18
OPERATION
EDGING WITH PILOTS
See Figure 15.
You can cut rabbets and molded edges using piloted
cutters. The pilot, which extends below the cutter, allows
the cutter to turn while the pilot follows the edge of the
workpiece. Some pilots are solid extensions of the cutter.
Others are ball bearing guides that are fastened to the
end of the cutter.
Arbor-type bits with pilots are excellent for quick, easy
edge shaping. They follow workpiece edges that are
either straight or curved. The pilot prevents the bit from
making too deep a cut. Holding the pilot firmly in contact
with the workpiece edge throughout the cut prevents the
cut from becoming too shallow.
Whenever the workpiece thickness together with the
desired depth of cut (as adjusted by router depth setting)
are such that only the top part of the edge is to be
shaped (leaving at least a 1/16 inch [1.6 mm] thick uncut
portion at bottom), the pilot can ride against the uncut
portion, which serves to guide it. However, if the
workpiece is too thin or the bit is set so low that there will
be no uncut edge to ride the pilot against, an extra board
must be placed under the workpiece to act as a guide.
This guide board must have exactly the same contour —
straight or curved — as the workpiece edge. If the guide
is positioned so that its edge is flush with the workpiece
edge, the bit will make a full cut (in as far as the bit
radius). On the other hand, if the guide is positioned as
shown (out from the workpiece edge), the bit will make
less than a full cut — which will alter the shape of the
finished edge.
NOTE:
When edge shaping with guides, you can use any
of the piloted bits without a pilot. The size (diameter) of
the pilot determines the maximum cut width that you can
make with the pilot against the workpiece edge. The
small pilot exposes all of the bit; the large one reduces
this amount by 1/16 inch (1.6 mm).
When routing all edges of a panel or board, rout the end
grain first. Any splintering that occurs at the corners will
then be removed when routing the sides. Start each side
1/4 in. (6.35 mm) away from the end. Feed the cutter into
the wood until the pilot contacts the uncut edge. Then,
slowly back the router to shape the corner. Next, move
the router forward to shape the rest of the edge. Be
careful to keep the pilot pressed against the uncut edge.
Repeat this procedure on each side of the panel. Figure
20 shows the proper sequence of cuts to make when
edge routing four sides of a panel.
Fig. 15
PILOT
WORK
WORK
PILOT
TOP EDGE SHAPING
WHOLE EDGE SHAPING
GUIDE
ROUTER
ROUTER
