Conical drill bits

Given the nature of my work—and my hobbies, for that matter—I often have to do more than just solder; I also have to drill. So I picked out some special drill bits in advance for the AliExpress sale on March 25.

This is my first review on Muska, but not my first review overall.
The package arrived in a plain padded envelope. No boxes or extra packaging.
Though I was more worried that the package might damage the post office than that the post office might damage the package.


As you can see in the photo, the bits tried to make a run for it on the way, but the post office delivered them before they could get away.

All in all, the packaging gets a solid A. The envelope is sturdy, and nothing could have fallen out. They’re obviously not glass, so there was no need for more careful packaging. The bits were coated with a very thin layer of thick grease.

These bits are very handy for drilling large-diameter holes in thin materials.

They don’t wander while drilling, and they’re easier to use than starting with a bit of the required diameter. Plus, each one replaces a whole set of bits in different sizes.

I tried to buy bits like these in my city, but when I asked around the market, only one person understood what I was talking about. He thoughtfully pointed at the sky when I asked about the price and declared that one little bit like this cost about 10 bucks, but it wasn’t worth stocking such an expensive item. Well, good luck to him; China to the rescue.


The bits have the following diameter ranges:

1. 4–12 mm (6 mm shank)
2. 4–20 mm (7.5 mm shank)
3. 4–32 mm (9 mm shank)

The shank is machined to fit a three-jaw chuck, so the bit won’t spin in it, which is very convenient.

Unfortunately, I haven’t had a drill at home for quite some time, so I could only test the smallest bit. My cordless screwdriver won’t grip anything larger than 6.5 mm (7 mm at most, if I really try).


I compared the bit with a 4 mm bit for stainless steel made by Ataka (I should say, they’re pretty good bits with an unusual grind).

I drilled the first computer power supply case I could find (don’t worry, it was dead before the experiment).


Both bits—the Ataka and the step bit—drill at about the same speed (naturally, I compared them at the same diameters), but I got carried away and drilled a 12 mm hole.

It drills very easily, and thanks to its conical design, the bit doesn’t wander (I tried to make the holes in a straight line in the photo).

It doesn’t curl or catch the metal (as can happen when drilling thin metal with a large-diameter bit). If you stop before drilling all the way through, you can use the next diameter to countersink the hole after drilling it to the required size.

Here’s a closer look at the drilled hole


The first hole is 4 mm, drilled with the step bit without countersinking; the second is 4 mm, drilled with the Ataka; the third is 12 mm, drilled with the step bit.

After the test, the bit only had a few metal shavings stuck to it; the coating is pretty good.


All in all, this product gets a solid five out of five. It drills beautifully, and the grind and centering are good. It’s definitely worth the money.

I paid 9.09: the original price was 13.05, minus 15%, minus a 2-buck AliExpress coupon for purchases over 10 dollars. But even at the original price, it’s an excellent product. I recommend it.

Too bad I can’t check the steel grade.

I hope you found this review useful.