Rack vs Barrel Plating Cost Per Part Calculator
Choosing rack or barrel is a cost question driven by part size, volume and quality needs. This calculator compares the two on a per-part basis using labor, line time, rack upkeep, metal and rejects, and shows how barrel load size changes the answer.
Your numbers
Zinc 7.14, nickel 8.9, copper 8.96, tin 7.31.
Share of purchased metal that ends up as deposit after dragout and sludge losses.
Depreciation, chemicals, utilities, wastewater and floor space per line hour.
Time the line is occupied per rack position, set by the hoist cycle.
Barrel plating gives wider thickness spread, so more average metal is deposited to meet the minimum.
Your results
Model uses direct labor, line time and metal. It excludes quality inspection, setup, masking, packaging, waste treatment surcharges and tax, which should be loaded through your overhead rate.
Cost per part vs parts per barrel load
Sweeps Parts per barrel load from 200 to 5000, holding your other inputs fixed.
Finishing cost model review
Want plating costs calculated from live routing and rate data? We can discuss how to set up a private cost assistant.
Optional. The tool and every export work without this. No spam.
How to use it
Enter lot size, area, thickness and metal price. Then fill in the rack side (parts per rack, handling time, line index time, strip cost, rejects) and the barrel side (parts per load, handling, cycle time, simultaneous barrels, uniformity penalty, rejects). Compare the two per-part costs. The chart sweeps barrel load size, which shows the point at which barrel overtakes rack. Small, bulk, robust parts typically favor barrel; larger or cosmetic parts, and anything that tangles or dents, favor rack.
- Use your loaded labor rate, not the hourly wage
- Set line overhead from annual line cost divided by productive hours
- Reflect reject rates from real data, not goals
- Run the sweep to see sensitivity to load size
How the cost model works
Metal cost per part is deposited mass priced by weight and divided by utilization. Rack cost adds handling labor per rack, line occupancy at the hoist index time, and rack strip or repair per use. Barrel cost adds handling per load and line time of cycle time divided by the number of barrels processed together. Barrels get a metal penalty because thickness spreads more widely, so more average deposit is needed to meet a minimum. Total cost is divided by the good-yield fraction to include rework or scrap.
Reading the result
At small areas and large volumes the barrel is far cheaper because handling and line time are shared across thousands of parts. As parts get bigger the barrel load shrinks and the advantage collapses. Cosmetic requirements, thickness tolerance and part damage in tumbling can force rack work even when it costs more. If the two are within a few cents per part, quality risk should decide, not the calculator.
Common mistakes
Shops often compare cycle times but not line occupancy, ignore rack strip and repair cost, and forget that barrel work needs extra metal for uniformity. Another mistake is using a single overhead rate for different lines. If barrel and rack lines have different costs per hour, run the model with each line's rate.
Frequently Asked Questions
When is barrel plating cheaper than rack?
Barrel is usually cheaper for small, durable parts in large quantities, because handling and line time are spread across thousands of pieces. It struggles with parts that nest, tangle, scratch, or need tight thickness distribution.
What does plating cost per part include?
Direct labor for racking and unracking, line time (chemicals, utilities, depreciation), metal, rack or barrel wear, and scrap or rework. This model leaves out inspection, packaging, masking and treatment surcharges, which you can load through overhead.
How do I set the line overhead rate?
Divide the annual cost of the line, including depreciation, chemicals, power, wastewater, maintenance and space, by its productive hours. Separate rates for rack and barrel lines give a better comparison.
Why does barrel plating use more metal?
Barrel parts see widely varying current density as they tumble, so thickness spreads more widely than on a rack. To ensure every part meets the minimum, the average deposit must be thicker, which consumes more metal.
If your job costs are in an ERP, we can help build an assistant that applies routing times, rates and yield data to quote plating work consistently, hosted on your own infrastructure.
Related Tools
Electroplating Thickness and Time Calculator (Faraday)
Compute plating time, deposition rate, total amps, amp-hours and deposited metal weight from current density, cathode efficiency and target thickness.
Engineering & PLMPlating Part Surface Area Estimator
Estimate plated surface area for a prismatic part with through holes and bosses, then convert to dm2, ft2 and load amps for the whole lot.
Costing & FinancePlating Job Quote and Pricing Worksheet
Quote multiple plating or anodize line items with computed metal cost, labor, setup, margin and unit price, then export to Excel.
Quality & InspectionPlating Bath Analysis and Additions Log
Log bath analysis results with targets and control limits, compute deviation and out-of-range flags, and record additions for audit and Nadcap-style records.
More Costing & Finance tools
See all- SAP QM Inspection Effort and Cost Calculator
- SAP Standard Cost Estimate BOM Rollup Calculator
- Legacy ERP Retirement Cost and Payback Calculator
- JD Edwards World Month-End Close Procedure Template
- Distributor Customer Credit Application Template
- Distributor Customer Profitability Worksheet
- Distributor GMROI and Inventory Turns Calculator
- Vendor Early Pay Discount Worksheet
- SyteLine Cost Rollup Variance Calculator
Keep exploring
Free tools
- Plating Job Quote and Pricing WorksheetQuote multiple plating or anodize line items with computed metal cost, labor, setup, margin and unit price, then export to Excel.
- Plating Line Process Card and Traveler TemplateFill in a plating traveler with part, specification, process steps, thickness and adhesion checks, bake record and sign-offs, then export.
- Barrel Residence Time CalculatorEstimate how long resin sits in the barrel and how much of the machine capacity a shot uses, to spot degradation risk from oversized presses.
Guides
- Plating Pricing Methods: Surface Area, Rack, Barrel or Per Piece?How metal finishing shops price plating and anodizing by surface area, rack, barrel load or piece, with a worked example and the margin traps in each method.
- Plating Job Shop Quoting Software: What a Finishing Shop Actually NeedsPlating and metal finishing job shop quoting: how to price from spec, area, rack count and minimum lots, and where AI can draft quotes from customer POs.
- ERP for Metal Finishing and Plating Job Shops: What to RequireHow to choose ERP for a plating, anodizing or heat treat job shop: process routing, rack tracking, spec library, certs, and when job shop ERP beats a niche package.