Length & Width Adjustments

Deliberate downscale for an in-between size

In general, every pattern should always be printed at 100% scale, so that you can measure the printing frame and be sure to have a correct outcome. If you have done that already with the first page and you can confirm that your printer setting of 100% results in a correct scale, then you can use the printer scale for a deliberate adjustment in order to achieve your perfect body/ease ratio.

If your body circumference is between 2 sizes, choose the bigger size and use the rule of three for downscaling. For tops compare your chest with the body measurement table of that style. For pants compare your hip circumference with the body measurement table of that style.

Example:
Size M is 39". Size L is 41½". Your chest circumference is 40".
Formula: 100 / (bigger size chest) x (your chest) = % scale
In this example: 100 / 41.5 x 40 = 96.4 %
Printing Size L at 96.4% will result in a perfect width for the desired style. It will have the intended garment ease for your chest circumference. Note that the seam allowances will also be scaled, but with less than 5% deviation, this is negligible. The style will also be a bit shorter which will be addressed further below. 

Scaling the print is the simplest and most balanced solution for an in-between size, as long as the adjustment stays under 5%. Upscaling a pattern is generally not possible because the page would exceed the printable area, unless a projector is used.

 

Manual Width Adjustments

This can be required when the largest size is too small and additional width needs to be added. Any alteration must always be made to the internal seam line, not the external seam allowance, because the seam line lengths must match later.

Step 1)
Draw vertical lines for adding width.
For the side seam and the sleeve inseam draw parallels.


Step 2)

Cut the pattern pieces and spread them apart. Add the same amount at each cut. For the bodice, keep all lines perfectly parallel. For the sleeve, keep the original hem width.

The front armhole and front sleeve must have exactly the same additional seam length. The same applies to the back armhole and back sleeve.

Redraw all affected lines so they remain smooth.

It is important to add the same amount to both the front and back pieces so the shoulder seam lengths match later. This applies to all affected seams. Linings must be adjusted equally to ensure they match the outer fabric.

Manual Length Adjustments

Step 1)
Draw horizontal lines for adding length. 



Step 2)
Cut the pattern pieces and spread them apart. As a rule, add about 75% of the extra length below the armhole and 25% above it.

Bodice and sleeve may require different total length adjustments. However, the armhole and sleeve cap must end up with the same additional seam length, so any difference can only be added in the lower section.

Redraw all affected lines so they remain smooth.

Add the same amount to both the front and back pieces so the side seam lengths match. This applies to all affected seams. Adjust linings equally so they match the outer fabric.