Barrel Plating Services
When you need thousands of parts plated fast, capacity matters. With 30-barrel zinc plating stations running daily, we move high-volumes quickly while maintaining consistent coverage. You get the throughput you need and the reliable quality your customers expect.
Why Choose Gatto for Barrel Zinc Plating
Our barrel plating lines are built for dependable results. We continually refine our approach to keep quality steady, turnaround predictable, and make sure your parts have a finish that won’t cause issues during your next stages of production.
- Capacity – With 30+ barrel plating stations running daily, we process thousands of parts at once while maintaining consistent coverage.
- Zinc & Zinc-Nickel Finishes – Zinc delivers cost-effective corrosion protection for a wide range of industrial parts, while zinc-nickel provides a higher level of durability for harsher environments.
- Uniform Coverage – Our alkaline process improves coverage in low-current-density areas like corners, recesses, and holes which reduces low coverage areas and boosts long-term protection.
- Ideal for Small, Durable Components – Fittings, bushings and small stampings are well-suited for our bulk process, providing a high performing finish without the cost of individual handling.
- Cost-Efficient Processing – Our barrel plating lines process small parts in bulk, allowing high volumes to move quickly with a lower cost per piece.
- Rack + Barrel Flexibility – If barrel plating isn’t the right fit, our 15-station rack lines run larger or more delicate components, so you have both options under one roof.
- Proven Quality Control – Daily bath testing, ISO 9001:2015 certification, in-process quality checks, and 50+ years of zinc and zinc-nickel expertise ensure your parts get the consistent coverage they need to perform in the field.
How Our Process Improves Coverage and Durability
More Uniform Coverage on Hard-to-Reach Areas
Our alkaline barrel process improves coverage in corners, recesses, and other low-current areas that naturally plate thinner. We use chemistry with stronger throwing power to help the finish reach difficult features and reduce edge buildup. These areas will still plate thinner, but the process delivers better overall coverage compared to alternative barrel processes.
At Gatto, we actively monitor parts throughout plating so we can adjust part orientation, barrel speed, and bath chemistry to achieve optimal coverage.
Better Ductility for Bending and Forming
When plated parts are bent or formed later in production, a brittle coating can crack as the metal moves. Our alkaline process produces a more ductile finish that flexes with the part, protecting against cracking or peeling and helping it maintain quality requirements through forming and assembly.
What is Barrel Zinc Plating
Barrel zinc electroplating is designed for small, durable parts that can be finished in bulk rather than hung individually on racks.
Components are placed in a perforated, non-conductive barrel that rotates slowly while immersed in plating solution. Electrical contact is maintained through danglers or conductor bars inside the barrel, allowing current to reach the parts as they tumble.
This tumbling motion also helps improve coverage in areas that might otherwise be “shielded,” such as corners, recesses, or surfaces blocked by neighboring parts. At the same time, the action smooths small burrs and ensures consistent exposure to the solution.
Once plated, parts are treated with a chromate conversion coating for added corrosion resistance, then rinsed and dried.
The result is an industrial finish applied quickly and cost-effectively to thousands of parts at once.
Advantages of Barrel Plating
While some parts require different processing methods, barrel plating delivers distinct advantages when applied to the appropriate hardware.
- Cost-Effective For Volume – Bulk handling lowers labor and reduces cost per piece compared to rack plating.
- Efficient Throughput – Thousands of parts can be processed in a single run, keeping production schedules on track.
- Improved Coverage – Tumbling helps distribute metal more evenly, especially in corners and recesses that are otherwise hard to reach.
- No Rack Marks – Since parts aren’t hung individually, there’s no risk of contact marks from rack fixtures.
- Light Deburring – The barrel motion naturally smooths small burrs or sharp edges.
Barrel plating works best for small machined components, hardware bushings, fittings, valves, and stampings that can tumble together without damage. For parts that require individual handling rack plating is often the better option.
Barrel vs. Rack Plating – What’s the Difference?
While barrel plating processes thousands of small parts in bulk, rack plating means parts are individually handled, hung and secured to a rack, keeping them separate throughout plating. This extra handling prevents parts from touching or damaging each other and makes it possible to plate larger, delicate, or complex components with care.
Here’s a general guide for determining when barrel or rack plating is the better fit for your parts:
Barrel Plating Is Best When:
- Parts are under ~7" in length and weigh less than 1 lb
- You need to process thousands of small parts
- Parts can withstand hours of tumbling without bending, breaking, or nesting
- Bulk handling is acceptable for cost efficiency
- Minor surface marks are acceptable, and full cosmetic perfection isn’t required
Rack Plating Is Best When:
- Parts are larger- typically over ~7–8" or heavier than ¾ lb
- Thin, fragile, or tight-tolerance parts need individual handling
- Flat or nestable shapes (clips, sheets, plates) risk stacking or shadowing
- Critical surfaces or cosmetic finishes can’t risk marks from tumbling
- Complex geometries require precise positioning for uniform coverage
When Barrel Plating Isn’t the Right Fit
Barrel plating relies on hours of tumbling, where thousands of parts move freely against each other as the finish is applied. That constant motion makes the process efficient for high volumes, but not every component can withstand the contact.
Parts that bend, tangle, or trap solution often come out with rejects or damage, making rack plating or another method the better choice.
Common examples of parts that don’t run well in a barrel include:
- Threaded Parts –Tumbling can nick, roll, or damage thread edges, making them difficult to assemble, especially on finer threads or heavier parts.
- Thin Or Fragile Components – Fine walls, delicate threads, or tight-tolerance features can deform or distort under constant tumbling.
- Flat Or Nestable Shapes – Clips, plates, and washers may stack together, blocking solution flow and leaving bare spots that require rework.
- Tangling Geometries – Springs, hooks, or U-shaped pieces can interlock, blocking current from reaching all surfaces and creating a “ball” of parts that must be separated.
- Large Or Heavy Parts – Hardware heavier than ~1 lb or longer than 6–7" doesn’t rotate effectively, often leading to uneven coverage.
Note on Small Quantities: For barrel plating to coat parts evenly, there must be enough volume in the barrel for parts to tumble properly. Small batches may not create enough movement and can produce an uneven finish. In those cases, rack plating is usually a more consistent and cost-effective solution.
Understanding Fallout in Barrel Plating
Barrel plating fallout refers to parts that come out of the barrel with defects such as incomplete coverage, over-plating, nicks or dents, staining, or discoloration. These issues often occur when parts nest, stack, or catch edges during tumbling, which can shield surfaces, interrupt electrical contact, or create scratches.
On average, a fallout rate within 1% is typical in barrel plating. This tradeoff is part of what makes the process economical and efficient. Thousands of parts can be finished quickly at scale, with the understanding that a small percentage may require rework or rejection.
Good practices can minimize fallout, but because it’s inherent in bulk processing, it can’t be eliminated entirely. If your parts require cosmetic perfection, highly consistent coverage, or zero tolerance for defects, rack plating is the better option. Individual handling provides more control and reduces fallout risk, though at a higher cost per piece.
Barrel Zinc Plating Across Industries
Every industry relies on small but critical parts, and when they fail, entire systems are at risk. Our barrel zinc plating services keep your projects moving by finishing hardware to the specifications your industry demands.
- Electronics & EV power – Connectors, clips, contacts and terminals plated with zinc or zinc-nickel, meeting ASTM B633 and AMS 2417 requirements.
- Construction & Building Hardware – Clamps, brackets, hinges, and anchors finished for long-term durability in harsh environments, plated to ASTM standards.
- Heavy equipment & Agriculture – Couplings, fittings, and washers processed to specifications such as Caterpillar 1E09737F and John Deere JDM F21.
- Transportation & Aerospace – Fittings, bushings and hardware plated to OEM requirements for rail, bus, aerospace applications and other high-reliability applications.
- Automotive – Stampings, brackets, and bearings efficiently processed to OEM standards like Ford WSS-M1P85, Toyota TSH6500G, Tesla TM-0009F-M and GMW 4700.
For more details on specific industries and specifications, see our Industries page.
Barrel Zinc Plating: Frequently Asked Questions
Durable hardware like fasteners and washers run well. Thin or fragile parts may be better suited for rack plating.
Parts under ~1 lb and 7" long may be good candidates for barrel plating.
Alkaline chemistry improves coverage in hard-to-reach areas, producing a more consistent finish.
No. For parts that are suitable for the process, barrel plating is typically a low-cost option to bulk process parts quickly.
Fallout in barrel plating is typically within 1%. Because parts tumble and make frequent contact during bulk processing, a small amount of fallout is normal. Components with delicate features, tight tolerances, or geometries not well-suited for tumbling may see higher fallout rates.
Send us your drawings or samples, and we’ll evaluate your parts to determine whether rack or barrel plating is the right fit.
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With 210,000 sq. ft., we process full truckload orders efficiently, keeping parts organized and on schedule with dedicated staging, processing, and tracking.
Flaking, bleed-out, poor adhesion, we catch plating issues early before they turn into costly problems.
From fast quotes to clear answers, we simplify the plating process so you can focus on the rest of your project.
Contact Our Plating Experts
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