Altering the primary bevels on a bevel up plane will dramatically alter the effective cutting angle. This can help to dramatically decrease tearout in even the most troublesome woods.
The combination of the blade’s bevel angle and the plane’s bed angle equals the effective cutting angle or pitch (I think I messed this terms up in the episode).
For most Bevel Up planes the pitch equals 37 degrees – this is the bed angle of 12 degrees along with the typical 25 degree bevel of the blade. This works fine for most end grains and softwoods. But for straight grained moderate hardwoods like Cherry or Poplar, a 50 degree pitched blade will give great looking results. For difficult grained woods a steeper pitched blade works even better.
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