Shoofly Quilt Block — Cutting Chart for Any Size

2 fabrics · Difficulty 2 of 5

Shoofly is a 3×3 block of 13 pieces. Cut sizes for 6″, 9″, 12″, 15″, 18″ are below; for any other size it divides into cleanly, type the size and the chart recomputes.

Set the finished size

At a glance

Grid
3×3
Pieces you cut
9 — subcutting turns them into the 13 in the sewn block
Difficulty
2 of 5 — easy How this is scored

Set the size

Cutting sizes for a 12″ finished block.
Squares — Background
4½″
Squares — Fabric A
4½″
Squares for half-square triangles — Fabric A
4⅞″
Squares for half-square triangles — Background
4⅞″
Shoofly quilt blockA 3 by 3 grid of 9 units: 4 half-square-triangle units and 5 squares. 13 pieces in total.
Shoofly — a 3 by 3 grid of 9 units: 4 half-square-triangle units and 5 squares. 13 pieces in total.

Reading focusCorner triangles read outward from the centrehalf-square-triangle unit

Construction lattice
3 modules wide × 3 modules high
Unit mix
half-square-triangle unit, square
Piece count
9 to cut · 13 in the diagram

Cut these pieces

Column headings are the FINISHED block size — the size it will be once it is sewn. Every number in the table is the size to CUT, which includes ¼″ of seam allowance on each edge. Rows that are subcut on a diagonal are cut larger still, so the allowance survives the extra cuts.

Scroll sideways to see every size.

Cutting sizes for Shoofly, by finished block size
Patch6″9″12″15″18″
Squares — BackgroundCut 42½″3½″4½″5½″6½″
Squares — Fabric ACut 12½″3½″4½″5½″6½″
Squares for half-square triangles — Fabric ACut 2, cut once on the diagonal2⅞″3⅞″4⅞″5⅞″6⅞″
Squares for half-square triangles — BackgroundCut 2, cut once on the diagonal2⅞″3⅞″4⅞″5⅞″6⅞″

Read the block

Match each fabric letter in the diagram to the same fabric name in the cutting table. The caption describes the generated geometry in text.

Fabrics in this block

  • A — gold
  • BG — background

Which sizes divide cleanly

Scroll sideways to see every column.

Which finished sizes each grid divides into cleanly
GridDivides cleanly atThe first few sizes
2×2every 1″1″, 2″, 3″, 4″, 5″, 6″ …
3×3this blockevery 1½″1½″, 3″, 4½″, 6″, 7½″, 9″ …
4×4every 2″2″, 4″, 6″, 8″, 10″, 12″ …
5×5every 2½″2½″, 5″, 7½″, 10″, 12½″, 15″ …
7×7every 3½″3½″, 7″, 10½″, 14″, 17½″, 21″
  • A 5-patch block at 12″ would need 2.4″ units, which is not a mark on any ruler. Try 10″ or 12½″ instead — Sister's Choice is the 5-patch block on this site.
  • A 7-patch block at 12″ would need 1.714…″ units, which is not a mark on any ruler. Try 10½″ or 14″ instead — Bear's Paw is the 7-patch block on this site.

More about the sizes that do not divide cleanly

The sizes in between

A 10″ Shoofly cannot be cut accurately on its 3×3 grid. Use 9″ or 10½″ instead; both cutting charts are on this page, computed by Quilt Block Atlas.

Both columns are FINISHED block sizes — the size a block will be once it is sewn, never a size to cut. Look the clean size up in the charts on this page for its cutting numbers.

Scroll sideways if the table is wider than your screen.

Whole-inch sizes that cannot be cut accurately for Shoofly, and the nearest sizes that can
Size you wantNearest sizes that cut cleanly
4″3″ or 4½″
5″4½″ or 6″
7″6″ or 7½″
8″7½″ or 9″
10″9″ or 10½″
11″10½″ or 12″
13″12″ or 13½″
14″13½″ or 15″
16″15″ or 16½″
17″16½″ or 18″
19″18″ or 19½″
20″19½″ or 21″

These sizes divide cleanly but sit between the main chart's columns — the same computed cuts, published here so they exist on paper too. Any other clean size still computes in the size input above.

Column headings are the FINISHED block size — the size it will be once it is sewn. Every number in the table is the size to CUT, which includes ¼″ of seam allowance on each edge. Rows that are subcut on a diagonal are cut larger still, so the allowance survives the extra cuts.

Scroll sideways to see every size.

Cutting sizes for Shoofly — between sizes, by finished block size
Patch4½″7½″10½″13½″16½″19½″
Squares — BackgroundCut 42″3″4″5″6″7″
Squares — Fabric ACut 12″3″4″5″6″7″
Squares for half-square triangles — Fabric ACut 2, cut once on the diagonal2⅜″3⅜″4⅜″5⅜″6⅜″7⅜″
Squares for half-square triangles — BackgroundCut 2, cut once on the diagonal2⅜″3⅜″4⅜″5⅜″6⅜″7⅜″

About this block

Pieces in the finished block
13
Unit types
half-square-triangle unit, square
Divides cleanly at
1½″, 3″, 4½″, 6″, 7½″, 9″, 10½″, 12″, 13½″, 15″, 16½″, 18″, 19½″ and 21″ finished.
Also known as
The Eight-Cornered Box, Fence Row, Simplicity
Attribution
Ladies Art Company catalog #276, 1897
Fabric for one 12″ block
¾ yd total, rounded up to the nearest ⅛ yard, assuming 40″ of usable width.

Triangles sit only in the corner positions, which keeps every diagonal at the block's outside corners and leaves the interior crossings straight. Nest those straight seams and everything inside the perimeter falls into place. Square up each corner unit before assembly; its diagonal ends on the block's finished edge, right where the quilt top's joining seam will run.

Piecing order

  1. Make the 4 half-square-triangle units.

  2. Lay out row 1 of 3 and sew its pieces together, left to right.

  3. Lay out row 2 of 3 and sew its pieces together, left to right.

  4. Lay out row 3 of 3 and sew its pieces together, left to right.

  5. Join the 3 rows, matching the seams.

Cutting oversize

The chart gives the standard cut sizes, nothing padded. Some quilters cut this block's triangle units a little oversize and trim back — published allowances genuinely disagree on how much, so the range with its sources is on how to square up a quilt block.

History

The American Farmer published the design in 1896 as The Eight-Cornered Box, and the Ladies Art Company catalogued it as Shoo Fly #276 in 1897 — a catalog number, not a Brackman one. The Kansas City Star ran Eveline Foland's whole-quilt version as Fence Row in 1931. Pattern writers treat it as a chameleon: several later blocks are elaborations of this same nine-cell structure.

Sources: Field Guide to Quilts — Shoofly; Generations Quilt Patterns — Shoofly.


Common questions

What size can I make Shoofly?

Any size it divides cleanly: 1½″, 3″, 4½″, 6″, 7½″, 9″, 10½″, 12″, 13½″, 15″, 16½″, 18″, 19½″ and 21″ finished. The chart above carries 6″, 9″, 12″, 15″, 18″ ready-worked, and the size input computes any other clean size without you doing arithmetic — every value computed by Quilt Block Atlas, none transcribed.

How many pieces are in a Shoofly block?

13 pieces make up the sewn block, but you cut 9. The difference is method: triangle units are cut as squares and subcut, so the chart's quantities are what your rotary cutter produces, not what you count in the diagram.

What sizes does a 3×3 block divide into cleanly?

1½″, 3″, 4½″, 6″, 7½″, 9″, 10½″, 12″, 13½″, 15″, 16½″, 18″, 19½″ and 21″ finished. The step is half the grid this block's cutting sizes are computed on, and the clean-size table above marks this block's row with the other families beside it.

Is Shoofly good for a beginner?

Yes — it scores 2 of 5, easy, on this site's computed scale: 13 pieces, with the half-square-triangle unit as its hardest unit. The scoring rule, and every block ranked by it, is on the difficulty page linked above.

How do finished size, sewn unfinished/trim size, and starting cut size differ?

Finished size is 12″ after the block is sewn into surrounding seams. Its sewn unfinished/trim size is 12½″ before those outer seams, derived with the plain-square allowance. Starting cut size is the method-specific input listed in the chart. Starting cut size equals the unfinished outer target only for a plain square or rectangle workflow; it is not generally the same for pieced triangle units.


Keep going


Measure this square before you cut. It must be exactly 1 inch. If it isn't, your printer scaled the page — reprint at 100% or "Actual size", not "Fit to page".

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