Review on 🧱 Highly Durable Industrial Concrete Cinderblock for Masonry Projects by Frank Mayes

These can be used to pierce the bottom of two thick glass bottles. If they're bent, broken, or dull on you, you'll need to slow down and add some lube. I used some shear oil, but any friction reducer will do. For larger holes, it also helps to use smaller pilot bits so you don't wear out a bit as much. Take breaks to cool them down, they'll get hot.