Please read all the instructions and gather the materials and tools required.
Materials for eight foot long Picnic Table
||8'||The lumber must not be split or warped.
You may wish to use pressure treated lumber.1
A few extra boards may come in handy just in case.
|abt. 70 ||Ardox Nails
||3" ||Use double-dipped-galvanized to resist rust.1
|abt. 60 ||Ardox Nails
||2½" ||Use double-dipped-galvanized to resist rust.1
|8 ||Carriage Bolts
||3½ to 3¾" ||to fasten legs.2
|| ||to fit carriage bolts.
|| ||to fit carriage bolts.
|1 can ||Exterior paint or
|1 The manufacturers of some new pressure treated wood products
specify that single coat galvanized fasteners are
not compatible with the new generation of pressure treated wood.
They specify the use of ceramic coated fasteners, Hot-Dip Galvanized, double dipped,
or Stainless Steel fasteners depending on the harshness of the environment;
and that no aluminium be in direct contact with certain pressure treated wood products.
So if you use pressure treated wood, please check the manufacturer's recommendations.
2 Carriage bolts are the ones with a round head and a square neck.
The ones shown here are from a very old picnic table that was rebuilt.
To resist rust you will probably want to get galvanized carriage bolts.
These ones have a thread length of 1⅛", and you will not need the fully threaded kind.
They are ⅜" diameter, and 3½" in length, with NC16 threads.
This length will work if you first hammer the square neck into the wood far enough
for the washer & nut to fit on the other end.
Tools required: Tape measure, square, pencil, saw, drill,
hammer, sander, extension cord, string,
and something to tighten the nuts with,
such as a nut driver or socket set or wrench or pliers.
Set aside the 9 best looking 2x4's for the table top.
And set aside 6 strong 2x4's for the seats (that is 3 for each seat).
On the bottom of each of these 15 pieces, mark 12" from the end. This is
how far the ends will overhang the supports.
Cut the lengths of wood with the angles shown here.
Lengths shown in the Length column are the overall total length of each piece.
Angles are shown as a distance from the end of the board for convenience.
So all you do is this:
- measure from the end of the 2x4 and mark the distance (shown in the angle column).
and draw a diagonal from there to the corner.
- measure the overall length required.
- from there measure back the same angle distance and mark the diagonal.
- make sure the orientation of the two diagonals is correct for the piece
you are making. Most angles are marked on the wide edge of the 2x4
and cut from one narrow edge to the other (e.g. legs, seat supports, and table supports).
But angles on the cleats and end braces are marked on the narrow edge of the 2x4
and they cut from one wide edge to the other.
Also, most of the cut pieces are
trapezoids, but the legs and end braces are parallelograms.
- When you are sure, cut along the diagonals.
||Legs (parallelogram: cut leg angles from opposite edges of board)
||Table supports (beneath the ends of the table)
||Seat supports (across the end
of the unit from one seat to the other)
||Table cleat (cut cleat angles to the wide edge to lay flat under
the center of the table top. It ties the 9 long 2x4's
||Seat cleats (cut cleat angles to the wide edge to lay flat. Seat
cleats lay flat
under the center of the seats to tie the 3 long 2x4's together)
||End braces - The two diagonal pieces under the table.
(parallelogram: from beneath the middle of the table
to the inside edge of the seat supports) Here is the top and edge view of an end brace.
Optional: If you like to paint things before they are assembled, go ahead.
The two table supports are the 33½" pieces. The long edge is the top.
On the top edge of both table supports draw a mark 3¾" from each end,
that is where the legs will line up.
The seat supports are the 62½" pieces.
On the top (long) edge of both seat supports draw marks at these distances from each end:
3", 3¼", 6¾", 7", 10½".
These marks show where the 6 seat boards will go.
(The outermost two seat boards will overhang the ends of the seat supports by ½",
and there are ¼" gaps between them.)
The 10½" mark also shows where the legs will line up.
Find an empty space along a wall to line things up.
Lay one 62½" seat support flat on the floor parallel to the wall 12½" from it,
with the short edge toward the wall. The top of the seat support will be 16" from the wall.
Lay one 33½" table support flat on the floor parallel to the wall 25¾" from it,
also with the short edge toward the wall. The top edge is 29¼" from the wall.
Position two table legs over those two boards with the outer edge of each leg on the marks
at 10½" and 3¾".
Once you have the table support centered and the legs in position,
measure from corner to corner to verify.
From the foot to the end of the table support will be around 55".
The important part is for the two diagonal measurements to be equal.
Likewise the diagonals from foot to seat support ends must match each other.
Also the 10½" of seat support extending past each leg
is needed to fit the seat boards on later.
Mark the positions of the boards (on each board, draw lines where the other boards cross it).
Drill holes for the carriage bolts, in the center of each of the four joints, as shown here.
The carriage bolts go through the horizontal boards first then the legs.
The washer and nut go on the leg side of the joint.
(That way the smooth end of the carriage bolts will be at the outer side of the finished table.)
Assemble with bolts washers and nuts (fairly snug but not too tight at this time).
Lay the end unit back down flat with the washers and nuts on the top side.
Recheck diagonal measurements and make a final adjustment if necessary.
When the length of the diagonals match (from each foot to the opposite table support corner),
tighten down the nuts and nail the joints.
Put 3 or 4 nails in each joint.
Assemble the other end the same way.
See if you can get a couple of helpers for this part to hold the end units up.
Stand up the end units. The legs should be facing together. The outer sides
are the sides with the table supports & seat supports.
Lay the 6 seat boards where they go, 3 for each seat, with the nice side up.
Line up seat boards with 12" of each board overhanging past the seat supports at the ends,
and a ½" overhang for the back of the seat (that is, the back edge of the two outer 2x4's ½"
past the end of the seat supports). There should be ¼" gap between
2x4's. Nail them on with the 3" nails.
Lay the 9 table top boards where they go, with the nice side up.
Line up the 9 top 2x4's with 12" overhang at each end. Spread them out
about ⅜" between them. The 2 outer 2x4's should be about ½" past the
ends of the table supports. Mark where they go, as the hammering will shake
them around. Line up each 2x4 to its mark as you nail it down.
Turn the table over.
A seat cleat lays flat (not on edge) under the middle of each seat.
It ties the 3 long boards together in the middle.
Nail the seat cleats to the center of each seat with 2½" nails.
Nail the table cleat to the center of the table top with 2½" nails.
Nail on the end braces. They go from under the center of the
table to the middle of the end units.
Check for any exposed nail points, and hammer them over so they will not
catch or scratch anyone.
Optional: draw a curve at each end of the seats and table using a string,
nail, and pencil as a big compass. Then cut out the curved ends like this.
Sand the rough edges.
Apply finish as desired. (if you prefinished the parts, then just do the
touch-up paint now.)