In many manufacturing companies the same problem arises: they have an old part or drawing but want to produce a new version in 3D CAD. Redrawing (reconstruction) of old components allows creation of an accurate 3D model, file preparation for wire EDM or CNC and preserves functionality when modernising.

⚙️ Why is Redrawing Important?

Many parts have no available CAD drawings — especially older machine components from the 1980s and 1990s. Recreating a digital model enables production of new parts, facilitates modifications and optimisation, and minimises production errors through the accuracy of parametric modelling.

🔍 Redrawing Stages

  1. Collecting source data — old technical drawing, photos, physical part, material notes. The more data, the easier it is to recreate the accurate model.
  2. Measurement and 3D scanning — for precision parts, 3D scanning creates a point cloud enabling reconstruction of even complex geometries.
  3. Data analysis — comparison of scan with drawing, dimensional and tolerance verification, identification of critical features.
  4. Creating the 3D CAD model — parametric model in SolidWorks or MegaCAD with closed contours and correct tolerances.
  5. Model verification — checking conformity with the original and applying corrections.
  6. Production preparation — STEP or DXF export, PEPS CAM programming, wire EDM or CNC production.

🧩 Best Practices for Redrawing

  • Collect as much source data as possible — photos from multiple angles, manual measurements or 3D scan
  • Create parametric models that can be easily modified when requirements change
  • Check every critical feature before exporting for production
  • Consult with the wire EDM or CNC machine operator

⚠️ Common Mistakes

  • Inaccurate measurements → dimensional errors in the finished part
  • Ignoring tolerances → assembly problems
  • Unclosed surfaces → PEPS CAM problems
  • No as-built documentation → difficulties in repeat production

💡 Optimisation for Wire EDM and CNC

When redrawing, immediately optimise the geometry for the target production method: simplify contours without losing functionality, avoid sharp corners that extend EDM cutting time and prepare the model so a CAM program can be quickly generated in PEPS.