Your cart is empty.
Your cart is empty.Product Description
Cody W Colvin
Reviewed in the United States on March 31, 2025
I have a hobby machine shop in my garage so I'm always in need of very specific drill sizes. I ordered these 4.0mm drills because that is the perfect size for creating a #10-32 tapped thread. The drills come packaged in a flimsy cardboard box with a sealed plastic bag inside. The size is difficult to read, and without a case it'll be hard to know what size you have in hand. I will need to get my own container and mark it with the 4.0mm size. The bits themselves appear to be of reasonably good quality considering the price point. The cutting edges are sharp. The chisels are uniformly and symmetrically ground. The flutes are not very deep, so using these in softer materials such as wood or plastic may cause them to become easily clogged. I ran a few test cuts on my metal lathe, which is a very precise and rigid machine. My test bit did a great job of cutting through a hardened grade 8 bolt. The chips were nice and uniform with no clogging of the flutes. I measured the test hole at 0.162" (4.115mm). This is actually what you'd expect from an inexpensive drill bit. I've tested dozens of bits in my lathe and they usually range from 0.002" to 0.015" over nominal size. This one came in at 0.0045" over, which is not excellent but really isn't that bad. It will be serviceable for my #10-32 tapped holes with the drilled diameter giving me a 69% thread. I'd prefer a 75-77%, but this is close enough for most projects. If you're drilling clearance holes then you probably don't care much about a few thousandths of an inch either way. Overall I find these bits to be a good value with very serviceable performance in my shop.
Roy G.
Reviewed in the United States on March 31, 2025
I used these to be able to tap M5 threads. They are by far some of the sharpest bits I have used to drill steel.
B
Reviewed in the United States on March 25, 2025
These 4mm drill bits are functional and holding their sharpness so far, though I’ve only used them on softwood. At about 3 inches long, they provide decent reach for general tasks. I can’t say how they’ll hold up on harder materials yet, but they seem well-made for the price. At the time of review, they’re $6 for a 6-pack, which feels fair.
Judy
Reviewed in the United States on March 24, 2025
Decent bits. I use them for pin holes and weight reduction in the handles of the knives I make. These bits last almost as long as the higher priced ones that I have purchased from major machinery companies. For the price, these may be my new go to. On your carbon steels keep you speed slow and use your cutting oil.
Trickel
Reviewed in the United States on March 13, 2025
I'm always looking for new sizes of bits to add to my arsenal. I thought these would be a good size to have.I've only used one of the bits to test it out on some mild steel, it drilled through without any issues and surprisingly made a pretty clean hole. I haven't tried it on any harder metals so I don't know how it would hold up to hardened steel. I'm sure it will work great for most softer materials.I will update my review after I've had more time to use the bits. But so far I think they're a good value, at $1 per bit at the time of prchasing.
Killobyte DIY
Reviewed in the United States on February 27, 2025
I recently purchased the PATIKIL 3.2mm Drill Bit (12 pack) to make pilot holes in metal before cutting out spot welds, and overall, I’m very impressed with its performance.Pros: These drill bits are straight and very sharp, making them ideal for drilling into tough materials like metal and steel alloys. They cut quickly and smoothly, reducing the effort needed for pilot holes. The M2 high-speed steel construction ensures durability, and the black nitride coating helps to prolong the life of the bits, making them a solid choice for frequent use. The yellow treatment gives them a unique look and additional resistance to wear and tear, making them feel premium.Cons: The only downside I’ve noticed is that the price isn’t the most competitive compared to other similar products on the market. While the performance is excellent, you might find slightly cheaper options elsewhere.Overall, these drill bits do exactly what they’re supposed to do and will likely last a long time due to their quality construction. I’m happy with my purchase and would recommend them, giving this product 4 out of 5 stars.
Kimmelane
Reviewed in the United States on February 27, 2025
Not a dril bit size that I use a lot, but good to have. 6.5 mm is .005+ larger than a 1/4". This makes it good for a drop in hole for a 1/4" screw or bolt.
Ben Tanko
Reviewed in the United States on February 23, 2025
These arrived in great condition and ready to go to work. The tips are sharp and the few I put in my press were straight and true. I plan to use them for metals for boring the initial holes while I do my DIY projects.I am happy with my order and I hope this was helpful. ✔️ Thanks!
Recommended Products