A QuiltPlan piecing reference
V-Block
the fold-and-trim method: no specialty ruler needed
A V-Block is a single triangle centered in a square, background fabric filling the two top corners: the same unit that forms the points of a Sawtooth Star. You can cut it with specialty rulers, or fold, cut, sew, and trim your way there with just a rotary cutter.
Starting triangle square: finished size + 1″.
Trim-to (unfinished) size: finished size + ½″.
Side trim, measured from the center crease: half the trim-to size.
Top trim, from the point: a constant ¼″, the same at every size.
Fold & press
Fold the colored square in half (edge to edge), and press to crease. It's now doubled: two layers.
Cut the diagonal
Still folded, cut once corner to corner through both layers. Keep the folded piece. Discard the loose scrap triangle.
Unfold: your triangle
One triangle: base and height both equal the original square's side. Keep that center crease visible. You'll trim from it later.
Position the background
Folded in, right sides together, mostly covering the triangle, edge flush with the slant. The dashed line is the seam, a scant ¼″ in from that edge.
Sew & press open
Sew both seams, then press the background pieces flat and open. The two pieces overlap above the point. That line is normal.
Mark & trim
Trim ¼″ above the triangle's point, then trim each side to the chart's side-trim measurement from the crease, then trim the bottom to the trim-to size.
Result
One clean V-Block unit. Rotate it any direction when you assemble a Sawtooth Star or similar block.
| Finished | Start sq. | Trim-to | Side trim |
|---|---|---|---|
| 2″ | 3″ | 2½″ | 1¼″ |
| 2½″ | 3½″ | 3″ | 1½″ |
| 3″ | 4″ | 3½″ | 1¾″ |
| 3½″ | 4½″ | 4″ | 2″ |
| Finished | Start sq. | Trim-to | Side trim |
|---|---|---|---|
| 4″ | 5″ | 4½″ | 2¼″ |
| 4½″ | 5½″ | 5″ | 2½″ |
| 5″ | 6″ | 5½″ | 2¾″ |
| 6″ | 7″ | 6½″ | 3¼″ |
Background rectangles: cut them generous, about 1″ longer than your starting square and roughly two-thirds the trim-to size in width, then trim away the excess in step 6. A little extra fabric is always safe here; a little short isn't.
Prefer templates? A Tri + Recs ruler set cuts this same unit without any folding.
Built from V-Block units
Dogwood
Fight
Minnesota Block
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