CML Supply Mini Micro Drill Bit Set and Pin Vise Chuck 31 pcs

I haven't had these very long so I can't say how well they hold up over time, but I figured I'd add some things I noticed.I'm making pinhole plates for pinhole cameras, so I'm mostly interested in the smallest bits. I also need them to be accurate because a difference of something like 0.001" or 0.01mm is enough to make a difference in image sharpness with precision-drilled pinholes in many cases.I put the smallest bit in a good solid micrometer outer caliper I have and it read exactly 0.013" as advertised. Note that these tiny ones are TINY. To give you some idea, the thinnest manual sewing needle I could find was wider than 0.02"/0.5mm. The smallest bit (0.013"/0.33mm) in this set is about the diameter of an acupuncture needle except that it has burrs to drill with. To handle these I use some sharp pointed tweezers with a locking collar of the sort that jewelers use to hold gemstones for inspection. I'm pretty good with my hands but it's difficult to dump out the little tube of the thinnest size bits and pick one bit out of it without dumping some of them.SO NOTE: the metric conversions given for the drill bit sizes appear to be inaccurate or maybe I should just say wrong. 0.013" is actually more like 0.33mm, and my micrometer read 0.013". So it would seem that the accurate numbers listed are the English units, not the metric ones. Therefore refer to the English numbers given and convert them to metric manually if you want to know the real diameters in mm.It's difficult if not impossible to get the really small bits perfectly centered in the pin vise, though using tweezers helps. I haven't really used a little pin vise like this before so I can't really say if this is typical, at least in this price range, or not. But to get the bits centered you might want to spend a little time adjusting them to be as centered as possible so they don't break.Notice that if you remove the nut from the pin vise you can remove the chuck, flip it around, and stick it back in the handle. This gives you a wider chuck capable of holding the larger sized bits. The nut was lubricated reasonably well as it was, but I added a bit of silicone grease to the threads and around the chuck which improved things a bit.I also carefully placed the smallest bit (0.013") in my  Dremel 8000  which was installed in a  Dremel 220-01 Rotary Tool Work Station  (which is basically a Dremel drill press attachment) using the regular  Dremel 4486 Chuck . I think I actually had an easier time centering the bit in the Dremel chuck than I did with the pin vise even though the dremel was locked into it's drill press attachment. I put the Dremel on its highest speed of about 35,000RPM and used it to drill several holes into a little patch of aluminum that I cut out of the side of a soda can. It went right through with no trouble.So I can't say for sure how well they'll hold up long term, but they look good. I just wish the pin vise did a bit better of a job helping you get small bits centered in the chuck, and it might be nice if it had a compartment in the handle for the bits. But the set comes with a nice tubular plastic box for the bits which is nice though a little less space efficient than it could be.Random related tip: For drilling small holes you can also use really thin sewing needles. Obviously they don't have the burrs for drilling, but they work for really thin soft sheets of metal like soda can foil. They work even better if you place the needle into a HSRT like a Dremel and turn it up to 30,000RPM, but I wouldn't exactly try to drill through stainless steel or anything 1" thick with such a thing. Unlike drill bits though I can put a needle in the Dremel and grind it against a sharpening stone or fine sandpaper to get it the exact diameter I want, and they're so cheap that if I ruin one it's not a huge financial loss.

Great set for the money! Seems to be durable and would definitely recommend!

I bought this to drill holes in baked (cured) polymer clay beads, pendants, etc., and it does the job, even on items that have been coated with a UV resin that’s been cured. I was aware, from other reviews, that the drill bits weren’t labeled with their size; I use a drill gauge to figure out the size of a given bit. I do think it wouldn’t have been difficult to label the drill bit sizes on the little plastic tubes in which the drill bits are stored within the larger case.What’s actually more difficult is figuring out which chuck (out of 4, since the 2 pieces are double-ended) to use with a given drill bit. Just looking at a chuck doesn’t tell you how much it will narrow down when screwed into the pin vise with a drill bit inserted (although one is obviously larger than the others).Because this is a hand drill, I do wish that the manufacturer had paid a little more attention to ergonomics. While the part of the drill you hold between your fingers is knurled and thus non-slip, it would have been better to have a rubberized coating for greater comfort. And the end that sits in the palm isn’t rounded (such as, say, being a hemisphere, which would be more comfortable); it’s actually hexagonal on the edges with a circular depression on the surface.I can’t give an opinion on durability, as I just received this yesterday.

I needed fine drills to drill through a steel ruler to make small circular punches. I did not use the hand-drill that comes with the set, only the drill bits in a Dremel tool and regular machine oil for lubrication.To my pleasant surprise most drills went through the steel just fine. Two of them however did not "bite", but when I exchanged them with spare bits from the same set those worked. So, the quality of the bits is not uniform - expect some duds. One 1.75mm bit burned out when I used it to enlarge a smaller pilot hole. I tried even the smallest bit (0.3 mm) just for fun. It flexed and snapped but that is not too surprising and it was not essential for my project. I am sure it would have done a fine job with softer material and gentler drilling.Overall I am pleased with my purchase because it allowed me to to accomplish what I set out to do.

Liked the pin vise felt good and solid. Did not like the bit selection. Instead of a good variety of bits it was three or four of the same size bits none of which where used for what I needed, but maybe I'll need them in the future.

Not fancy, but well made. It has 2 two-sided collets which are blued, or have black anti-rust coating on them. One goes in the "chuck". To get to the other one to switch them out you have to unscrew the handle on the other end. The spinning cap is held on with a "C" spring and works well, but not like smooth bearings. The smallest collet held a #73 bit right in the center (0.024" / 0.61mm - the size of a medium stick pin - bought separately, but it comes with smaller). If the "jaws" were longer inside so that it held more of the bit it would be better, but it worked. It should hold fine for larger bits. The machining is accurate. It's not an ultra fine finish, but there were no burrs anywhere, and it's good for the price. I'm glad I got it because it comes with a nice assortment of bits, the case works well for storage and has room for more bits, the collets are well made, and it can double as a regular pin vise.