Router bit brand selection

chip load is a science unto itself and it`s really the one relevent factor that affects all cutters whether it`s a routerbit, shaper cutter or drill bit....
how about expanding on the subject?
thanks! tod


It's a little complicated to fully explain here but the basics are that the chip load is important for surface finish and tool life. Larger chips are better at dissipating heat (which is an major enemy of carbide) but conversely a chip that is too large will result in a rough finish. The proper chip thickness varies with the material but a good rule of thumb would be 0.1mm to 0.2mm (0.004" to 0.008"). To determine the chip size without trying to measure tiny bits of sawdust you can calculate with this formula:
Chip Load = Feed Rate (ipm) / (RPM X Number of Flutes)
Bits and Cutters for CNC or power feed operations are very specific to the material being cut and the intended feed rate (to maintain productivity). For router bits and cutters designed for the woodworking markets many compromises are made because making application specific bits would be confusing and cost prohibitive. But following the manufacturer's guidelines for recommended RPMs should work well for most hand feed operations.

tod evans

thanks charles!
i`ve found that in handheld routers bits seem to last longer if i push the motor `till it grunts and back off a`s that for science?:eek:
cutting slowly will definately shorten bit life..