Neutrarust 661


Rust Converter & Primer​

The Original Rust Converter developed over 40 years ago and still recognised around the world as the best rust converter for almost any rusted metal.

Neutrarust 661 ® – Technical Data Sheet

All ferrous metals corrode unless continually protected. The process is a complex action which always involves the availability of moisture and oxygen. This persistent, destructive and degenerative process is accelerated by associated surface contaminants such as mineral salts and acids. Only by absorbing or neutralising surface pollutants and completely excluding moisture and oxygen from the metal surface can an adequate long term protective system be achieved. Ultimately, rusted objects can become unsafe and unusable. Many rust control processes are only partially successful because they do not cope adequately with all three basic causes of ferrous metal corrosion: the elimination of surface contaminants, the removal of free moisture and oxygen from the metal surface and the protection of the treated surface by an impenetrable membrane.

Neutrarust 661® – The Revolutionary Complete Rust Treatment System

Is a unique corrosion control system developed for use on rusted ferrous metal surfaces. The ferrous surface to be protected is converted on contact to a black, complex organic iron compound by the unique deoxygenating agent incorporated in the Neutrarust 661® converter. This corrosion resistant layer is formed by utilising all the surface moisture and oxygen during the reduction reaction. Concurrently, the special copolymer latex emulsion covered system and dries to form an impermeable barrier to oxygen and moisture.

Neutrarust 661® is a white organic copolymer latex that dries on rusted surfaces and chemically converts these to a ready to paint non-tacky layer in 30 minutes under normal conditions, forming an independent complex iron/iron-oxide/organic chemical compound which gives complete protection for the treated surface. The continuous chemical curing of Neutrarust 661® forms a chemical bond with every metal interface, pacifying, neutralising and chemically converting rust. The ready to paint chemical compound layer is completely neutral and can be used as a primer, without further treatment, for standard or synthetic resin lacquers, oil-based paints, two-component lacquers or bitumastic and oil tar-based finishes including micaceous iron-oxide paints. Neutrarust 661® is non-toxic and does not contain phosphoric acid or lead.

Neutrarust 661® has approvals from the British Ministry of Defence and NATO

Neutrarust rust converter process


Important – It is recommended an initial test area to be tried at all times, in the working conditions with the other materials being used to ensure compatibility of Neutrarust 661® with the rust surface being treated including the top paints to be used for over coating etc. Remove any loose flakes or high spots of rust, loose or blistered paint using a wire brush or scraper. The surface to be treated should be free from oil or grease deposits. Salt must be removed using a suitable detergent and fresh water. It is not desirable to remove all traces of rust.


Surface temperature at application should be above 5°c and below 40°c. Stir well before use and transfer a quantity of rust remover into a non metallic container for application. Apply the using a brush, roller or airless spray equipment. Work well into deeply pitted areas using a brush. Ensure all areas of corrosion are covered. Do not pour the unused rust remover back into the original container, as any contamination could degrade the fresh product. Depending on the condition of the surface, up to three coats may be required to ensure complete coverage and conversion of all corrosion present.

Drying Time

Depending on temperature and humidity, touch dry in 20-45 minutes. Do not apply additional coats for at least one hour after the previous coat is dry to touch. Do not allow the coating to get wet whilst drying. Allow to cure for 24 hours before applying overcoat. Test compatibility before use.

Covering Capacity

This is dependant upon the application method and the condition of the surface. Coverage will be reduced on very rough or pitted surfaces. An application of a wet film thickness of 50-100 micron should up to 12 square metres per litre.


Neutrarust 661® should not be applied to cold metal below 5°C or hot metal above 40°C. But will withstand temperatures between -40°C and 60°C when dried hard. Store between 5°C and 35°C. Not to be used or stored outside of recommended temperatures. Use within 12 months of opening. Replace cap after use. Use in adequately ventilated area. Gloves and goggles are recommended. Do not store in direct sunlight.

DRYING TIMES – Each Coat Touch dry—summer approx. 15 minutes, winter approx. 45 minutes. Between coats: summer and winter approx. 12 hours. Protect from rain during drying!

CLEANING BRUSHES OR SPILLAGE Use detergent water wash and rinse with water or industrial solvents.

Neutrarust 661® MUST NOT BE SWALLOWED If swallowed, wash out mouth with water and give water to drink. If in any doubt as to effectiveness of treatment, obtain medical attention immediately. Harmful by inhalation treat symptomatically. Eyes: splashes to the eye should be removed by washing with eyewash solution or water for at least 10 minutes. Skin: splashes should be washed off with water and soap as soon as possible. If in doubt in any case obtain medical attention immediately.

P280: wear protective gloves & eye protection!

EUH210: Safety data sheet available on request!




Manufacturer Safety Data Sheet (MSDS) available on request.

Neutrarust 661



Copyright © Neutrarust 661 | All Rights Reserved 2021

Neutra Rust Europe Limited, 4 Comet House, Calleva Park, Aldermaston, Berkshire, RG7 8JA

Telephone: +44 (0) 118 206 7788

Neutrarust 661® Registered Trade Mark of Neutra Rust Europe Limited