Festool MFS Fence System Instruction Manual page 32

want to find pairs where the difference
in diameter between the bushing and
the ring is twice the diameter of the
router bit itself.
These pairs will cut female recesses of
any shape with matching males that fit
into those recesses which will be
smaller than the template by a known
amount, which I refer to as the "off-
set."
The offset from the side of the tem-
plate to the edge of the inlay is half the
diameter of the largest bushing or ring
plus half the diameter of the bit.
If you are starting with a male shape
that you want to fit into a female re-
cess, the template needs to be larger
than the male by this offset amount. If
you are starting with a female shape
that you want to cut a male to fit you
will wind up with a female recess and
matching male that fits that is smaller
than the original female by the offset
amount.
As you begin to explore the fascinating
world of template and pattern routing it is
very important to understand these rela-
tionships. I know it seems a bit confusing
at first, but hang in there and it will slowly
begin to sink in.
Let's take a look at the very capable met-
ric set from Festool. It is not a regular
catalog item but was developed for the
flooring installers who needed to do vari-
ous kinds of fancy inlays in their floors.
This is the metric set shown at the bottom
of the previous page. It only fits the 1000
and 1010 routers, not the 1400. There
are lots of inch sets available that fit the
universal guide bushing adapter for the
1400 from a variety of manufacturers.
32
The guide bushing on the Festool set
shown has a diameter of 10.6mm. There
are five rings marked, in increasing di-
ameter 4, 6-4, 8s, 6 and 8l. You can use
a 4, 6 or 8mm bit. With a 4mm bit you
can get male/female matching pairs with
various offsets by using the bushing
alone with ring 4, ring 4 with ring 8s and
ring 8s with ring 8l. Likewise you can use
a 6mm bit and get matching pairs with the
guide bushing and ring 6-4 or with ring 6-
4 and ring 8l. With an 8mm bit the com-
binations are guide bushing and ring 8s
or ring 4 and ring 8l. Each produces a
different offset so you can select which
best fits your situation. See the table in
Appendix B for details.
I like the metric set for use with the MFS
profiles since they are both denominated
in metric sizes so the math is easy.
The inch denominated set shown in com-
bination with the 1400 universal guide
bushing adapter is designed to work with
1/8", 1/4", 3/8", 1/2" and 3/4" bits. You
can probably find others as well.
If using the 3/4" bit, bushing and ring set
the bushing diameter is 7/8" and the ring
diameter is 2 3/8" so the offset is going to
be 3/8" plus 1 3/16" or 1 9/16". You cut
the female recess with the 2 3/8" diame-
ter ring installed and the male with just
the 7/8" diameter of the guide bushing so
the male will just fit into the female re-
cess.
These snap on guide bushing sets pro-
duce the same outcome as using two dif-
ferent guide bushings but are a bit faster
to use with the 1010 and most other rout-
ers since you don't need to change guide
bushings. With the 1400, changing guide
bushings is so fast that it is a toss up, but
the range of available sizes is limited.