FDC Rust Converter Ultra Rust Repair Spray 1 Gallon — Professional-Grade Rust Neutralizer & Primer, Fast-Drying

FDC Rust Converter Ultra is a professional-grade liquid that chemically transforms active rust into a durable, dark protective coating, stopping corrosion and creating a paintable surface.

If you need a faster alternative to sandblasting or extensive mechanical removal, this ready-to-use rust converter works on iron and steel to neutralize oxidation and form a sealing barrier. Designed for contractors, fabricators, mechanics and DIYers, the product simplifies rust repair on vehicles, railings, structures, equipment and marine parts. It’s formulated to act as both a rust neutralizer and an effective primer for oil-based topcoats.

How quickly does it stop rust and what surface prep is required?

The formula begins converting active rust on contact, producing a smooth dark finish within about 20 minutes. For best adhesion and performance, remove loose scale and heavy flaking with a wire brush or sandpaper, then degrease and clean the surface thoroughly.

• Remove large flakes and loose rust with a wire brush.
• Clean dust, dirt and grease before application.
• Do not apply if surface temperature is below 50°F (10°C).

How do I apply FDC Rust Converter Ultra and does it need thinning?

Shake or stir well and apply directly from the container — no thinning required. You can use a brush, roller or pump sprayer to cover the area; allow the first coat to dry, then add a second coat if needed to ensure complete conversion of heavily corroded spots.

• Ready-to-use: brush, roller, or pump-spray application.
• Dry-to-touch dark coating in about 20 minutes.
• Apply a second coat for thorough conversion on heavy rust.

What coverage and drying times should I expect, and can I paint over it?

On smooth, non-porous steel, one gallon covers approximately 500 square feet; rough or porous surfaces will need more product. After application, allow 48 hours cure time before applying a finish; this cured coating serves as a primer and should be sealed with two coats of high-quality oil-based paint for long-term protection.

• Approximate coverage: 500 sq ft per gallon on smooth surfaces.
• Drying: dark finish in ~20 minutes, full cure in 48 hours.
• No additional primer required before oil-based paint.

How do I maintain equipment and store leftover product?

Clean brushes, rollers and sprayers immediately after use with soap and water to prevent buildup. Store the container in a cool, dry place protected from freezing and from temperatures above 100°F; keep out of reach of children and avoid application on cold surfaces.

• Clean application tools promptly with soap and water.
• Do not store in freezing conditions or above 100°F (38°C).
• Follow local regulations for disposal of leftover product and containers.

Who is this for: FDC Rust Converter Ultra is built for professionals and serious DIYers who need a reliable, time-saving solution to treat and prime rusted iron and steel without elaborate equipment. It’s ideal for auto body repair shops, welding and fabrication shops, property maintenance teams, marine restorers and homeowners tackling fences, gates, trailers and outdoor metal fixtures. Choose this product when you want efficient rust neutralization that prepares surfaces for durable oil-based topcoats and long-lasting protection.