50pcs PCB Drill Bits Set Spiral Flute Carbide 0.3mm-1.2mm for Print Circuit Board Stone Dremel Jewelry CNC Engraving (5pcs each)

Excellent for scale models!! These micro drill bits will work in any adjustable chuck hand drill. As some of the bits are oh so easy to break, at this price point it’s worth having extras on hand.

５ケース入りだったので購入。当たり前だが，細いドリルは作業中に余計な方向から力が加わったり，落としたりするとすぐに折れる。使ってすぐに折れた。慣れてくるとそれほどでもないが，慎重さは必要。特に０．４ｍｍ以下は折れに注意。それ以上の大きさはずっと使えそうな感じがする。５セットもあるので。

They do the job but as to be expected, the small (er) ones are super easy to break so yeah, the 5 pack is gonna come in REAL handy. It's not the tools fault it's the tool running the tool, I didn't have my drill bit square to the piece i was drilling a couple of times and they break easy. If you're using them square to you work piece and dont change the bits angle once you're in and allow the bit to pull itself through you will be amazing at what they can do

These arrived promptly. They appear to be good quality. Due to some feedback from similar listings for drill bits of this type I was keen to try them - especially the smaller bits. I mounted the smallest bit (0.3mm) into my micro-drill press and drilled multiple holes in 1mm ABS, 4mm soft timber and 1mm brass sheet. Whamo - all good. No breakages. I tried two speeds. 50% (approx. 2000rpm) and 100% (approx. 4000rpm) All good. As mentioned umpteen times before on these sorts of listings, you need to go EASY with these types of bits - or any small bits like these. Any excessive run-out on your drill press or excessive force WILL snap the bit. Drop the quill a tiny bit at a time, back off a tad and drop it again. Repeat till the bit pops through. Even in a pin-vice any slight twist or bending will likely snap anything under say 0.5mm. So go easy, give these bits the due attention they require and they will last you. Lastly, if you use small bits often - it's really a good idea to invest in a micro drill press (if you have a good look around you don't need to pay a lot of money for one 😉). 😎 Edited 22/06/2025 - corrected drill speeds.

スルーホール基板の修正に使いました。思い通りの作業が迅速に出来て大変助かりました。なお、ビットサイズの別が分かり易い様に、プラスチック製の色分けされたリングが付いていて助かるのですが、出来れば、この色分けを、小数点以下の数値に合わせ、電気で使うカラーコードに倣い、小数点以下の数値が、1は茶色、2は赤、3は橙、4は黄色、5は緑、6は青、7は紫、8は灰色、9は白、0は黒と言うような、色分けにすれば良いと思います。整数の位の径の違いは、見ればわかりますし、小数点以下の色分けで、例えば、隣り合わせの、茶と赤、赤と橙を間違えて使用してしまっても、多くの場合、製作物が駄目になることは無いと思います。こんな色分けだったら、この商品は最高ですね。