this set. ============= Update 1/16/18 ============= My rating has changed from 5 stars down to 3. I needed to drill into metal again--actually I wasn't even drilling new holes, but just "chasing" already existing holes to expand them--and neither the 4.5mm or 4.8mm bits would do anything. They just spun around getting hot, without cutting anything. I even tried the 5mm bit, even though that was too big for my purposes, and it also did nothing but spin. Thus, I've used four of the bits (4, 4.5, 4.8, and 5mm), and only one of them did anything. The one that actually worked did its job well; the others are a HUGE disappointment. ============= Update 1/25/18 ============= Kudos to Migiwata customer service (thank you, Bella!). After hearing about my not-so-pleasant experience with these bits, they sent me a second set. Apparently their original supplier had run dry, and they had to use a second, temporary supplier while the original caught up with demand. The first set that I received was from the temporary supplier. The new set is from the original supplier, and the bits seem to be in order in this new set. So how do you tell the difference? By the case (see photos). The set with the blue dot on the case--which is a plastic retainer to keep the case closed--is from the original supplier. Now if you happen to get a set without the blue dot, don't panic. Just because I got a subpar set that slipped through the manufacturer's quality control process doesn't mean that you did, too. Try the bits out first. WORST case is that Migiwata customer service takes care of you like they did me; best case is you don't even have a problem. As for me and my review of this product, I'm a happy camper again and am bumping my rating back up to 5 stars. The bits are great (make sure to use a good cutting lubricant/coolant) and Migiwata customer service is stellar.

I figured these were just Chinesium steel when I ordered them, but they appear to be High Speed Steel, which is pretty amazing at this price. I'm not sure if they're cobalt HSS M35, but they're at least M2. I've made probably a hundred holes hand-drilling mild steel auto bodies with no dulling or chipping. I even drilled out a 304 stainless screw in my press with these and a bit of patience. If you're looking for something to drill fastener holes for angle iron, I'd say these are the ticket. The only thing I would complain about is the titanium nitride coating (added for reducing heat and friction) extends down the entire shank of the bit, which makes the shank prone to spinning in the chuck as it scrapes off the coating into burrs. Still giving 5 stars though because of the price.

I have bought three of these sets . The drill bits are superior ! They used to come in better cases, but the case is pretty irrelevant for the most part -- it just acts as an index.

I needed a bit that would drill through a light weight gun safe. These did that perfectly. Thank you to all the people in the Amazon world who wrote so many tips in your reviews. That helped greatly. I used these bits with Forney 20857 Tap Magic Industrial Pro Cutting Fluid (which is also very inexpensive). I never thought of using this fluid to drill. They were the perfect combination. I drilled slow and straight on like some suggestions. The bits never dulled, or overheated I now have great drilling bits and fluid for my next adventure.

These drill bits are holding up pretty good they stay sharp even after being used a couple times . I use these drill bits Alot on 5.7 hemi exhaust manifild bolts, the bolts always tend to brake on the cylinder head and I have to drill into the broken exhaust bolts to extract them out and those bolts are pretty much hardened . These bits do there job and bite into The metal your drilling into right away with out walking off. The only down side is having coworkers who like to borrow your drill bits and loose them lol so I gotta buy maybe 2 more sets just to have as back up . There pretty good drill bits they hold up good , haven't had one go dull yet .

Unfortunately, the 2.5mm bit broke on my first try with these bits. Using a drill press on soft metal. Very disappointed. --Update 05/01/2018-- Customer service responded to my feedback and explained the bit might have been defective. They gave me a choice of a full refund or they could send me a set of 50 bits that would include 10 of the 2.5mm bits like the one that broke. I opted for the additional bits and i received them within 48 hours. In fact, they were delivered on a Sunday. The performance of the replacement 2.5mm bit was impressive. It did not walk at all and required very little pressure on soft and medium hardness metal. I would definitely recommend this product or any other product that Migiwata sells. With this level of customer service, you can't lose.

The 5 mm drill bit was essential repairing a broken 6 mm fastener securing the oil pan to the engine block. After an unsuccessful attempt to remove the bolt using a left hand drill bit and extractor, it was time to drill through the middle of the fasterner, the steel engine block, and tap new threads using an 6 mm x 1 Irwin tap. Adhering to the 60 percent rule of thumb of drilling 60 percent of the actual hole required, a 5.20 or 5.25 mm drill bit was needed, however this drill bit set had 5.0 and then 5.5 mm drill bits in its range. Using the 5.0 drill bit and cutting oil, the drill bit drilled nicely through the bolt and engine steel block. The drill bit did not wobble off center. The Irwin 6 mm x 1 tap from the metric tap and die set purchased from Amazon and using cutting oil cut new threads with ease. I was careful to only cut new threads applying no more than 1/4 or less clockwise turns and then reversing counter clockwise a 1/4 turn. Halfway through the tap I removed the tap completely from the hole, removed the metal shavings using cutting oil, and finished the tap. Installed the new oil pan gasket with the oil pan and torqued the bolts using a Carlyle torque wrench from Napa Parts store to 105-inch pounds. Vehicle back in action. Thanks Migiwata for your metric drill bits. I recommend using this set.

I am putting aluminum siding on a shed...I have some metal framing of 2" square tube steel and the aluminum siding... I drill because self starting screws will not go into the harder steel frames. However, self starting screws will go into aluminum siding quite easily. These drill bits would not even dig into the aluminum enough to throw one chip of metal... the tip walked all around barely scratching the surface... these might be ok for wood but definitely NOT for metal.

I like the fact that were as described and of great quality

Mala calidad de las brocas, se rompen facilmente.

I like this little set. After trying a couple others that were either too dull or too soft or both (and basically only good for 1 hole in steel), this one has taken quite an amount of (ab- and mis-) use and still doing strong. Drills through cast iron and mild still like a champ; can handle toolpost steel and stainless steel in both drill press and lathe. Will be ordering another set just to have a spare (and because the thinner ones did snap but that's my fault).

Excelente produto

Otimas broncas. Recomendo