This episode shows how I made a concrete fire pit out of Quikrete 5000; it takes about 20 hours and $120. I used my X-Carve CNC machine from Inventables to make reusable forms out of plywood. I created a modular design that includes embedded firebricks. I like this fire pit design because it is modular and can be relocated. This ability to move it in pieces makes it a great fire pit option for renters.