What is Dura Tech?

Dura Tech is a specially-formulated blend of chemicals. It is oil-based, but is more than just oil. Dura Tech contains several additives which inhibit ‘rusting’ (the corrosion of iron and steel).
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How does Dura Tech work?

When Dura Tech is sprayed on a metal surface, it displaces existing moisture from that surface. Dura Tech contains chemicals which then ‘adsorb’ (not absorb) or bond to the metal surface, making it difficult for water to re-contact the metal. If moisture does not contact the metal, then corrosion will not occur.
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What Dura Tech will and will not do.

Dura Tech will displace existing droplets or thin layers of moisture when sprayed onto surfaces. Consequently, Dura Tech is still effective when applied to slightly wet surfaces. In contrast, simple oil sprays or tarry substances do not displace existing moisture from surfaces, and in fact can trap existing moisture in contact with the metal.

Dura Tech will not normally displace large pools or puddles of water. Any large build-ups of water in the trunks, body cavities, etc., must be drained before spraying.

Dura Tech will penetrate into, and displace moisture from crevices formed by seams, cracks, and other tight spaces. Moisture tends to accumulate in these areas, making them prone to rusting. Note that tarry products will not ‘creep’ into tight spaces. Dura Tech will also penetrate into cracks or other imperfections in sealant coatings, and thereby protect the exposed parts of the underlying metal.

Dura Tech will not penetrate through build-ups of ice and mud under vehicles. Any build-ups of ice and mud under vehicles must be thoroughly cleaned off before Dura Tech is applied.

Dura Tech is designed to protect against rusting of sheltered areas, such as inside the body panels and inside folds and crevices. Our warranty only covers rusting ‘from the inside-out’, and customers are advised to take care of the paint on their vehicles in order to prevent ‘surface rusting’.
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Surface Rusting?

Surface rusting refers to the rusting of body panels from the outside surface. A good quality adherent pain twill normally protect against surface rusting.
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How does paint protect the underlying steel from rusting?

A sound paint film acts as a barrier to charged ions, such as sodium and chloride ions from dissolved salt. If the ions do not contact the underlying steel, then rusting will be inhibited.

Although the paint is permeable to water and oxygen, it restricts their sideways movement across the steel surface, thereby inhibiting rusting.
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How can a paint film fail?

Problems can begin if dissolved road salt gets between the paint and the steel. This can happen if, for example:

• there are pinholes (holidays) or voids in the paint.
• the paint gets scratched or chipped.
• the metal surface wasn’t properly cleaned before painting.
• salty deposits are allowed to sit on the painted surface for a long time, (example, salty caked-on mud). Given enough contact time, dissolved salt will eventually penetrate through the paint.
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Once dissolved salt has penetrated to the metal surface, then :

• Water (rainwater) on the outside of the pain twill tend to migrate through the paint nature will try to even out the concentrations of salt on the inside and outside of the paint. The movement of water creates an osmotic pressure beneath the paint, which reduces the flow of water, but also pushes out against the paint film, causing blisters.

• Since oxygen can pass through the paint relatively easily, rapid rusting of the steel can begin. The rusting reactions usually product hydroxyl ions (alkali) which can react with the paint (if it is not ‘alkali resistant’) causing softening of the paint and loss of adhesion, and allowing the blisters to spread out.

• If the problem is left untreated, rust builds up and the defect in their point spreads by lifting the paint, resulting in undercutting during alternate wet dry cycles. Rusting of the exposed steel occurs in the condensed phase during wet periods. The resultant rust is deposited during dry periods, and once deposited, cannot easily be re-dissolved or dispersed on rewetting. Consequently, a rust scale builds up between the paint and the steel, effectively separating them, and exposing the underlying steel. If the damaged area then still remains untreated, accelerated rusting and eventual perforation of the steel can result.
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Localized Corrosion – the result of untreated paint damage.

The failure of a paint coating can, in many instances, result in rapid rusting through of a vehicle’s body panels, especially in the presence of chlorides from road salts.

The rusting of the metal is ‘localized’ resulting in deep penetration into the steel over an initially relatively small area exposed at a defect in the paint.

Localized corrosion can continue and accelerate under build ups of rust. In such cases, a ‘differential aeration cell’ can be set up, in which oxygen reacts with water at the relatively easily accessible top steel surfaces, and the steel corrodes underneath the rust build up, which hinders access of oxygen from the air. The situation is aggravated by build up of chloride ions and acidity in the stagnant area under the rust. This process can potentially cause rapid perforation of auto body panels. For example, in one study, localized corrosion was found to penetrate into unprotected (unpainted) steel to a depth of 0.8 to 1.9 mm after one winter of typical driving in Hamilton (3). Given that auto body panels currently average about 2.2 mm in thickness, one can appreciate that rapid perforation is possible.
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What can be done to prevent Surface Rusting?

Wash vehicles well and regularly to prevent prolonged contact with deicing salts.

• Apply wax before the winter season.
• Touch up paint blisters or stone chips promptly.
• Repair any rust spots as soon as possible. A ‘rust converter’ can be used as a quick, temporary touch up for chipped areas that are beginning to show rust, however, a proper touch up should be done as soon as possible.
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