Quoting Variable Post-Processing Costs

Post-processing is where quotes go wrong. A flat $15 “finishing fee” covers the simple FDM part but loses money on the SLA lattice structure that needs three hours of support removal, or the DMLS component requiring heat treatment, HIP, and CNC machining of critical surfaces.

For digital manufacturers running 3D printing, CNC, or sheet metal operations, post-processing isn’t a line item — it’s a variable workflow dependent on geometry, material, specification, and customer requirements. Quoting it accurately requires the same process logic you apply to the primary manufacturing step.

Why Flat-Rate Post-Processing Fails

Most shops start with flat rates because they’re easy: $X per part for bead blasting, $Y for tumbling, $Z for dyeing. The problem emerges when you compare actuals to estimates:

• Support removal on a 50 cm³ SLA part: 20 minutes vs. 3 hours on a 500 cm³ lattice
• Bead blasting a simple bracket: 5 minutes vs. a complex enclosure with internal channels: 45 minutes
• Thread tapping 2 holes vs. 47 holes across a batch

Flat rates either leave money on the table (underpricing complex work) or make you uncompetitive on simple jobs. Worse, they give customers no visibility into what drives cost — so they can’t optimize designs to reduce it.

Break Post-Processing Into Discrete Operations

Start by cataloging every post-process step your shop performs. For each, identify the cost drivers:

• Support removal: support volume, accessibility, material brittleness, required surface quality
• Surface finishing (blasting, tumbling, polishing): surface area, feature complexity, masking requirements, media type
• Heat treatment: material, volume, cycle time, furnace capacity, fixture needs
• Machining secondary ops: number of operations, setup count, tool changes, inspection points
• Coating/plating: surface area, masking complexity, racking method, thickness spec
• Inspection: CMM time, gauge count, first-article vs. sampling, documentation level

Each driver should map to a measurable input: support volume (cm³), surface area (cm²), hole count, setup hours, furnace cycle hours.

Build Rate Tables From Shop Data, Not Guesses

Track actual labor and consumable costs per operation for 20-30 jobs. You’ll find patterns:

• Support removal scales roughly linearly with support volume for accessible geometries, but jumps non-linearly for internal channels
• Bead blasting time correlates with surface area, but masking adds fixed overhead per masked region
• Thread tapping is nearly linear per hole after the first setup

Convert these into rate tables: base time + variable rate per unit of cost driver. Example for support removal:

• Base handling: 5 minutes
• Accessible supports: 0.8 min/cm³
• Internal/constrained supports: 2.5 min/cm³
• Delicate material multiplier (e.g., ceramic-filled resin): 1.5x

This approach works because it’s grounded in your equipment, people, and materials — not industry averages.

Automate Driver Extraction From Geometry

Manual measurement doesn’t scale. Your quoting engine should extract cost drivers directly from the customer’s CAD file:

• Support volume from slicer preview (for additive)
• Surface area from mesh analysis
• Hole count, thread specs, counterbore depth from feature recognition
• Critical surface callouts from PMI/annotations or drawing parsing

When a customer uploads a revised model, the drivers recalculate automatically — no re-keying, no estimator bottlenecks. This is where integrated quoting software pays off: the geometry analysis happens once and feeds both the primary process quote and every post-process step.

Handle Customer-Driven Variability

Customers introduce variability through specifications:

• “Remove all visible layer lines” vs. “functional finish only”
• “Heat treat per AMS2759” vs. “stress relieve only”
• “Certificate of conformance” vs. “full FAIR with CMM report”

Build specification tiers into your quote engine. Each tier maps to a defined set of operations, inspection levels, and documentation requirements. The customer selects (or you recommend) a tier, and the post-processing quote builds itself from the associated rate tables.

Quote Post-Processing as a Configurable Workflow

The end goal: post-processing quotes that adapt like manufacturing quotes. When any input changes — geometry, material, quantity, spec tier — the post-processing cost recalculates instantly. No spreadsheet gymnastics, no “let me check with the shop” delays.

Solvi’s quoting engine handles this by treating post-processing as a first-class workflow: configurable operations, geometry-driven cost drivers, spec-tier logic, and automatic recalculation on revision. Shops using this approach report quoting complex post-process chains in minutes instead of hours, with margins protected by actual shop data.

See how Solvi builds variable post-processing into instant quotes.