Japanese Saw Horse Weekend Build

Building a pair of Japanese-style saw horses over a weekend.

Plans

These free plans build one saw horse from two 8 ft 4x4s. Build two for a pair. The parts join with mortise and tenon joints, with no screws.

Saw horse parts lined up for assembly: top, support rail, leg, and foot

The finished saw horse is 42” long, 22” deep, and 32” tall.

Cut list

All parts are 4x4 (3 1/2” × 3 1/2”).

Part Qty Length Joinery
Top 1 42” 2 mortises
Support rail 1 38” 1 tenon at each end
Leg 2 32” 1 tenon at each end, 1 mortise
Foot 2 22” 1 mortise

Cutting the lumber

Cut the six parts from two 8 ft 4x4s:

  • Board 1: foot (22”), leg (32”), and support rail (38”). This leaves about 4” spare.
  • Board 2: foot (22”), leg (32”), and top (42”). These parts use the full 96”.

Board 2 has no room for saw kerf. Measure your board first; many 8 ft boards run a little long. If yours is exactly 96”, cut the top last and accept a slightly shorter top.

Cutting diagram: two 96-inch 4x4s, one cut into foot, leg, and support rail, the other into foot, leg, and top

Joinery

Every tenon and mortise is 3 1/2” wide and 1 3/16” thick. Each tenon is 3 1/2” long, the full thickness of a 4x4, so every mortise goes all the way through.

  • Leg: cut a centered tenon on each end. The two tenons turn 90° to each other: the top tenon lines up with the top, and the bottom tenon lines up with the foot. The 25” between the shoulders sets the height. Cut one mortise through the side, centered on the length, for the support rail.
  • Support rail: cut a centered tenon on each end. The shoulders are 31” apart.
  • Top: cut two mortises down through the top, each starting 4” from an end and centered across the width.
  • Foot: cut one mortise, centered on the length and across the width.

Exploded view with joinery sizes: 3.5-inch tenons and mortises, 1.2-inch tenon thickness, top mortises 4 inches from each end

Assembly

  1. Push the support rail’s tenons through the mortises in the two legs.
  2. Set each leg’s bottom tenon into a foot.
  3. Lower the top onto the legs’ top tenons.