Welding & Fabrication worked example

Grinding and Finishing Time at 18% disc change, inspection, and break allowance: a worked example

This worked example runs the grinding and finishing time numbers for a tougher week than the baseline: 18% disc change, inspection, and break allowance instead of the typical 25%. Estimate weld grinding and finishing time from inches of weld to finish, finish inches per minute, and a setup and changeover allowance.

The inputs for this scenario

  • Inches of weld to grind and finish: 120 in (held at the documented default)
  • Finish inches per minute: 12 in / min (held at the documented default)
  • Disc change, inspection, and break allowance: 18 % (the input this scenario stresses; the baseline uses 25)

Working through the calculation

  • The calculation starts from the formula this tool documents: Base grinding and finishing time = inches of weld to grind and finish รท finish inches per minute.
  • Required grinding and finishing time works out to 11.8 min at these inputs, and this is the headline figure for the scenario.
  • Base grinding and finishing time works out to 10 min at these inputs.
  • Disc change, inspection, and break allowance works out to 18 % at these inputs.
  • Finish inches per minute works out to 12 pieces / min at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where disc change, inspection, and break allowance sits at 25% and the headline result is 12.5 min, this scenario comes in 5.6% below the baseline at 11.8 min.
  • Use it when quoting cosmetic or blended welds, sizing finishing-bay labor, or checking why a job's post-weld hours keep blowing the estimate. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Required grinding and finishing time: 11.8 min (headline result)
  • Base grinding and finishing time: 10 min
  • Disc change, inspection, and break allowance: 18 %
  • Finish inches per minute: 12 pieces / min

Run it with your numbers

  • To rerun this with your own numbers, open the live Grinding and Finishing Time calculator, set disc change, inspection, and break allowance to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.