Tried with oak and pine. This made an acceptable hole but was very slow and required a lot of pressure, causing the bit to heat up quickly. I considered sending it back but decided not to bother. The design is difficult to sharpen, and the Chinese sharpened it rather roughly. I cut a little better with an augur file and a ceramic shank from my triangular sharpener, but still not very well. I have an old Irwin bit of the same size, made in Austria. It's the exact same design and cuts just asβ¦