How much does surface finishing like anodizing or polishing add to the price?
How Much Does Surface Finishing Like Anodizing or Polishing Add to the Price?
There is no defensible fixed percentage for the price added by anodizing or polishing. Calculate the finish adder from two scope-matched quotes: the finished accepted-lot total minus the as-machined accepted-lot total. Keep the drawing revision, material, accepted quantity, inspection, packaging, delivery terms, and schedule equal. Anodizing adds batch preparation, racking, masking, processing, sealing when specified, and post-finish verification. Polishing adds abrasive stages, manual access time, edge protection, cleaning, and surface acceptance. Separate one-time preparation from recurring cost, then divide only the recurring and allocated one-time charges by the accepted quantity.
Calculate the Finish Adder from Scope-Matched Quotes
Finish Type | Quote Lines to Isolate | Acceptance Boundary |
|---|---|---|
Anodizing | Separate minimum or batch charge, preparation, racking, masking, processing, sealing, freight, inspection, and expected rework. | Define alloy and condition, governing specification, type or class, thickness, seal, color, cosmetic zones, masking, and measurement state. |
Polishing | Separate setup, abrasive sequence, hands-on time, protection, cleaning, roughness or appearance inspection, and expected rework. | Define starting condition, polished zones, texture direction, edge rules, visual reference, roughness method, and cleanliness requirement. |
For each finish, report three figures: one-time finish cost, recurring finish cost per accepted part, and the finished unit price. The finish percentage is the unit adder divided by the scope-matched as-machined unit price, multiplied by 100%. This percentage applies only to that quote date, quantity, route, and acceptance scope. If the supplier gives one bundled number, request separate lines for machining allowance, outside processing, transport, masking, finish inspection, and rejected-part replacement. Compare accepted parts rather than starts or pieces sent to the finisher.
Cost Drivers for Anodizing
Anodizing quotes for Aluminum 6061 and Aluminum 7075 are not interchangeable. Alloy, product form, heat-treatment condition, surface preparation, lot appearance, and the released finish specification can alter the route and acceptance risk. Price the following items explicitly:
Color requirement: State the color reference, approved visual sample, viewing conditions, cosmetic zones, and lot-to-lot acceptance rule. A named color alone does not define matching effort.
Type of anodizing: State the governing specification, type or class, target thickness, sealing requirement, functional purpose, and any test evidence. Type language alone is not an acceptance plan.
Masking for selective surfaces: Identify bores, threads, sealing faces, grounding areas, and rack-mark restrictions. Complex boundaries add application, removal, and verification work.
Batch processing volume: State accepted quantity, permitted overrun, lot separation, coupon or sample needs, and replacement responsibility. Minimum charges spread differently as these inputs change.
Anodic coating growth and substrate consumption can affect functional dimensions, but the dimensional effect depends on the specified system and process result. Mark bores, threads, fits, grounding pads, and sealing faces on the drawing. State whether each requirement applies before or after finishing and how it will be verified. Do not let a low finish line item hide extra machining allowance, masking, plug-gauge work, or post-finish sorting.
More details: Anodizing Explained
Cost Drivers for Polishing
Polishing stainless steel, brass, aluminum, or decorative plastic components requires a route matched to the material and starting condition. The labor estimate should expose:
Material hardness: Record the exact grade, condition, stock form, prior process, and starting surface. These inputs affect abrasive choice, heat control, smearing, and edge retention.
Finish grade: Define an approved appearance sample or a complete measurable texture requirement. Terms such as mirror, satin, or smooth are insufficient by themselves.
Part geometry: Mark every polished zone and exclusion. Internal corners, interrupted faces, narrow slots, and protected edges change access and hands-on time.
Post-process cleaning or buffing: Define residue, particulate, compound, lint, handling, and packaging limits that matter to the assembled product.
For a polished SUS304 stainless steel part, a roughness number is quote-ready only when the drawing defines the parameter, cutoff or filter, evaluation length, measurement direction, locations, instrument method, and applicable standard. Appearance also needs controlled lighting, viewing distance, cosmetic zones, and an approved reference when visual matching matters. Without those boundaries, suppliers are not pricing the same finish and their percentage adders cannot be compared.
More details: Polishing CNC Machining Parts
Key Tip: Combine Finishes in Batch
Batch finishing can reduce the allocated setup charge only when parts share compatible material, finish specification, color or texture, masking, racking, inspection, and lot-control requirements. Ask the finisher to confirm which preparation steps are genuinely shared. Do not group dissimilar acceptance states merely to lower the quoted unit adder. Separate functional coating control from cosmetic appearance, and require the quote to show any minimum charge, lot split, sampling cost, and replacement rule.
Manufacturing Services You May Need
Use the linked references for anodizing, polishing, powder coating, and electropolishing to define the RFQ for CNC machining services. Require scope-matched base and finished quotes, then record one-time cost, recurring unit adder, finish percentage, assumptions, exclusions, and quote validity. The resulting amount answers “how much” for the released part; a generic market percentage does not.
