When Customers Send STEP Files With Errors

Every shop gets them: STEP files with missing faces, open edges, flipped normals, or units that don’t match the drawing. The customer expects a quote by lunch. Your CAM seat is tied up trying to heal geometry that should have been clean.

Bad CAD doesn’t just waste programming time — it creates quoting risk. If you guess at the repair effort, you either underquote and lose margin or overquote and lose the job. The fix isn’t better CAD software; it’s a repeatable triage process that lets you quote accurately and move to production fast.

Classify the File in Two Minutes

Open the STEP in a lightweight viewer — not your full CAM seat. Check four things:

• Watertight? Rotate, section, and run a quick edge/face count. Open edges = repair time.
• Units match the drawing? A 10 mm part modeled in inches is a 254 mm surprise.
• Single body or assembly? Nested components, duplicate bodies, and hidden construction geometry inflate bounding-box estimates.
• Feature recognition viable? If your CAM can’t see holes, pockets, or threads, you’re programming from scratch.

Tag the file: Clean, Minor Repair (under 15 min), Major Repair (15–60 min), or Remodel Required. This classification drives the quote line item, not a gut feel.

Build a Repair-Time Library

Track actual repair minutes by failure mode for 20–30 jobs. You’ll end up with a small lookup table like:

• Heal open edges < 0.1 mm: 5 min
• Re-create missing fillets/chamfers: 10 min per feature
• Revolve/loft from 2D profiles: 20–40 min
• Full remodel from 2D print: 2–4 hrs

Next time a file lands in Minor Repair, you add the library time to the quote. No guessing, no padding “just in case.”

Automate the Easy Wins

Script the repetitive checks. A Python + OCC or CadQuery routine can:

• Read units from the STEP header and flag mismatches
• Count open edges and report total gap length
• Extract bounding box vs. drawing envelope
• Output a one-page PDF “File Health Report” for the estimator

Run it as a pre-quote gate. The estimator sees the report, picks the right library line, and the quote goes out in minutes — not hours.

Communicate With the Customer Without Sounding Difficult

Send the File Health Report with two options:

1. We fix it. Here’s the added cost and lead-time impact (from your library).
2. You fix it. Here’s exactly what’s wrong (screenshots + edge list). Re-upload when ready.

Most customers choose option 1 because they see a precise number, not a vague “engineering fee.” You convert the RFQ faster and start with clean data.

Feed Clean Geometry Back Into the Quote Engine

If your quoting engine ingests STEP files for automatic volume, surface-area, or nesting calculations, the repaired model must replace the original — silently. Version the file: PN1234_v1_customer.step → PN1234_v2_quote-ready.step. The quote engine always references the latest quote-ready revision so material and time calcs stay accurate.

Close the Loop on the Shop Floor

The same File Health Report travels with the job packet. Setup and programming see the known issues up front — no “why doesn’t this fillet exist?” discoveries at the machine. If the repair library said 10 minutes and it took 25, update the library. Continuous improvement, not tribal knowledge.

Bad CAD files aren’t going away. Shops that treat them as a measurable, billable step — instead of a fire drill — quote faster, protect margin, and hit lead times. Solvi helps you embed that triage into the quoting workflow so every RFQ moves from file to firm price in minutes.