Review on Durable Diamond Drill Bits for 💎 Precise Drilling - Bastex Diamond Drill Bit Pieces by Andrew Frison

I bought these to drill holes in marble tiles as well as glass. They work as expected. I always use a drill as there is nothing to guide the drill. So if you try using a hand drill, be prepared for a character-building experience. Also, be sure to drill with light pressure on the end to minimize backing pop-out. On the other hand, if you don't have a drilling method (fences, jugs, etc.), I found it difficult, but not impossible, to get rid of most of the protrusions on the back. Personally, I nearly drilled through, flipped the part, brushed the dirt off the back, and then cleaned the edges. In most cases minimal slip was not really a problem. These are not heavy drills and I don't expect long life: they are what I paid for and they did their job admirably. If they fail, they're cheap enough to replace.