Flush Router Bit Diameters

[Holbren]

You have received good advice for flush trim bits where the bearing is the same diameter as the cutter. For pattern bits where the bearing is on the shank, the 1-1/8" bit has a more substantial bearing and less likely to fail. If you do the math on a 3/4" pattern bit with a 1/2" shank, there is only 1/8" of bearing width making it a delicate bearing.