Module 3

Drafting the Basic Block

In Module 3 you will apply the foundational concepts you learned in Modules 1 and 2 to the first full drafting sequence of the course. Here, you will translate your body measurements into a five-piece dress block (or “basic pattern set”) that can be tested, reused, and modified. Patternmaking for Fashion Design provides all the instructions needed to draft a basic pattern set; however, feel free to use the other readings provided below as a supplemental resource, or to clarify concepts with external resources as needed.

Note: if you find that Armstrong’s drafting method isn’t working for you, Metric Pattern Cutting for Women’s Wear by Winifred Aldrich also provides detailed instructions for drafting bodice, skirt, and sleeve blocks from body measurements. Aldrich’s methods use slightly fewer measurements, and result in a front and bock bodice that are drafted as a unit pattern piece, with waist shaping added in later. Aldrich’s front bodice also differs from Armstrong’s in that the dart is split into both a waist dart and a shoulder dart. Choose the method you find works best—it doesn’t matter which, as long as it produces a basic pattern set that works for you.

Readings

Patternmaking for Fashion Design Pages 43-73: Drafting and fitting the basic pattern set

Optional: Metric Pattern Cutting for Women’s Wear Pages 24-26: Basic skirt block Pages 61-63, 77, 80: Basic fitted bodice Pages 70-71, 126: Basic sleeve block Pages 216-226: Assessing fit, pattern alterations

Optional: The Pattern Making Primer Pages 50-52: Basic slopers Pages 78-93: Fitting, pattern adjustments

Optional: Reader's Digest Complete Guide to Sewing Pages 36-53: Pattern adjustments

Optional: The Sewing Book Pages 62-75: Pattern adjustments

For this module, you’ll draft the fitted bodice, straight skirt, and set-in sleeve blocks directly from the measurements you recorded in Module 1. Once they’re finalized, these blocks will provide a technical reference from which you will develop new garments in the following modules. Accurate drafting is crucial at this stage, as small inconsistencies can cascade through iterations, cumulatively affecting the fit and construction of your designs. Consequently, as you draft your blocks, make sure that the dart intake, dart placement, and leg alignment are measured and trued so the darts shape the garment properly. True and walk all your seams as well, so adjoining pattern pieces meet smoothly at the waist, neckline, and armhole, and can be sewn together without needing adjustments. Meticulous drafting will ensure that fit issues in the corresponding muslin aren’t obfuscated by technical errors.

Studio Note

Truing Seams

When a draft looks “almost right,” resist the urge to ignore small mismatches. A slightly uneven dart leg, an untrued seam, or a sleeve cap ease that is a little too generous can become much more obvious once you start manipulating the pattern in later drafts and sewing it into a garment. Before finalizing a pattern:

Match adjoining seams at the stitching line and check that their lengths agree between corresponding points.
Walk curved seams together or use a curved/flexible ruler to ensure that measurements match.
Fold darts closed along the centerline, match the dart legs, and redraw the adjoining edge while the dart is folded.
Check curves along closed darts and joined seams. If an armhole, neckline, waistline, or other edge forms a point, dip, or lump at the join, use a curved ruler to blend the line.
Recheck seam lengths after making corrections—even a small change to a curve can change the length of a seam.

As part of the drafting process, you will iteratively test and evaluate each component of your block using a muslin. Sewing and trying on your muslin will provide the first opportunity to ensure your block fits, determine how it corresponds to the shape of your body when it’s fully assembled, and see how all five pattern pieces work together as a whole. Work piece-by-piece: start with the front and back bodice, then once the bodice fits, move on to adding the skirt and the sleeves. This will allow you to adjust the block before it's used as the basis for future designs. Note that the first block rarely fits perfectly on the first attempt. Early corrections are part of the drafting process!

Studio Note

Tips for Sewing a Muslin

Your muslin is a working draft of the basic pattern set and should be treated as such—it should be well labeled and easy to evaluate, alter, disassemble, and compare with other versions. A few simple habits during construction can make the muslin fitting process more useful:

Use contrasting thread so you can easily see seamlines and stitching.
Sew with a longer stitch (~3 – 3.5 mm) so you can unpick and adjust seams as needed.
Leave your seam allowances unfinished.
Mark important reference points on the outside of the muslin. At the very least you should include the bust apex, horizontal balance line at waist (or waist seam), horizontal balance line at hip, center front, and center back.
Mark notches and drill marks the way you would when sewing a normal garment.
Press the muslin well (high heat, no steam) before you try it on so wrinkles don’t interfere with your ability to evaluate fit.
For earlier versions, pinning the garment closed is perfectly acceptable. As you get closer to the end of your fitting journey, consider using a zipper (any cheap, 20” – 25” dress zipper should work fine).
Note any areas where darts and seams need to be trued, or where pattern pieces don’t properly align.
Label each muslin with the draft number and date so you can connect fitting notes and pattern corrections to the right version.
Write fitting changes directly on the muslin when useful, including pinned amounts, seam adjustments, and areas that need more or less width or length.

Any adjustments you make during the fitting process should be transferred back to the block pattern in a new draft. Keep a record of any changes. The final, corrected block will be used as a starting point for later pattern development, so revisions should be well documented and easy to follow. Keep your pattern pieces clearly labeled and organized according to the system you developed in Module 1 in case you need to reference earlier drafts or previous corrections.

Fit and Style Reflection

Assessing Fit

After sewing your first full muslin, notice how it sits on and interacts with your body. A block should follow the contours of your body closely, making the pattern easier to evaluate. Your personal preferences for ease and silhouette may also become clearer at this stage. Record these observations and be sure to modify your block as needed.

How does the fitted bodice feel across your bust, upper back, and waist when you breathe deeply or bend your torso?
How does the straight skirt silhouette and dart configuration align with the shape of your hips?
How does the sleeve feel when you reach forward or raise your arms?
Does the bust apex sit at the fullest part of your bust?
Does the waistline sit horizontally across the front, sides, and back of your natural waist?
Which parts of the muslin feel secure and balanced on your body? Are there any areas that highlight asymmetries or imbalances?
Do you notice any areas of tightness, restriction, or gaping that need to be adjusted?

Studio Note

How Much Ease in a Dress Block?

As you work through muslin fittings of your basic pattern set, you may start to wonder “how much am I supposed to be able to move in this thing?!” A basic dress block is meant to be evaluated as a static, fitted garment. It should include enough comfortable wearing ease to allow for normal breathing and some mobility, while sitting close enough to your body to serve as a reliable foundation for later pattern development. A good rule of thumb is 2” – 3” ease in the bust, 1” – 2” in the waist, 2” – 3” in the hip, and 2” – 2.5” in the bicep, but feel free to adjust these amounts based on the ease preferences you recorded in Module 1.

Some helpful reference points for movement in a set-in sleeve dress block are:

Arms raised forward: you should comfortably be able to reach 90° (about shoulder height) without the underarm seam yanking or the side seam of the bodice hiking up more than an inch or so. 120° is optimal.
Arms raised to the side: you should be able to comfortably raise your arms to shoulder level at 90°. Due to the shape of the sleeve, most blocks won’t allow you to reach overhead without the bodice and waist pulling up.
Arms crossed in front of chest: full, comfortable crossing usually isn’t expected from a basic block in unforgiving woven fabric like muslin—some tightness across the back and underarm is typical. You should be able to get your arms most of the way across without the garment feeling like it’s about to rip.

After all your pattern corrections are completed and you are happy with the fit of your muslin, the final draft of your bodice, sleeve, and skirt blocks should be documented in three formats:

Paper seamed versions should include seam allowances and all markings and technical information, and will serve as references for construction and garment assembly
Tagboard net versions without seam allowances will allow pattern pieces to be traced repeatedly
Half-scale net tagboard versions will support paper-based exercises to allow for efficient experimentation
If you have access to Adobe Illustrator or similar software, you may also choose to document the seamed and net versions of your blocks in a digital format for later use

Storing your blocks and patterns in these formats is part of a flexible working system that will allow your patterns to be reused and adapted throughout the manual. It will also make it easier for you to revise your blocks as needed should you find yourself making the same adjustments over and over again as you adapt them into new designs.

Studio Note

Adjusting the Ease of the Block

As you fit your muslin, you may have noticed that the amount and distribution of ease that felt “right” changed as you added components to the dress block. For example, the bodice may have fit well without sleeves, but became restrictive once the sleeve was added. Likewise, a skirt block that may have fit on its own may have needed slightly more ease at the waist when joined to the bodice. It is perfectly acceptable to draft different versions of a block for different purposes, such as a separate skirt and dress block or separate sleeved and sleeveless bodice blocks, as long as each version is labeled clearly.

If you need to adjust the amount of ease in your block, you can change the amount or distribution of dart intake using the methods you learned in Module 2 and then re-true the affected seam. For instance, you can release some dart intake into the waistline to add circumference (just be sure to release the same amount in the bodice and skirt, and check that these seams are properly trued). For a sleeved bodice, you can also redistribute ease toward the armscye or add it through the side seam or shoulder seam as needed.

More information can be found in Patternmaking for Fashion Design on Page 67 and Metric Pattern Cutting for Women’s Wear on Page 76.

Learning Outcomes

By the end of Module 3, you should be able to:

Draft a bodice, straight skirt, and set-in sleeve block accurately from your body measurements
True darts and seams so that adjoining edges match in length and shape
Construct and evaluate a muslin to assess fit and balance
Identify visible fit issues and describe them using the correct terminology
Know which pattern adjustments to use for specific fit issues
Diagnose proportional and alignment issues in a block and transfer corrections back to the paper pattern

Module 3 is complete when your basic pattern set fits correctly, is well-balanced, and can serve as a reliable foundation for experimentation and pattern manipulation in subsequent modules.

Module 3 Block Checklist

Draft bodice, skirt, and set-in sleeve blocks from body measurements
Draft paper seamed versions of bodice, skirt, and sleeve blocks with 5/8” seam allowances clearly delineated. Sleeve with elbow dart should match sleeved bodice armhole
Draft tagboard net/unseamed versions of bodice, skirt, and sleeve blocks
Draft paper and tagboard net half-scale versions of bodice, skirt, and sleeve blocks for paper-based exercises
Optional: Draft digital versions of bodice, skirt, and sleeve blocks using Adobe Illustrator or similar software
True all darts and joining seams
Sew and evaluate sleeveless bodice muslin, sleeved bodice muslin, and skirt muslin
Apply necessary fit corrections to blocks
Label, archive, and document final block versions using the system you developed in Module 1