When this applies
- The part has complex or organic surfaces
- You cannot ship the part and it must be captured on site
- You want a digital record of a critical component
- Multiple similar parts need comparing
A scan is not a model
Scanning produces a point cloud or mesh — a description of the surface as it exists today, wear included. Manufacturing needs a solid model with clean features and stated tolerances. The conversion step, sometimes called scan-to-CAD, is engineering work and should be priced as such.
- Scan — captures the surface as-is, wear included
- Mesh clean-up — removes noise and fills gaps
- Scan-to-CAD — rebuilds intended features and dimensions
- Drawing — states materials, tolerances and finish
Where scanning genuinely pays
Complex cast housings, impellers, dies, worn profiles and parts that must mate with an existing irregular surface. For a shaft with a keyway, a caliper and a thread gauge beat a scanner on both cost and accuracy.
Accuracy expectations
Ask what accuracy the scan delivers and whether it is sufficient for the fits on your part. A scan good enough to reproduce a cosmetic housing may not be good enough to define a bearing bore, which is usually measured conventionally and merged with the scanned form.
RFQ checklist
Include these in your request and suppliers can quote without a round of questions.
- Part size, material and surface complexity
- Whether the part can travel or must be scanned in place
- The fits and features that must be accurate
- Whether you want the CAD model delivered
- Quantity of finished parts required