skaletDRAWING BASICS
How to check the scale
of a PDF plan.
Before you measure, separate the drawing’s scale from the size of the paper and the zoom on your screen.
Paper size does not tell you the drawing scale.
A PDF page can have a known size, such as an architectural sheet, and still contain a floor plan, a stair detail, and a wall section at different scales. Check the scale attached to the exact view you intend to measure. Detecting page size alone does not validate those views.
Start with a known printed dimension.
Locate a clearly labeled span whose endpoints you can identify. In Skalet, select the matching preset or saved detail scale and measure that span. If the result does not agree, check your point placement, the selected view, and whether the PDF was resized.
At this scale, one inch on the unchanged PDF represents four feet. A three-inch span represents twelve feet. This relationship comes from the drawing’s dimensions, not from how many inches the screen happens to show.
Zoom is different from resizing a file.
Zooming a PDF on screen changes how large the drawing looks. Skalet stores points in PDF coordinates, so simply zooming does not change a saved dimension. Resizing the drawing within the PDF itself can change the relationship between its coordinates and the printed scale.
Calibrate a resized drawing carefully.
Use two-point calibration when a known span no longer matches the selected scale. Mark the span’s endpoints and enter its actual stated length. Then verify another known dimension elsewhere in that view. If dimensions disagree across the same drawing, the scan may be unevenly stretched or distorted.
Know when to stop.
A single scale factor cannot correct every scan problem. Blurry linework, skewed photos, missing references, and details labeled “not to scale” may prevent reliable measurement. Obtain a clearer source or confirmed dimensions before relying on the result.
Keep scales with the work.
Use named scales for separate details. Saved Skalet measurements retain the scale used when they were created. Choosing a new active scale does not automatically recalculate earlier saved measurements.
Drawing-derived measurements are references. Confirm them against current approved plans and field conditions for decisions about construction or fit.