INCRA Wonder Fence - Manual (Page 8)

Adding a zero clearance subfence to your Wonder Fence
is a perfect solution to providing tearout control and
additional support for your workpiece when using large
diameter cutters . Typically a zero clearance subfence
is a long piece of wood with the profile of a particular
cutter bandsawn into the face . When attached to the
router table fence and moved into position, the router
bit nestles into the cutout . This close fit around the
cutter provides the tearout control and support for
your workpiece,
Fig. 17 . Here’s how to prepare a zero
clearance subfence for your Wonder Fence:
Making a zero clearance subfence blank
Begin with one piece of 3 ⁄ 4 " medium density fiberboard
3 1 ⁄ 16 " x 32" . Layout the
drill and counterbore
centers as shown in Fig.-18,
then cut to the length as
shown . Drill and counterbore
at each center mark using the
dimensions in
Detail-18 .
8
Fig. 17
Zero clearance subfence
1
Fig. 18
Subfence dimensions
Detail 18
3 ⁄ 4 " dia. x 3 ⁄ 8 "deep counterbore
5 ⁄ 16 " dia. through hole 3 3 ⁄ 4
"
3 3 ⁄ 4
"
1 3 ⁄ 4
"
Fig. 19
Slot dimensions
Connect the through holes with a slot
In order to later access the fence offset adjustment
screws on your Wonder Fence, you’ll need to connect
the through holes on your zero clearance fence halves with a
slot . See
Fig 19 . Install a 5⁄16" straight bit in your router table
and set the depth of cut to 1⁄4" . Position your fence so that the
router bit will nestle into the through hole located at one end
of the subfence . Clamp a stop on your infeed fence against
the end of the zero clearance fence . Lift the zero clearance
fence off of the router and place the end of the zero clearance
fence against the stop . Now slowly lower the piece onto the
cutter . Slide the zero clearance fence forward until the router
bit is seen entering the rear hole . Slide the piece back to the
starting position and turn off the router .
2
Zero Clearance subfences
Fig. 20
Connect through
holes with slot
1 st Pass: 5 ⁄ 16 "diameter cutter, 1 ⁄ 4 depth of cut
2 nd Pass: 1 ⁄ 2 "depth of cut
3 rd Pass: 3 ⁄ 4 "depth of cut
Double face tape
holds scrap of
wood to stock for
use as handle
To make this cutting operation
safer, use double-faced tape to
attach a scrap block of wood to the
zero clearance fence . The scrap can be
used as a handle to safely raise and
lower the stock .
Repeat this cut for the other zero clearance
fence . Next, increase the depth of cut by
1 ⁄ 4 "
and repeat the cutting process for both pieces .
Finally raise the bit to cut completely through
the stock and repeat the cuts .
First: Turn on
router and lower
stock onto cutter
Second: Slide
stock forward.
Stop cut when
router bit is seen
entering rear hole.
Third: Slide stock
back to starting
position and turn
off router.
CauTIOn: The cutter will be cutting
through the top of the stock. Keep your
fingers clear of the line of cut.
(See TIP above and Fig. 20.)
15 1 ⁄ 2
"
15 1 ⁄ 2
"
8"
8"
5 ⁄ 16 " wide slot
connecting both 5 ⁄ 16 "
through holes