What is the recommended bit speed for flat bits? I am sure that the speed varies by bit diameter and wood species
We have a recommended turning speed of 1500 - 2000 RPM on the IRWIN Speedbor wood boring bits, never exceed 2500 RPM. A good rule of thumb to follow on any drilling tool is the larger the bit the slower the speed. I'd recommend the 1/4" at a max 2000 RPM and slow the speed gradually as you move up to the 1-1/2" size.