This is the first in a series of pattern alteration tutorials. These tutorials will cover various ways to enlarge patterns from vintage tissue (your grandmother's Simplicity patterns) to gridded books (Janet Arnold and other notorious sources). This method is best used for patterns that are no more than 5"-6" smaller than your measurements.
If you're into costuming, chances are you've acquired along the way some delightful vintage patterns from the 1930s, 40s, and 50s. Recently I have been very lucky to receive about 11 such patterns...all size 30 bust (or 29 in the example pattern's case). I myself am so NOT a 30 bust, but a size 34. The waist and hip measurements are considerably smaller as well. Luckily, the difference is not too great, which means the shoulders, neck, and probably the skirt lengths/fullness will not have to be changed.
For this tutorial I chose a fairly simple-looking pattern, a lovely 50s summer dress. A look at the back of the envelope shows the pattern pieces - just two pieces for the bodice.
Tools For This Tutorial:
- vellum, heavy tracing paper, or painter's plastic.
- marking pens (I used a variety of colored sharpies)
- a calculator
- a gridded cutting mat (optional)
Step1: Trace the Bodice Front piece, all lines and markings. I use different colors for the stitching line and the cutting line.Be sure to smooth out the piece and line up the edges
Step2: Draw straight horizontal lines across the waist and the bust, so you know where to measure.
Step3: Fold any darts, then take the measurement from the Center Front to the original stitching line. Multiply this number by 4 (front seam left/right; back seam left/right). The resulting number is the total *finished* waist measurement. A second look at the pattern envelope shows a smaller number for our waist measurement. This is because the patternmaker has factored in ease*, about 2" worth. If you prefer to remove the ease now, go for it, or you can wait until a little later on.
(*Ease is the bane of the seamstress' existence! It must be taken out at some point, either before the cutting, or during the fitting. Don't worry, we'll take it out in this tutorial!)
Step4: Now subtract the original pattern's measurement from yours and divide the answer by 4 (in my case, for bust: 34" - 29" = 5"/4 = 1.25") My 1.25" is what I add to *EACH SEAM* at the bustline. Do the same for the waist measurement and hip, if needed. More than likely you will have a different number for the waist as for the bust and hip. Add to your traced pattern by measuring out from the original stitching line. Trace a new Bodice Front piece with the new measurements, if you like.Step5: Trace the original pattern piece for the back. Lucky for you, you've already done the math, so find the bustline and waistline and add on to the side seams the same as for the front.
Step6: Cut out the two pieces, fold up the darts and pin/tape them in place, then pin the pieces on your dressform (or get a friend to pin them on your own body). Paper may seem a bit stiff for this, in which case you're welcome to cut a muslin piece and do it that way, but I find that the paper shows where things are laying incorrectly or fitting funny. Match up the seams on the shoulders. About now you've noticed that side seams are too baggy. This is that ease we mentioned earlier. To reduce this, match the edges, then pinch and pin where the pieces fit the form - this will be your new stitching line. I marked it out in a dotted green line.
Step7: Flatten the pieces out again and straighten the new seamlines with a ruler. Don't forget to add 5/8" seam allowance onto the new stitching line. If the pattern looks too messy, trace out another piece with all the lines and markings.
Congrats! That's really all there is to it. Again, there are several methods for sizing patterns, so use whichever works best for you. Some period patterns, Victorian for instance, will require a different method, or more complicated techniques, but those will be covered in another post.
Lastly, remember to size up any "appendages" to your bodice pieces, such as sleeves. If your armscye measurement has changed by altering the sideseams, you will likely need to add width onto the sleeve cap as well. Waists of skirts will need extensions to fit your new bodice waist, and other styles such as blouses or bodices with collars will need adjustments to the neck measurements and possibly across the shoulders or chest.
More helpful tidbits: If you have used a gridding method to scale period patterns from "Patterns of Fashion," "The Tudor Tailor," or other pattern books, this method will work for enlarging the patterns. However, if the difference is very great (more than 5"altogether), it is suggested that a projector be used to size the entire pattern piece to your set of measurements. The projector method will be covered in a future "How-To" post.