Geometry properties
Dimensions are an axis-aligned bounding box in source coordinates. For readable STEP/IGES B-Rep geometry, surface area and valid closed-solid volume use Open CASCADE calculations independently of display mesh resolution. An open surface may have area without enclosed volume. Mesh volume requires closed geometry with consistent outward winding; unavailable volume is not zero.
Units and mass
STEP source units are shown and normalized to millimetres. Mass in grams equals volume in mm³ × density in g/cm³ ÷ 1000. Material presets are generic assumptions; the density is supplied by you, not read from the model.
Assemblies
Totals sum component occurrences, including repeated instances. Overlapping parts are not fused and overlapping material is not subtracted. Hiding a part changes its visibility, not whole-model properties.
Point measurements and comparisons
Circular-edge and cylindrical-wall diameters and edge lengths are calculated from B-Rep geometry. Picked point distances use the tessellated display mesh and are approximate. Simple full cylindrical through holes and flat-bottom blind holes can be classified with depth. Stepped, intersecting and conical-bottom holes remain unclassified. Solid Differences calculates A-only, B-only and common material in original coordinates, shown in red, blue and gray. Each source is fused before comparison, so overlapping assembly material is counted once for this operation. Valid closed solids are required, with at most 100 solids per file. No automatic alignment is performed. Side-by-side and overlay modes remain visual aids.
Verification
Always check a known dimension, geometry validity and expected component count. These tools do not replace drawings, material certificates or engineering acceptance checks. Our editorial policy explains how guide claims are tested on public files.
Native previews and evidence
Native SolidWorks, NX, Inventor, CATIA and X_T previews can arrive as converted triangle meshes. Check the reported representation. Mesh dimensions, area and available volume are approximate; B-Rep edge/diameter measurement and Solid Differences are unavailable for these previews. An extension or a successful preview does not prove an exact solid conversion. Request a self-contained STEP export when the native path fails.
Reproduce the inch-unit check, open-surface check and assembly-instance check. Each includes public self-authored input, observed results and a verification record.
Original article: CADProps · https://www.cadprops.com/accuracy/