Printing Without Losing Scale

What you take from this lesson: Print any pattern at exactly the right scale and know how to check it before you put the scissors to the fabric.

The error you can't see

It is the most expensive mistake in all of digital patternmaking, and it is so precisely because you don't notice it. The printed pattern looks perfect: every line, every piece and every mark is there. The only thing that happened is that it measures 4% less than it should.

You cut the fabric with that pattern, you sew the garment, and only then does the problem show up: the garment doesn't close, or it fits one size smaller than the label says. By then the production run has already been cut.

Where it comes from

From an option that almost every PDF reader has turned on by default: "fit to page," "scale to printable area" or "shrink to fit."

Printers can't print all the way to the edge of the paper: they leave a margin they can't reach. When the reader detects that the drawing fills the whole sheet, it shrinks it slightly so it fits entirely within the printable area. This behavior is designed for text documents, where it doesn't matter. On a sewing pattern, it ruins everything.

How to print it correctly

Three decisions before you hit print:

• Scale: 100%, "actual size" or "custom scale: 100." Never "fit."
• Paper size: the same one the file was set up for (A4). If your printer only takes Letter, print at 100% anyway and accept that some margin gets cut off: the scale stays the same, and that is what matters.
• Orientation: whatever the file uses, with no automatic rotation.

The ruler check

Every pattern includes a test square on the first sheet, with its measurement written next to it. Print only that sheet, measure it with a ruler and compare.

If it measures what it says, you're good and can print the rest with confidence. If it measures less, there is no point in compensating by cutting larger: you need to fix the settings and print again.

It is half a minute of work that protects your entire production run. No other check in the whole process has that ratio of effort to risk avoided.

When the printer is the problem

There is a less common case: the square measures correctly in width but not in height. That is not a settings problem; it is the printer feeding the paper unevenly, which is typical of older home printers.

There is no software fix for it. Your options are to print somewhere else or switch to the plotter format, which comes out on a continuous sheet and doesn't depend on sheet-by-sheet feeding.

Common mistakes

• Printing the whole pattern without first checking the test square on a single sheet.
• Leaving the fit-to-page option turned on.
• Compensating for a badly printed pattern by cutting "a little bigger."

In short

Print at 100%, without fit to page, and check the test square with a ruler before printing the rest. Half a minute that protects your entire production run.