You get tearout, even though the blade is sharp.
The chip breaker is set too far back, or the plane’s mouth is too large.
First, adjust the chip breaker closer to the end of the blade (photo,
below). Second, move the frog forward to close the plane’s mouth
In general, the finer the shaving you’re trying to cut, the closer
the chip breaker should be to the blade’s edge. A 1/32 in. setback is
ideal for most hardwoods, but when you get tearout, try moving the chip
breaker to within 1/64 in. or less of the blade’s end. This will make
the plane harder to push, however. (In soft woods, like pine, where
tearout isn’t an issue, you can adjust the chip breaker up to 1/16 in.
back from the blade to make the plane easier to push.)
To move the frog, remove the lever cap, blade and chip breaker.
Slightly loosen the two bolts that hold the frog to the sole. Reinstall
the blade assembly and adjust the blade until it barely sticks out of
the plane’s sole. Turn the frog adjusting screw with a long screwdriver
to close the plane’s mouth. Once you have created the desired opening,
remove the blade assembly and tighten the bolts that secure the frog.
Tighten each one a little bit at a time, like a car’s lug nuts.
Moving the frog may skew it, however. On most planes, you can only
eyeball the frog to make sure it’s front end remains parallel to the
plane’s mouth. Frogs on Stanley planes manufactured in the Sweetheart
Era, roughly 1920 to 1935, are self-aligning, so skewing isn’t a problem
Tip: Rub your plane's sole with a few squiggles of paraffin or
canning wax every ten strokes or so. This helps your plane glide much
This story originally appeared in American Woodworker July 2007, issue #129.
July 2007, issue #129
Purchase this back issue.
To reduce tearout, adjust the chip breaker closer to the blade’s
edge. A projection of 1/32 in. is normal for most hardwoods, but to beat
tearout you may have to go down to 1/64 in. or less.
To further reduce tearout, move the frog forward by turning the frog
adjusting screw. This closes the plane’s mouth. Normally, the mouth
should be about 1/16-in. wide. You can reduce it down to 1/64 in.
If you move the frog forward, you must double-check that it hasn’t
wiggled side-to-side and become skewed. Many older Stanley planes have
an alignment tab to prevent skewing, which is an excellent feature.