Conventional guns have a transfer efficiency of approximately 45 per cent but HVLP spray guns transfer more paint to the job and reduce emissions of volatile organic compounds (VOCs). Now all the talk is HTE guns. Anest Iwata's Karl Isherwood explains.
CONVENTIONAL SPRAY GUNS have been in use for a long time and are still widely used in the marketplace. As a general rule, these guns are more common for uses such as general industrial coatings, some basic furniture and timber coatings and the home handyman areas.
Typically, a conventional spray gun consumes approximately 12 cfm of air and operates at 50-60 psi inlet air pressure. The transfer efficiency, or how much paint actually stays on the job, is relatively low at around 45 per cent – with the remainder of the paint product exhausted into the atmosphere.
In an attempt to improve both transfer efficiencies and reduce costs, in terms of energy usage, paint wastage and the emissions of VOCs, further development of the spray gun was required.
The first results were HVLP (high volume, low pressure) spray guns. HVLP specifically refers to the fact that the air pressure inside the air cap must be no higher than 10 psi during the spraying process.
Very early developments, approx 50 years ago, were derived from the household vacuum cleaner where a paint container was attached to a hose on the blower side of the machine. Since then this technology has undergone very significant change.
A full range of HVLP spray guns is on offer from Anest Iwata. Better known spray guns in this series include the LPH100 and LPH400 range. On release, the LPH100 was believed to be the first high performance, compact, lightweight HVLP spray gun in the automotive refinish industry. The LPH400 is the HVLP spray gun of choice for many in the automotive respray industry today.
The most recent addition is the LPH80. A compact centre feed gravity spray gun, it is perfectly suited for use in touch-ups and small area spraying like custom graphics and for use with candy colours. Continual investment in research and development by Anest Iwata has resulted in two new spray guns for the users of this HVLP technology.
Both the LPH400 LVX and the LPH40LVX feature the newly designed Anest Iwata eXtreme air cap technology and are easily recognised by the purple and orange air cap rings.
These guns have been engineered for the spraying of pearl and metallic basecoats to overcome the difficulties that standard spray guns can face with mottling, blotching and streaking. With air inlet pressures as low as 10 psi and fan patterns as wide as 25.2 cms – at 10 cms from the panel surface – these guns are perfectly suited those looking to maximise production with little or no variation in spray technique.
With every paint shop searching for cost savings, more efficient methods and growing pressure for stricter compliance with environmental legislation, Anest Iwata developed a range high transfer efficiency (HTE) spray guns.
Released in the late 1990s, the High T.E.C. (Transfer Efficiency Control) range of spray guns takes HVLP to an even higher level. This range provides the user with unparalleled colour matching by utilising a flat and thin pattern shape and better control of atomising pressure.
Using between nine and 12 cfm of air for a standard refinish gun, transfer efficiencies of up to 90 per cent are being achieved, depending on paint type. For optimum results, these guns have been designed to operate at lower inlet pressures, typically around 2 Bar ( 28 psi). This low atomisation pressure, combined with the spray gun's flat and thin pattern shape, provides a more even cover of paint over the full pattern width.
It is this combination that provides superior results in finish quality and colour matching. The application speed is no different to that of a conventional spray gun.
Lower air consumption results in reduced energy cost – a big saving for any panel shop operation. More paint on the job, means less wastage and greater savings.
Reduced overspray also provides health benefits for the painter. As new technology paints are developed and released into the refinish industry, we have witnessed the move from medium solids to high solids solvent borne paints and the continued growth of water borne basecoats – it is of utmost importance that the spray gun is able to deliver the desired results.
The Anest Iwata W400 gravity spray gun has become the spray gun to use in automotive refinish spray applications. It allows the user to take full advantage of the latest in spray gun technology and has many features that other manufacturers are only now starting to include.
For those painters who are looking further into the future with the expanding use of waterborne coatings, Anest Iwata has developed the next generation in waterborne spray technology.
The new W400 WBX features a newly refined spray pattern and finer atomisation for even better results. No loss of production speed is another important advantage.
Enquiries: 02 9853 2000