The slit length drives both pieces
Tower and underlap are generated from one opening length so their attachment references stay coordinated.
Sleeve detail
Create a sleeve placket pattern
Generate a tower sleeve placket with a matching underlap strip, fold guides, slit placement, seam allowance, and print-ready exports.
Sleeve placket pieces
Generated example
A sleeve placket built around a measured opening
Tower and underlapThis standard example turns a 12 cm sleeve opening into separate tower and underlap pieces with a 3 cm tower, 1.6 cm underlap, and 3 cm point.
Widths remain editable
Tower width, underlap width, point height, and seam allowance are independent inputs rather than a scaled fixed template.
The live vector includes sewing edges, cutting allowance, fold references, and the tower point used to finish a shirt sleeve opening.
Export the exact placket as tiled A4 PDF, full-size PDF, or SVG.
Related guides
Generator
Basic sleeve pattern
Generate a sleeve block and check cap shape, bicep, wrist, and armhole compatibility.
DetailSleeve cuff pattern
Create a matching cuff with fold line, overlap guide, and button marker.
ConstructionSeam and hem allowances
Read solid seam lines, dashed cutting lines, construction seam allowance, hem allowance, curves, and corners.
Sleeve placket construction guide
Tower and underlap pieces calculated from one sleeve opening
The generator converts an opening length into coordinated tower and underlap pieces with editable widths, point height, folds, and seam allowance.
Tower and underlap
The export includes the visible pointed tower and the narrower layer beneath it, each with its own sewing and cutting references.
The sleeve slit controls the length
Choose an opening that allows the hand through the cuff area while remaining proportional to the sleeve and cuff depth.
Width and point are independent
Tower width controls the finished visible strip while point height controls the peaked finish above the slit.
The lower layer remains narrower
Underlap width is set separately so it covers the opening cleanly without duplicating the tower.
Test folding order and sleeve side
Mirror the detail where needed and test which side receives the tower before cutting the final sleeve pair.
Allowances and folds need full scale
Print at 100%, verify the test square, and transfer every fold and opening mark accurately.
Tower-placket construction
How the tower, underlap and sleeve opening work together
A sleeve placket is a small pattern with strict sequencing. The tower covers the visible side of the cut opening, the underlap finishes the opposite side, and both pieces must extend beyond the opening far enough to secure its top. The generator coordinates their dimensions, but placement and handedness still come from the sleeve.
Choose length from function, not decoration
The opening must be long enough for the cuffed sleeve to pass over the hand and for the sleeve to spread while dressing. A longer opening also needs a longer tower and stable reinforcement at the top. Mark the cut line on the sleeve grain and keep it clear of seam allowances and planned pleats.
Finished width differs from strip width
The visible tower width is only the folded face. The cut piece also contains seam allowance, turn-under and the layer that wraps the opening edge. Follow the generated fold lines in order; trimming the strip to the visible width removes the material required to enclose the raw edge.
Keep the narrow side flat beneath the tower
The underlap should finish the second raw edge without competing with the visible tower. Its folds must stay parallel and its upper end must be caught by the tower reinforcement. If it twists or is attached to the wrong side, the opening will not lie flat when the cuff is closed.
Mirror left and right sleeves deliberately
Traditional shirt plackets place the visible towers in mirrored positions. Mark each sleeve and each placket piece before fusing or folding. A pair cut identically rather than mirrored can put one tower toward the front and the other toward the back.
Placket sample checklist
Practice the entire opening on a scrap with the same grain, interfacing and stitch settings.
- 01 Transfer the cut line, top stop and fold references accurately; reinforce the top before cutting if the fabric shifts or frays.
- 02 Press every fold before attachment and compare the finished tower and underlap widths against the preview labels.
- 03 Cut only to the marked stop, then clip the final corner with control so the sleeve can turn without a hole.
- 04 Topstitch the tower parallel to its edge and secure the upper box or triangle without catching unintended folds beneath.
- 05 Attach a test cuff and confirm hand passage, overlap direction and a flat opening before using the final sleeve.
How and when
Generated from application code
This generator converts the entered measurements into vector geometry. Where a construction has related seams, the software can calculate their lengths; preview, SVG, copyshop PDF, and tiled A4 PDF are produced from the same geometry. These software checks do not replace printing, sewing, or fitting a test sample.
Last recorded review of the generator implementation and documentation: 2026-07-13. The output has not been certified through physical production testing; verify measurements, print scale, seam relationships, fabric behaviour, and fit for your project.
Common questions
Sleeve placket pattern FAQ
Which pieces are generated?
The export contains the tower placket and underlap with folds, sewing lines, cutting allowance, and opening references.
How long should a sleeve opening be?
It must allow the hand through and work with the cuff. Use the sleeve and cuff as context rather than selecting length by appearance alone.
Can I make a narrower tower?
Yes. Tower width, underlap width, point height, opening length, and allowance are editable independently.
Is the same placket used on both sleeves?
The geometry can be mirrored, but the tower direction and garment conventions should be confirmed before cutting paired sleeves.
Which download is best for home printing?
Use the tiled A4 PDF at 100% and measure the 5 × 5 cm square before cutting.
Workflow
01
Choose the placket
Start with standard, narrow, or long placket proportions.
02
Set the opening
Adjust opening length, tower width, underlap width, point height, and seam allowance.
03
Export full size
Download SVG, copyshop PDF, or A4 tiled PDF at print scale.