Diamond hole saw are used for brittle materials such as glass, ceramic, porcelain, granite, etc.
Pilot bits are usually not good for brittle material applications. They tend to make a crack before the hole saw starts working. The crack propagates and ruins the project.
Instead of a pilot bit, our DRILAX sets comes with a tough poly insert with can be used as a guide to hold the diamond hole saw steady.
You only need the insert for the few turns. You can continue free hand once the diamond hole saw makes the initial mark.
Or if you like, you can buy one of our DRILAX diamond hole saw guides.
These are adjustable.