Powder Coated Springs and E-Coating 

Partnering with U.S. Spring Manufacturers Since 1974

Springs are not ordinary coating jobs. They flex, compress, twist, and cycle under load, and their finish must protect the metal without compromising performance. Winona has decades of experience working with area spring companies, and that experience has given us spring-specific knowledge and a clear understanding of how to get the best results.

Why Springs Need Specialized Finishing

Springs are made from wire and strip with tight geometry, small gaps, and repeated movement. Coils can trap contaminants during pretreatment, coating can bridge between turns, and poor adhesion can lead to flaking as the spring flexes. Corrosion can also affect appearance, performance, and service life.

• Spring-specific pretreatment for strong coating adhesion
• Protection against rust and corrosion in demanding conditions
• Coating options suited to flexing and repeated cycling
• Consistent coverage across coils, ends, and wire forms
• Wide color choices for branded or identifiable products
• Powder coating, E-coating, or combined systems
• Quality certifications and documented processes
• Fast turnaround for spring production schedules

Winona has perfected the correct pretreatment for springs and offers a wide array of spring-appropriate powder options. We work with manufacturers to review wire size, spring type, material, expected movement, operating environment, and finish requirements before recommending a process.

E-Coat for Corrosion Protection

E-coating is an immersion process that helps coat tight areas and complex shapes, especially valuable for coil springs and wire forms where spray coverage can be inconsistent.

• Thin, uniform coverage
• Strong corrosion protection
• Coverage in tight coils and hard-to-reach areas
• Efficient processing for higher volumes
• A standalone finish or a primer beneath powder coating

Our E-coat service features the industry-leading Axalta 6100 series polymers. Winona's E-coat line includes a 13-stage pretreatment process with laser scale removal, zinc phosphate, and RO water.

E-Coat Primer + Powder-Coated Topcoat

Winona's Etna Green facility is rare in offering powder coating and E-coating under the same roof. Powder coating provides protection in harsh conditions, and E-coating provides corrosion protection. Combine them for the ultimate protection.

For springs used outdoors, in wet environments, or around road salt and chemicals, an E-coat primer with a powder topcoat adds a second layer of defense. If the powder is worn or chipped, the E-coat underneath continues to protect the steel from rust and chemical corrosion.

The Winona Advantage for Coated Springs:

Local Spring Industry Experience

Winona has decades of experience working with area spring companies. That history gives us a practical understanding of what spring manufacturers need.

Correct Pretreatment and Powder Selection

We have perfected the pretreatment process for springs and offer spring-appropriate powders.

Certifications and Fast Turnaround

Winona is backed by the quality certifications, production methods, and fast turnaround that spring manufacturers increasingly require. We are ISO 9001 and UL certified and comply with automotive, agriculture, and military specifications.

Powder Coating and E-Coating Under One Roof

Our Etna Green, Indiana facility offers powder coating and E-coating together, giving spring manufacturers flexible options for corrosion protection and durability.

Regional Capacity and Experience

Winona is the largest provider of finishing services in the Northern Indiana and Southern Michigan region. We have served the finishing industry since 1974 and started powder coating in 1979. Our headquarters in Etna Green covers 167,000 square feet, and our second facility in Elkhart covers 50,000 square feet.