Reply by MrRon

Whatever bit you use, it is imperative that you clamp the work down with a sacrificial board top and bottom. Otherwise you will get tearout. Make sure the bit you use is very sharp. I would suggest a carbide tipped forstner bit. I’m assuming you are using a drill press, so keep the revs high. I’m not sure if they make brad point bits in 1” size; if so, that would work well.