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WHAT IS POWDER COATING


Powder coating is similar to paint but has some big differences to its application as well as the finished product. Powder coating is applied as a free-flowing dry powder instead of a liquid and it utilises an innovative electrostatic spray gun process. This electrostatic process works in a very similar way to magnetism with positive being attracted to negative etc. The powder becomes electrostatically charged up by the spray gun and is released as a fine spray of electrostatically charged particles. These particles are attracted to the metal item which has an electrode attached. This works by pulling the positively electro-charged particles to the whole of the negatively charged metal item and ensures all of the area is covered with the powder coat. This innovative method works very efficiently and can be seen visibly pulling the electro-charged powder coating from the air surrounding. The powder spray will even cover the sides of the item when being sprayed from the front. This gives many benefits and helps with a deatiled, even cover and a perfect finish.


Another big difference between a conventional liquid paint and powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension form. The coating is typically applied dry utilising its electrostatic method and is then cured under heat to allow it to flow and form a "skin". The “skin” once set leaves a very hard wearing, extremely durable coating that will last for many years. As with any paint or powder coated item its durability is down to conditions such as being exposed to bad weather, water, salt, chemicals, U.V light and after care. If its durability were to be compared to paint in general, it will always last a lot longer. In general items that have been coated for external use with the correct powder coating will have 20 years+ durability and usually last longer for indoor applications.

 
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PREPARATION

The first part of the process to be considered is the stripping of any electronics, electrical wires, plastics trim or anything that will not be able to withstand any part of the process. This item should be able to withstand processes such as being shot blasted, dipped in chemicals, powder coated and cooked at temperatures up to 200C for a period of 10 – 15 minutes. The stripping of everything besides the item/ shell that is to be powder coated is essential and should be done with great care. All bolts, nuts, bearings and clamps should be removed and all threads for screws, bolts and nuts  should be covered or well lubricated using carefully placed grease or alike. The second part of preparation before the coating is the cleaning of any dirt, rust or existing paint and will be done in different ways depending on the type of metal to be coated.

 

SHOTBLASTING

What it is and services we offer

Shotblasting is a method used to clean, strengthen (peen) or polish metal and is typically done in a blast room. The blast room is a three part system; the containment structure, the abrasive blasting system and the dust collector. Most blast rooms will have a recycling system. This can range from manually reclaiming the abrasive blast using a shovel to reclaiming floor systems that convey the abrasive back into the shot blast tank prior to recycling. Shot blasting is used in almost every industry that uses metal, these include aerospace, automotive, construction, foundry, shipbuilding, rail, and many other industries.

 

PRIMING

Different methods

Aluminium etch primer


Etch Primer is a paint that is designed to physically bond itself to the substrate to which it is applied.  This is achieved by combining an acid with the paint so that the acid microscopically etches the surface of the substrate, thus forming a physical and chemical bond between the two. In most cases a colour will be added to the Etch Primer so that it can be seen. Acid Etch primer can also be used on steel although the acid properties are more suited to Aluminium.


Steel zinc primer


Zinc rich primers are used to protect steel and iron surfaces from corrosion. Unlike some primers which resist corrosion by forming an impermeable barrier between the metal and atmospheric moisture, zinc rich primers provide corrosion protection by electrical means. The zinc and the steel form a tiny electrical cathode type cell that protects the steel at the expense of the zinc. Of course the zinc primer also provides a little ‘barrier' protection as well as a good surface for powder coating. Some types of zinc rich primers (inorganic) are used as a standalone coating, but often they are top coated with a powder coated finish.

 

01704 841001 / 07544808332

8 Heatons Bridge Rd
Scarisbrick, L40 8JG

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