Speed Square Tricks

The protractor, layout gauges, and scribe notches hiding on a rafter square.

2 takes from different creators

Ten Jobs One Speed Square Does on a Framing Site

Beyond marking a 90 and a 45: the speed square marks any angle from its pivot, gauges parallel rip lines, finds center fast (angle the square so an even number spans the board and mark half), squares off any existing line, guides the saw as a cutting fence, and — with stair gauges clamped on — repeats a rafter's pitch cut after cut.

speed square uses list, find center of board fast, stair gauges rafter cuts, speed square rip guide, mark angle without protractor

beginner Tools: speed square, stair gauges Added Aug 6, 2026
Watch the instagram video by @builtright_co (opens in new tab)

The Problem

The speed square rides in every pouch for 90s and 45s, and for most owners that's where it ends — while the same triangle replaces a protractor, a rip gauge, a center finder, and a rafter square.

The Techniques

  1. Mark a 90 off the fence — the everyday cut line.
  2. Mark a 45 off the hypotenuse.
  3. Mark any angle: hold the pivot corner on your line and swing the square until the degree scale reads the angle you want.
  4. Step off consecutive layout lines by walking the square down the board.
  5. Draw a line parallel to the edge: set a pencil in the scribe notch at your width and slide the square's fence along the board — a rip line the length of the stock.
  6. Find center: lay the square's rule across the board at an angle so an even number spans edge to edge, and mark half of it — on a 2x6, angle to 6 and mark at 3; on a 2x4, angle to 4 and mark at 2. No dividing 5-1/2 in your head.
  7. Square a line off any existing line, not just off an edge — the fence registers on your mark.
  8. Guide the saw: hold the square as a fence for the circular saw shoe on crosscuts.
  9. Repeat a rafter pitch with stair gauges: clamp the little gauges to the square at the pitch (the demo sets a common 4), and the square registers the same plumb cut on every rafter without re-measuring.
  10. Then use it as the cutting fence for that rafter cut, same as any crosscut.
Pro tip: The stair gauges are the sleeper accessory — a few dollars of knurled clamps that turn the square into a fixed template for any repeated angle, which is most of what a framing square's rafter tables get used for on a small roof.
Watch the instagram video by @builtright_co (opens in new tab)

Tom Silva's Speed Square Tricks: Protractor, Layout Gauge, and Scribe in One Tool

Beyond marking square lines: pivot it as a protractor to mark any angle, use the edge increments to offset jack studs, drag a pencil in the 3½-inch diamond to draw a plate line, and ride the scribe notches down a board for a rip line.

speed square hacks, what the markings mean, uses for a rafter square

beginner Tools: speed square Added Jul 25, 2026
Watch the instagram video by @tomsilvatoh (opens in new tab)

The Problem

Most speed squares live their whole lives marking 90s and 45s. The tool was designed as a rafter square, but it carries a protractor, a set of layout gauges, and a scribe — features stamped right on it that most owners have never used.

The Techniques

  1. Protractor for any angle. The lipped edge has a pivot point at the corner. Hold the lip tight to the board's edge, swing the square, and read the degree scale — stop at 22½ and your pencil line along the square's edge is 22½ degrees off the board edge.
  2. Square stud layout. Marking 16-inch centers, use the square to carry a true square line across the plate at each mark before X-ing the stud side — crooked layout lines become crooked walls.
  3. Offset marks for doubles and jacks. Along one edge the square carries marked increments — 1", 1½", 2" from the edge. Marking a jack stud beside a king? Slide the square to the 1½" mark and your line lands exactly one stud-thickness over.
  4. Draw a 3½-inch line with the diamond. The diamond cutout sits at 3½ inches — the width of a 2x4. Drop a pencil in the diamond, hold the square's lip tight to the board edge, and drag: a straight line exactly where a flat 2x4 would land.
  5. Scribe rip lines with the notches. The square's cutouts hold a pencil at set distances — put the pencil in the notch, slide the square down the board, and you've scribed a parallel rip line at 1", 1½", 2", wherever the notches sit.
Pro tip: The dragging tricks (diamond and notches) work because the lip registers the square against the board edge the whole way — keep sideways pressure on the lip as you slide and the line stays parallel; let it float and the line wanders.
Watch the instagram video by @tomsilvatoh (opens in new tab)

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