Powder Coating – The Best Option
When you want to paint or repaint something, you most likely have 2 important requirements; the finished product will look good, and it will last. Of all the coating options available to you, one painting system stands head and shoulders above the rest and is capable of achieving this; Powder Coating.
This painting method creates a fantastic beautiful coated finish that is resistant to scratching, fading, chipping and corrosion. The coating is literally chemically bake-bonded onto the surface of the part, creating an even protective film that is far thicker and tighter adhered than achievable with liquid coatings.
Every day you unknowingly come into contact with many powder-coated items: household appliances, furniture, lighting, outdoor playgrounds, bus handrails, bicycle frames/parts, car and motorcycle alloy wheels etc. All these require a tough wear-resistant durable attractive finish that is made to last. Powder coating is by far the best method to achieve this.
Shoot the Powder
As its name suggests the coating starts as a powder. This is gently applied, through a spray gun, onto the surface of the item to be coated. To get the powder to stick to the part, and not immediately fall off, the powder is charged with a positive electrical charge as it passes through the gun. The item to be coated is earthed to ground and thus becomes negative. As opposites attract, these opposing charges ensure the powder is fully attracted to the workpiece and adheres tightly to the surface.
This method of electrostatic charging the paint particles leads to very high transfer efficiency and does not create large amounts of overspray or paint wastage. The electrostatic charge gets the paint into every area, including internal areas, that require coating to ensure your item is fully coated with an even paint film covering the whole surface. Even difficult-to-access or see areas are fully covered.
Applying the powder to the surface is the first half of the process. Now the powder has to be converted from dry powder particles, electrically stuck to the surface, into a tough, even smooth coating covering the whole surface without sagging, runs or other defects.
To achieve this the parts are placed into a preheated gas-fired oven and held at curing temperature for a time suitable for the coating and substrate. With both the powder and the workpiece at the correct temperature, the powder will slowly melt and cross-link into a semi-liquid state which then solidifies to form a smooth even skin over the surface of the part.
Some applications require several full or semi-cure cycles to achieve the desired result. The digitally controlled temperature oven we use for powder coating curing accurately maintains the correct temperature during the curing cycle. This accuracy ensures perfectly cured coatings are achieved on every part we process.
Upon completion of the melt and curing the parts are left to cool down, before QC inspection and testing for defects.
As with many processes, the key to a successful outcome is attention to detail in the preparation. Although it is a relatively simple process, powder coating relies on many parameters all being correct and accurately controlled. Screw up one small step will likely lead to a poor quality coating or complete coating failure.
One of the most important factors is the preparation of the parts’ surface prior to powder coating. The parts need to be 100% clean and have the correct surface profile and roughness for the coating to adhere tightly to. Dirt and oil on the surface will bubble through the coating during curing. Incorrectly prepared surfaces are too smooth for the powder to bond and grip onto.
We pay particular attention to the quality of the parts’ surface before powder coating. As a 20-year-old abrasive blasting contractor, we have a very long history in abrasive blasting and the use of various abrasive types for differing applications and requirements. All parts we process are thoroughly blasted with the correct abrasive type and size to suit the requirements of the powder, application and finish. After blasting the parts are further processed to ensure they are 100% clean and contaminant free before applying the powder coat.
All the Colours of the Rainbow
Gone are the days when you can only select from a dozen or so industrial colours, that belongs in the 80’s. Today there are virtually limitless colours to choose from. Our powder material principle is Colombia Coatings USA. They have a range of over 1,500 different colours to choose from, with more being added every week.
Aside from the huge variety of colours available, another advantage of powder coating over other coatings is the range of finishes and effects that are available. Not everything has to be a plain flat colour. We can achieve the following beautiful appearances; Glossy, Satin Semi-Gloss, Matte, Chameleon / Color Shift, Metallics, Dormant / Illusion, Aftershock, Rumble, Textures / Veins / Elegant etc.
With such a huge range you are sure to find something to meet your coating or recoating requirements.
We have a fully fitted out powder coating facility in order to conduct Powder Coating in Singapore.
Feel free to contact us with your powder coating requirements.