Glossary

Castings
New steel or iron castings are usually suitable for powder coating. It is worth contacting us if you have older castings.

Coating thickness
A one coat powder coating thickness is likely to be around 60 to 80 microns.  The combined thickness of an epoxy powder primer and top powder coat is therefore double this (around 120 to 160 microns).

Dress
See fettle.

Duplex coating
Two coating types combined, such as galvanizing over-coated with powder coating.

Epoxy
After polyester, epoxy is the second most popular powder coating resin we offer. Epoxy offers especially good chemical resistance but is not usually suitable for outdoor use as it is not as UV stable as polyester.

Fettle
When we galvanize and powder coat, we ensure that the galvanized coating is fettled smooth before powder coating takes place. Also referred to as dressing or linishing. We only fettle our own galvanizing prior to powder coating.

Gassing
Galvanized steel emits gasses when subsequently heated up in a powder coating oven. If not treated these gasses can escape through the powder coating creating little bubbles in the powder coating surface. Our powder coating powder contains a ‘de-gassing’ ingredient to help greatly reduce such instances.

Gloss level
Most powder coating colours are available with a choice of gloss levels or sheen. The main ones are matt (approx. 30% gloss) sometimes called satin, semi-gloss (approx 60% gloss) and gloss (approx 80% gloss). The most popular is 30% gloss.

Grit blasting
See shot blasting.

Marine standard powder coating
This refers to the powder coating system often specified for steelwork that is to be located on the coast (and therefore subject to the harsh, corrosive conditions).  Marine standard powder coating is where the steelwork is first hot dip galvanized, then this is sweep blasted followed by the application of an epoxy powder primer and finally a top powder coat. Please contact us for more details.

Moveable parts
Adequate clearance must be left between surfaces for hinges etc if they are to move freely after powder coating. An extra clearance of 2mm is usually sufficient.

Polyester
Most powder coatings we offer are pigmented polyester resin. It offers some corrosion resistance and is UV stable (good for outdoor use). Compare epoxy.

Primer
In powder coating, where the steel is located outside but galvanizing is not appropriate, we recommend that we first apply an epoxy powder primer before powder coating the ‘coloured’ top coat. The primer will help protect the steelwork from rusting.

Repair
Repairing scratches in a powder coat can be done using a colour matched tin or aerosol paint. Please contact us for details.

Rust
Iron and steel are prone to oxidisation. Protect your steel with the appropriate powder coating system.

Shot blasting
We shot blast using chilled iron grade G17. The steel is blasted with iron particles to either clean the surface of impurities such as old paint systems, oil, grease etc or to ‘rough’ up the surface to prepare it for powder coating and in some cases galvanizing.

Stainless steel
We can powder coat stainless steel.  Please contact us for details.

Standards
The British standard for powder coating galvanized steel is BS EN 13438 (2005).

T-Wash
A chemical etch applied to a galvanized coating to key it ready for the powder coating process.

Warm to touch
A plastic powder coating that is usually much thicker than the standard polyester coatings. The plastic powder offers good thermal insulation making it ideal for handrails. It also has good chemical resistance.

Welding
Raised weld seams can occur during galvanizing (when a thicker zinc coating results on the welds than on the steel around it). To avoid this it is recommended that the silicon content of the welding rod material be less than 0.04%.  Please be aware that if raised weld joints/seams occur after we have galvanized your steelwork, we will not fettle these down prior to powder coating as standard.  Please contact us for details.