Diamond Drill Bit Set, 30pcs, 1mm 2mm 3mm (1/8")

I needed to drill holes in some shark teeth...like most normal folks do on a daily basis, of course. In particular, I wanted small holes just large enough for wax thread. So, I found these bits and thought I'd give them a shot. I had no illusions that these would be heavy duty for the price and just hoped that a set of thirty bits would be enough to drill 14 holes. Well, I have to say that I'm impressed. Not only did they work...But, I drilled all 14 holes in fossil shark teeth using just one bit. So, after reading all the other reviews, this was far better performance than I'd expected. Here's how I did it. 1. I found a small round tin with 2" high walls to use to hold the water and base for drilling. 2. I packed some Plasticine modeling clay into the bottom to act as a grip to hold the tooth. 3. I embedded the tooth into the clay and put enough water to cover the tooth by about a half inch. 4. I put the bit in my Dremel and set it to one of the lowest speeds. This is important because I think a lot of people are running these too fast and burning the grit off. 5. I slowly drilled into the tooth and frequently backed out to allow the filings to wash out of the hole and to cool the bit. I think it took less than an hour to drill 14 holes through shark teeth around 1/8 to 3/16" thick. That is the pro...definitely worth the money. The downside - Don't expect all the bits to be drill worthy. I mean, if you are drilling any sort of precision holes, only half of the bit tips are true enough for accuracy. The rest are fine for grinding edges or maybe enlarging holes. Some are slightly bent and some are varying diameters...just not precision manufacture. So, don't expect anything amazing for ten bucks. But, I'd definitely recommend them.

I got these to sand paint out of some very small corners, and they did the job. The only caveat is that the extremely thin metal warps a bit when when dremel gets going, and the tip makes a circle around an axis instead of spinning right on the axis. Once the tip was on the metal, i could press it into staying in place, but because of the extra pressure i also got a couple of unwanted grooves. Once I had a feel for how they needed to be handled though, they were wonderful for fine detail work.

Excellent!

Best diamond drills I've ever used. I've tried other suppliers and their drills don't hold up and only a few will bottom cut at all. Oudtinx 30 pack are the best I've ever used. I will buy them again. Fast shipping and just a wonderful drill. I drill Obsidian, Agate, and Jade. Mohs scale of 6.0 - 7.5 hardness.

Kind of cheaply. They are from China. Not that all products from China are bad but some are. This is an example. China! I know you can do better.

I don't know what happened to this product. Ive bought in the past. This time they are terrible! The tips break off within a minute of use. Don't think ill order this brand again. Very disappointed!

This item arrived first out of many. Super fast shipping!! These are the best inexpensive bits I have seen. The coating veries in thicknesses but there ready to do do the job!, Straight and well built at there core.. ( there not a blob of crap on a stick ) They all have threads where the metal/diamond was bonded, some are thick some are thin with the coating but way better than the cheap ones!... If you noticed in the pic the larger 3mm one's are machined down to Allow the 3mm shank to compensate for threads and a thick diamond coating for a final 3mm. That's why I ordered them and that's what I received.. I inspected each one with a loop and am very satisfied with this product for the price.

I must be using them wrong as I was only able to drill one hole through glass!

Work good

These bits are smaller than I expected but fit fine in my Dremel. It's nice that there are 2 sets. They work for my purposes in helping to shape small pieces of glass to use in mosaics. I am not sure how long the diamond grit will last but there are so many bits I am sure it won't really matter.

They are not good drill bits. Not good for drilling glass, came apart, like paper when it is wet. Would not go through glass, when my dremel drill was on a high speed. Would not recommend.

Value

Low quality .they wear out pretty fast .u get what u pay for .