Why separate labor and elapsed time?

A three-person, one-hour rotation consumes three labor-hours but one clock hour. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.

Does this approve a rigging method?

No. The approved lift plan, ratings, and safety procedure are separate prerequisites. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.

Should initial loading count as a rotation?

No if its time is modeled elsewhere. Count only repositioning events to avoid duplication. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.

Can fixtures reduce rotations?

Potentially, but validate access, blast angle, stability, part protection, and safe load limits. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.

What counts as one rotation?

Count a required transition from one secured blasting orientation to another. Include only changes that need the part or fixture to be repositioned and secured. Ordinary operator movement around a stationary part belongs in the blasting-rate study, not in rotations per part.

Can this be used for crane and rigging plans?

No. It estimates time; it does not approve lifting methods, capacity, rigging hardware, exclusion zones or staffing. Use engineered lift planning and the applicable safety procedure for heavy or complex moves. The calculator can then accept observed positioning and securing times from that approved method.

Abrasive Blasting, Shot Peening & Surface Prep calculator

Blast Part Rotation, Rigging, and Handling Time Calculator

Estimate the handling time required to reposition blast parts using part count, rotations per part, positioning minutes and securing minutes. The calculator totals repeated rotation work, adds documented rigging, verification and allowance baselines, and reports batch labor hours and minutes per part. It is useful when the blast cycle itself is understood but cranes, turntables, fixtures or manual repositioning create a hidden schedule burden. Crew size is fixed at one for a clean baseline. Heavy lifts, tandem handling and engineered rigging plans require a detailed task analysis and must never be reduced to this planning calculation.

What this calculator does

Calculate rotation events, labor content, and elapsed handling time from explicit positioning, securing, verification, rigging setup, allowance, and crew size.
Use it for blast-room schedule, rigging labor estimate, fixture improvement case, quantifying the hidden handling burden of large fabrications with multiple blast orientations..
Calculate rotation events, labor content, and elapsed handling time from explicit positioning, securing, verification, rigging setup, allowance, and crew size.

Formula used

Rotation labor = parts × rotations × positioning and securing minutes, plus fixed rigging, verification and allowance.
Fixed secondary assumptions compiled into this release: Safety and orientation verification: 0.5 min / event; Batch rigging setup: 45 min; Rigging and safety allowance: 20 %; Rotation crew: 2 people.

Inputs explained

Parts: Parts using the modeled rotation method.
Rotations per part: Required repositioning events after initial placement.
Positioning time: Hands-on movement time per rotation.
Secure and release time: Time to make the part stable and then release it.

How to use the result

Best suited to blast-room schedule, rigging labor estimate, fixture improvement case, quantifying the hidden handling burden of large fabrications with multiple blast orientations..
The four-input result is conditional on the disclosed fixed assumptions; use a detailed engineering model when they are not representative. Not a lift plan or rigging calculation. Does not rate cranes, slings, fixtures, floors, or attachment points. Safety procedure controls regardless of output. Crane availability, tandem lifts, engineered rigging, fatigue and safety permits require a separate schedule.

Common questions

Why separate labor and elapsed time? A three-person, one-hour rotation consumes three labor-hours but one clock hour. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.
Does this approve a rigging method? No. The approved lift plan, ratings, and safety procedure are separate prerequisites. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.
Should initial loading count as a rotation? No if its time is modeled elsewhere. Count only repositioning events to avoid duplication. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.
Can fixtures reduce rotations? Potentially, but validate access, blast angle, stability, part protection, and safe load limits. The fixed secondary assumptions are listed on this page and in the downloadable workbook so the four-input result remains auditable.
What counts as one rotation? Count a required transition from one secured blasting orientation to another. Include only changes that need the part or fixture to be repositioned and secured. Ordinary operator movement around a stationary part belongs in the blasting-rate study, not in rotations per part.

Last reviewed 2026-08-24.