A test sheet separates three problems: incorrect size, displacement and incorrect spacing. They need different corrections.
1. Measure one piece
Print the PDF on its intended paper, at 100% / Actual size. Measure the outline width and height. If both shrink similarly, check scale. If only one changes, check document dimensions, distortion and your measurement.
You can use mm or inches: a 100 mm line at 95 mm, or a 4 in line at 3.8 in, both indicate 95% scale. Keep one unit system for each ratio.
2. Check position
A correctly sized piece can be displaced. Lines shifted 2 mm right are not fixed by enlarging every piece.
For pre-cut stock, overlay the plain-paper test and inspect positions. SheetNook centres its grid; commercial sheets can require different margins and a manufacturer template. Also check A4 versus Letter in both document and driver.
3. Inspect distant rows
If the first row fits but later rows drift, inspect pitch: piece height plus gap. An error of 0.5 mm per interval accumulates 3.5 mm after seven intervals. The first row alone cannot verify a whole sheet.
4. Retest after correction
Change one cause at a time and measure again. A convincing on-screen drawing is not enough to move to final stock.
Download your outline template from the planner. Saving it helps reproduce a check, but does not certify a printer, paper or label reference.
References and scope
The numerical examples are our own. Check a physical print on your own equipment.