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CONTINUED - WOODWORKS: ADVANCED pROjECT 2009-2010 pATIO TABLE
beFORe yOu beGin
Good craftsmanship begins and ends with good work habits, so make
the following steps part of your routine workshop practice. If you have
any doubts or questions about how to proceed with a project, always
discuss them with your shop instructor.
• Carefully and fully review plans and instructions before putting a
tool to the project lumber.
• Work sensibly and safely. Wear safety goggles when doing work
that creates flying chips and sawdust; wear the appropriate
respirator whenever making sawdust or working with thinners
or other solvents.
• At the end of every work session, clean up your shop area and put
away all portable tools.
cuttinG AnD ASSeMbly
pROceDuRe
Make the Pattern Board
1.
The best way to deal with the geometry and joinery of the tabletop
is to draw it out full-size on a 4x4' piece of 3/4" MDF or other sheet
stock (see Fig. 2).
Build the Outer Ring
2.
Measure the length (long point to long point) of a section of the
outermost ring (A) on the pattern board. The measurement should be
at or close to 11-15/16".
3.
Using a sled (see Fig. 3) cut a 15° angle on one end of all the ring
segments. Then add a stop block and cut all the segment pieces to
final length.
4.
Dry-fit the segments on the pattern board to assure all the miters
are tight. You may have to adjust the angle of the last miter. If you do,
mark the joint so it can be reassembled correctly.
5.
After the dry-fitting, cut the slots for the spline joints into the mitered
ends of each outer ring segment on a router table. Cut splines (L) to
fit the slots.
6.
Add backer blocks to support the inside edge of the outer ring
(see Fig. 4).
7.
Cut the cam locks on the drill press using a 2-1/2"-dia. hole saw
with the drilling stock angled at 10º (see Fig.5).
8.
Screw the cam locks onto the pattern board so the short radius is
just shy of the spacer. The sacrificial spacers keep the cam locks from
being cut as the ring is routed out in the following steps (see Fig. 6).
9.
Glue up the outer ring (see Fig 4).
Rout the Outer Ring
10.
Screw a 1"-thick pivot block on the center of the pattern board.
11.
Make the trammel shown in Fig. 7.
12.
Chuck a 1/4" upcut spiral bit in your router and attach it to the
trammel. Set the bit to cut 3/16" deep. Hook the trammel on the pivot
block using the 22-1/8" hole. Turn the router on and plunge the bit
into the ring. Swing the trammel slowly around (see Fig. 8). Drop the
carriage another 3/16" and make a second pass. Repeat until there’s
about 1/4" of material at the bottom of the ring.
Important:
Don’t
cut all the way through the ring. You need enough material so the cam
clamps can continue to hold the ring in place.
13.
Hook the trammel on the pivot block using the 18-7/8" hole and
cut the inside edge of the ring in the same manner as the outer edge.
14.
Remove the ring from the pattern board. Use a jig saw to remove
the remaining stock from the ring. Don’t try to flush-cut the edges but
leave a slight tab.
15.
Remove the tabs with a flush trim router bit.
16.
Rout a 1/4" x 1/2"-deep groove all the way around the inside edge
of the ring, centered on the thickness.
Make the Tapered Slats
17.
Cut the table slats (B) to length.
18.
Using the slat taper sled (see Fig. 3), cut a 15° angle on one edge
of each of the slat pieces. Add the stop block to the sled and cut the
opposite edge to make the slats the correct size.
19.
Secure a slat on the pattern board for routing. Install a 3/4"
straight bit in the router. Set the trammel on the pivot point through
the 19-3/8" hole (see Fig. 9). The illustration shows the inner rabbet
being cut. Swing the trammel to make the first tongue cut. Then flip
the slat over and make the second cut to complete the tongue. It’s best
to start with a shallow depth of cut and gradually increase the depth
until the tongue is a perfect fit. Check the tongue’s fit in the ring’s
groove and make any necessary adjustments. Then rout tongues on
all the slats.
20.
Shape the tongue with a sander to match the arc of the shoulder.
21.
Cut the rabbet for the half-lap joint on the narrow end of the slat
with the trammel set in the 3-7/8" hole (see Fig. 9). Make sure the
slat’s good face is up for this step.
22.
Dry-assemble the slats in the outer ring and measure the exact
diameter of the center hub.
Make the Center Hub
23.
Cut and miter the four hub sections (C). Rout slots for splines
and epoxy the hub blank together.
24.
Draw a circle that matches the hub diameter. Cut the circle on
the band saw and sand smooth.
25.
Rabbet the underside of the hub (see Fig. 10) so the hub nestles
into the recess created by the slat rabbets. Don’t cut the hole in the
center of the hub yet.
