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Need more bench space? Who doesn’t? Here’s a terrific
solution: a folding worktable that’s both big and
strong.And we mean strong.
You can set it up in only a minute and be ready for
routing, sanding, planing—you name it. When
you’re done, fold up the table into a super-compact unit
only five-inches thick and stow it away. Here
today, tucked away tomorrow.
Strong = Heavy
This table weighs in at about 70 lbs., a
bit more than the full sheet of plywood
it’s made from.A lighter table made of
smaller plywood parts would be more
portable,but not stiff enough to use as
a real workbench (Photo 1). For heavyduty
use, extra weight is actually a plus.
This table stays put!
The keys to this table’s strength are
its wide rails, rigid continuous hinges
and hardwood legs. The oversize rails
and long hinges prevent the table from
racking. The solid-wood legs prevent
the plywood end panels from bending
or shaking.
Go ahead and shove this table
around the shop. The hardwood legs
can take the punishment. Folded up, it
stands on a durable hardwood rail, so
you can slide the table across the floor
into a small cubbyhole (Photo 2).
Tools and Materials
This is a low-cost, easily built plywood
project.Total cost is about $75, half
for the wood and half for the
hardware. You can build it in a day,
no sweat, using little more than a
tablesaw, jigsaw, hacksaw and a drill.
All you have to do is cut a few plywood
pieces to size, rip and cut some narrow
3/4-in.-hardwood boards to length
and accurately drive in a whole mess
of hinge screws. To make setting the
hinges a lot easier, we recommend
using a self-centering bit (see Sources below).
Build your table from one sheet of an
inexpensive grade of birch plywood
(about $40). Fir plywood and MDF are
even less expensive, but both are
inferior substitutes. Fir plywood is
usually quite twisted and MDF is way
too heavy.
You’ll need some 3/4-in. solid wood
for mounting the hinges. Plywood
won’t do, because the hinge screws run
into the edge of these boards. This
would place the screws between the
plies and chances are they wouldn’t
hold. Pine isn’t a great choice, either,
because it’s too soft to hold small screws
well. Go with a hardwood that’s milled
flat so you can glue its faces together.
Birch or red oak are good choices.
Pick up most of the hardware at a
hardware store or home center (see the
Shopping List). It’ll add up to about $35.A good chunk of that is for
the continuous hinges, but they’re worth
it. Standard butt hinges allow too much
play and the table would wobble.
The only hard-to-find items are the
large knobs on the rails.We used Tstyle
knobs because they offer a lot of
leverage and have a low profile (about
$2 each, see Sources). (Round
knobs won’t allow the table to fold
completely flat.)
Making the Plywood Parts
Begin by cutting up the entire sheet of
plywood (see Fig. B).Note in
the Cutting List, that End
Panels B and C differ in length by 3/4-
in. because they fold underneath
stacked blocks of different thicknesses.
Rails D and E require a bit more
tablesaw work.Cut grooves in both rails
for the threaded rod (Photo 3). You can use a dado set or make
multiple cuts with a standard blade.
Then create a flat surface for the T-style
knobs to bear against (Detail 1) with a crosscut on the tablesaw. Attach
a tall backer board to your miter gauge
and stand the rails on edge to make
these cuts perfectly straight and square.
Cut the arches in the rails with a jigsaw.
Keep the jigsaw handy. Cut three
clearance holes, one in the edge of Rail
E and two in End Panel B (Fig. A). The
holes allow all the parts of this table
to fold flat.
Making the Locking Bolts
Four stout bolts with T-handles lock
this table together.Cut the bolts to length
from threaded rod.Sitting in the groove,
with the handle attached, the bolts must
stick out about 5/8-in.beyond the end of
the rail (Detail 1).
Glue a T-handle onto each threaded
rod with epoxy or a special permanent
glue made for nuts and bolts, such as
Loctite or Thread Locker (available at
hardware and auto stores for about
$2.50 a tube).Heavily round the other
end of the bolt with a file or grinder so
it easily engages the T-nut.
Place the bolts and washers in the
rail’s grooves. The bolts are held in
place by small strips of hardwood cut to
fit the groove (Fillers J, Detail 1). Glue in the fillers. With a clamp
or two, squeeze down on the fillers so
they bite into the screw’s threads a bit.
When the glue is dry, the bolts shouldn’t
slide freely (or they’ll fall out when you
fold up the table!). Dab a little grease
onto the bolts to make them turn easier.
Cut and drill four plywood blocks to
receive T-nuts (Parts H, Detail 2).
Pound in the T-nuts and clear the deck
for assembling the table. All the parts
are now cut to size and ready to go.
Attach three of the hinges to three of
the six hardwood Riser Blocks F (Photo
4 and Detail 3).
Attach a hinge to Rail D as well (Detail
4). Toss the screws that
come with the continuous hinges.
They’re too short and fragile. Use the
larger screws included in the Shopping
List. Don’t bother to
countersink deeper holes in the hinges
for these screws.The heads don’t show,
so it’s not worth the trouble.
Assembly
Put the table together in three stages (Fig. C), upside
down, level by level. Test the parts as you go to make
sure they fold flat.
Screws alone do a surprisingly good job of aligning
the parts and holding this table together. Glue the
parts to make the table even stronger.
Step 1. Attach Spacer G1 to the underside of Top A.
Butt Rail D to the spacer and screw the hinge to Top A.
Screw Spacer G2 to the top. Butt one Riser Block F
with an attached hinge to the spacer and screw the riser
block to the top. Clamp Rail E to the hinge and screw
the hinge to the rail.
Step 2. Attach a Riser Block F (with no hinge
attached) flush with the left side of the table. Screw
another Riser Block F (with a hinge attached) on top
of it.Attach End Panel B to the hinge.
Thread two T-Nut Blocks H onto the bolts in Rail D
and Rail E. Be sure the T-nut faces out (Fig. A).
Screw the T-nut blocks onto the end panel (Photo 5).
Step 3. Attach the remaining two Riser Blocks F
(without hinges) flush with the right side of the table.
Stack the third riser block (with a hinge attached) on
top. Attach End Panel C to the hinge. Attach the T-nut
blocks the same as before.Glue on the Legs K1 and K2.
(Note that they go on the inside of Panel B and the
outside of Panel C; see Fig. A.) Glue on the Feet
L and attach the handle.
Once the table is assembled, round over all the
edges with sandpaper, a file, or better yet, a 3/16-in.
round-over bit in a router. To keep the table from
rocking on an uneven floor, insert 1/4-in.T-nuts and
bolts into the ends of the plywood panels as very
simple and easy-to-adjust levelers.
Source
Woodcraft,
woodcraft.com, 800-225-1153,
T-Style Knobs, 5/16"-18, #142226, $1.19 ea.; 7/64" Self-Centering Hinge Bit for #5 & #6 Screws, #16I41, $12.50.
Shopping List
Cutting List
This story originally appeared in American Woodworker April 2002, Issue #93.
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Click any image to see a larger version.
1. This worktable is built for
strength. It won’t wobble, sag
or walk across the floor. Weighing 70
pounds or so, it’s not going anywhere
until you stow it away.
2. This table is built like a rock but knocks down in only a minute. You don’t
need any tools and you don’t have to keep track of any loose pieces. Simply unscrew
four knobs, fold the rails and legs on top of each other and tuck the worktable away.
3. Cut one long groove in each rail to receive the four
pieces of threaded rod that hold the table together. Use
a tall fence and a featherboard to steady the workpiece.Then,
cut out an arch in the rail so your hands have room to turn the
knobs on the threaded rods.
4. Mount the hinges before assembling the table.
Positioning the hinges is critically important, but easy to
do. Simply fold a hinge over one of the hardwood riser blocks
and clamp it in place. Drill pilot holes with a self-centering bit.
Drive in the screws, unfold the hinge and you’re good to go.
5. Lock the table together with bolts and T-nuts. The T-nuts
are buried in wood blocks that are screwed to the table’s end
panels. Locating the blocks in exactly the right spot is easy.
Step 1. Thread the blocks onto the threaded rod buried in the rail.
Step 2. Swing the rail upright.Then drive a screw through the T-nut
block and into the end panel.
Step 3. Unthread the bolt from the T-nut block. Fold the rail down and
out of the way.Then drive in the bottom screw through the T-nut block.
Fig. A: Exploded View
Fig. A, Detail 1: End of Rails D and E
Fig. A, Detail 2: T-Nut Block H
4. Trim the face frame flush to the cabinet sides. Use a stop block at the top of the cabinet openings to prevent the router from cutting into the upper rail.
Fig. A, Detail 3: Location of Hinge on Rail E and End Panels of B and C
Fig. A, Detail 4: Location of Hinge on Rail D
Fig. B: Plywood Cutting Diagram
Fig. C: Three Assembly Steps
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