We all crave for some change once in a while, and when it comes to changing the look of your house, airless paint sprayer is the best option to go preferred. From industrial painting to infrastructural projects, airless paint sprayers are used in almost all areas in different ways. But have you ever been curious to know how these little tools work so efficiently that we don’t need rollers or brushes for the paint job anymore? If yes, you have just reached a right place. Here we will tell you all about airless paint sprayers including their working and components. Now you will know everything about the tool you use to accomplish DIY projects.
How Does an Airless Spray Painting System Work?
It is a widely asked question, “How to operate an airless paint sprayer?” So, here is a quick explanation of it. Fluid viscosity and surface tension are the two factors that work together to achieve the goal of fluid adhesion, while atomization technique is used to improve the paint application by dissipating the mass of fluid into small and even droplets. Now in an airless system, intense energy is produced through high pressure that is then injected into the paint to increase the atomization.
Once the paint is atomized, it is pushed to the hose to discharge through the small tip of the spray gun in the form of a beautiful stream. As soon as it comes in contact with the air, the flow is dispersed into smaller droplets before landing onto the surface.
It is the tip size of the spray gun that determines amount fluid to be released and fan pattern to be followed during the application. You may choose tips with different orifices for different sort of tasks.
What is Airless Paint Sprayer
Francis David Millet is the name of the person who invented the very first spray painting device with basic functioning in 1892. Later, the smart Edward Seymour modified this device and introduced a modern version called aerosol spray. Since then, different types of paint sprayers have been invested that you may classify into two groups, air sprayers, and airless sprayers. Today we will only focus on the latter one.
Airless spray painting equipment is a spraying tool that provides smooth and even coating for the surface. As the name suggests, airless sprayer doesn’t use compressed air to atomize the fluid into small droplets for uniform application. Its functioning is determined by two factors, the tip size, and pressure. In an airless sprayer, the fluid pumps out through the nozzle under high pressure. In addition to strength, the tip also creates spray pattern. While on the other hand, air sprayers work with compressed air that is injected into the stream of fluid to cause atomization.
There is no doubt that airless sprayers provide flawless coating results and allow users to enjoy quick applications. It is because airless sprayers are efficient enough to deal with varying fluid viscosities. The high-pressure fluid stream in airless sprayers provides sufficient energy to overcome the viscosity and surface tension. This feature enables the fluid to cover the surface smoothly in an even manner.
The fluid comes out with higher pressure from the tip of the airless sprayer and forms a fine layer over the surface. Every droplet lands with force and integrates firmly to create a smooth coat. The tip size and pressure determine the level of fluid flow. You can adjust both of these features to enjoy desired results.
The advantage of Airless Paint Sprayer
Airless paint sprayers have many benefits that make them ideal for small and large painting projects. They are perfect for onsite painting because you can carry them anywhere easily. There are hardly any airless sprayer models that weigh more than one hp.
Airless paint sprayers are versatile tools that you may use to accomplish indoor as well as outdoor projects. From painting wooden doors to retouching metal cladding roofs, you can use an airless sprayer for a variety of projects.
When it comes to recoating projects, there is no best option than using an airless sprayer. Saving up to 75% of labor time, you can apply an even coat four times faster and smoother than a paintbrush or roller.
Most people prefer HVLP sprayers, but they are not suitable for large-scale projects. Airless paint sprayers are quite efficient in covering larger surfaces quickly and smoothly. Now you don’t have to waste the whole day in repainting a single fence!
Unlike brushes and rollers, airless sprayers don’t miss any spot and cover the surface evenly. The high pressure fast flowing fluid lands on the surface in a whip and coats it smoothly.
When you don’t want to replace the damaged piece but only need to retouch, use an airless sprayer that provides a magical coat to cover the rough and damaged texture.
Airless sprayers provide thick and even coats, so you don’t have to apply multiple layers for desired results. It will save your time, material and efforts.
The flawless finish an airless paint sprayer offers cannot be achieved with the use of any other paint application tool. In less time with fewer efforts, you can enjoy a glass-smooth layer of coating.
When using an airless sprayer, you are not bound to work with specific materials. From electrostatic to water-based to latex paints, you can use the airless sprayer to apply any fluid.
Airless sprayers apply wet coatings that adhere quite firmly to surface and form an active, even layer of paint. Such a good adhesion results in the long-lasting coating.
Airless Paint Sprayer Components
An airless paint sprayer consists of different components. Each one of them has its efficiently roll in improving the working of the tool. All parts work together to achieve the goal of paint application. Here we will discuss the components of an airless sprayer and their functions. To understand the working of this tool, it’s necessary to develop an apprehension towards its parts functioning. Let’s begin with the first component:
Comparing to the traditional airless, the fluid in an air-assisted airless is passed to the gun at more comfortable low pressure, somewhere between 500-1500 psi. As the fluid passes through the tip, it is partially atomized into small droplets. Experience atomization takes place when a small amount of air ranging from 5-35 psi is added to the edges of the spray fan. It results in a smoother application, reduced overspray and high transfer efficiency. It’s also a controlled atomization that allows users to adjust the flow according to their convenience.
The spray tip and air cap of an air-assisted airless sprayer control the amount of fluid sprayed and add air into the spray fan. The gun works as the on-off valve that manages the flow of the liquid. The air adjustment valve enables air to reach tip as close as possible for a softer application. The hose is used to transfer the fluid from the container to the gun while motor system enables the pump to perform. There is also a digital display that allows users to regulate the fluid pressure according to project requirement. Air-assisted airless also has an air compressor that delivers air to the gun.
Airless Spray Gun Tips
An airless spray tip plays an integral part in paint application. It is responsible for determining the fluid flow and also used to adjust the spray pattern to apply fluid in a right direction.
It’s not wise to use a worn out tip. A shabby spray gun tip has a bigger orifice and decreased fan width. These factors affect the spray pattern significantly. If the fan is not working like before and providing poor pattern results, it’s time to change the tip. Continuing working with a poor spray gun tip results in higher overspray, material loss, and low-quality paint application.
For instance, if a tip with 12-inch fan pattern wears out, the design will reduce to 8-9 inch fan, resulting in 40% more paint application on 25% less surface. This situation will lead to increased material loss and overspray. You will repeatedly overlap for consistent thickness, but it will only ruin the look and make it appear uneven. This chart above illustrates the effects of a worn-out tip on spray pattern.
There is a variety of airless spray gun tips in the market graded according to the size of the orifice. When it comes to choosing the best one, consider the type of project you want to accomplish. Some project requires little application while some involve too much of it. You have to make sure that the tip you choose is compatible with your project requirements. Also, check if your preferred spray gun tip is suitable for your airless unit or not. Although you can use multiple spray gun tips with a single airless unit, it’s always safe to check it ahead.
Spray tip selection can also be made from coatings. Small tips are ideal for light surfaces such as enamel and stain while large tips are perfect for thicker coats that involve the application of latex paints. Consider your project type and coating goals; you can choose a fine spray gun tip for your airless unit. One thing you need to understand is that spray gun tip never lasts longer and you cannot use a worn out tip to achieve desired results.
Airless Spray Pumps And Motors
Almost all airless sprayer models have a pump that is used to regulate fluid flow. The fundamental function of a shoe is to deliver an even flow of liquid through the hose under high pressure. It is powered by three sources, electric motor, compressed air, and gas engine. The electrical and gas powered pumps come with a motor that generates a continuous rotation with crankshafts and connecting rods. There are also hydraulic powered pumps that operate when hydraulics are used to transfer the power. While compressed air motors work with the flow of air causing piston and rod to move upward and downward.
When choosing an airless sprayer, you will come to know about four different types of motors: Universal, AC, Dc and Brushless Dc. Here we have provided a quick comparison of all four models regarding advantages and disadvantages.
|Universal||The most significant advantage of universal motors is that they are pretty cheaper to manufacture while AC and DC motors are comparatively expensive.||The universal motors wear out sooner due to shorter life expectancy. They run at 10,000 to 20,000 RPM hence even if the fan is cooled, the motor is not enclosed correctly.|
|AC||If used in a controlled condition with great care, AC motor is a long life product with higher durability.||The maximum length of the cord is 100 feet which are not sufficient, and it requires continuous power to operate.|
|DC||You can use longer extension cords up to 300 feet. It’s a forgiving motor that runs fine at variable power speeds.||DC motors are quite more large units and expensive as well. They are pro level!|
|Brushless DC||IT’s quite lightweight, efficient and compact. It allows the use of longer cord and generators and works perfectly with power fluctuations as well.||Although it’s small, it weighs more substantial than an AC motor and costs way expensive than a DC motor.|
Considering recent changes, DC motors have improved significantly. Due to an increased flow rate, Dc motors deliver higher output. Using them will save you from annoying tripping and allows to use longer cords efficiently. They are also pretty smaller hence lighter and more comfortable to move. Dc motors are quite safe to use due to no for sparkling as they run cooler. The impressive horsepower of Dc motors allows them to perform awesomely with longer life. The fans in DC motors are appropriately enclosed, protecting the motor from getting stuck or rusted due to dust and dirt.
The gas engine uses horsepower to operate the pump while electrical energy powers the clutch. This system is called direct drive system. Sprayers with direct drive system are considered to be most efficient gas-powered units. Hydraulic sprayers also use gas engines to operate the hydraulic pumps. In such groups, the oil is drawn from a reservoir that is then pumped to the motor.
On the other hand, there are also handheld sprayers that follow the airless technology to operate. This airless technique is widely known as the ProSpray technology that allows painters and contractors to cover any surface efficiently with high performance. Handheld sprayers are electric and battery powered units that come in handy when it comes to attempting a small project including 1-3 gallons.
Nobody can deny the advantages of handheld sprayers. This type enables do-it-yourselfers to enjoy professional spray finish, easy portability, and quick cleaning. Setting up a handheld gun is also not a problem and can be done in minutes. Handheld sprayers are much similar to traditional airless sprayers due to inbuilt pump and gun. But handheld spray units are more efficient because they don’t require a hose that increases material waste and affects paint job.
Coming to the pump, it is one of the most critical components of an airless sprayer. Many contractors even call ‘Pump’ to the whole sprayer unit. In the market of airless prayer, you will find two general types of pump: Piston and Diaphragm. If you didn’t know much about these pumps and confused to decide which one is most suitable, check out this quick comparison explaining advantages and disadvantage of both types:
|Piston Pump||It is strong enough to pump high viscosity fluids with ease. The atomization is also impressive as it provides higher pressure at the tip orifices. You can use it for the hard level project and may add a longer hose for your convenience. It is also easy to repair, and the maintenance cost is low. The piston pump is suitable to accomplish smooth primes and flawless application.||Although its maintenance cost is low, the initial purchase price is quite high and not easily affordable. It doesn’t work well when set as low pressure to acquire more demand.|
|Diaphragm Pump||It comes with a range of pressures allowing users to adjust the settings and enjoy good pressure control. From low pressure to high demand, you can experience different flow rates. It supports high volume transfer of materials for texture application that helps in completing the task quickly. Unlike Piston pump, the initial purchase cost of this type is also pretty inexpensive.||This type is difficult to prime and has a higher maintenance cost. The biggest problem is that it is not strong enough to deal with high viscosity fluids resulting in spitting and improper application. This type also requires regular cleaning to perform well.|
Here is an explanation of the work carried out by double action displacement pump, the piston pump. It is a reciprocating pump that comes with two balls, inlet, and outlet balls. These balls are responsible for controlling the flow through the fluid section. To connect the internal component with the drive, a displacement rod is used. Following the action of the motor and drive the rod moves upwards and downwards accordingly. The material is loaded on the upstroke while displaced on both strokes confirming the little flow to the hose and gun.
Coming to the working of a diaphragm pump, it requires sprayer’s motor to generate the pulsing hydraulic pressure to operate the pump. The diaphragm goes up when intake strokes and upstrokes take place. When it pulls up, the partial vacuum is left behind in the paint chamber. This vacuum pulls the inlet valve to open and closes the outlet valve with pressure in the hose and spring. This is how fluid is drawn in the paint chamber.
Now, to discharge the paint from the chamber, the inlet valve remains closed while outlet valve is pushed open to flow the fluid into the hose. Comparing to a Piston pump, diaphragms have a small displacement volume hence it must run faster to operate correctly. It only delivers a steady flow of fluid if the speed is well maintained.
Airless Spray Hose
When it comes to choosing an airless spray hose, you will come across different lengths, diameters and pressure controls. These all factors should be considered to select the best one for long-term use.
The length and diameter of an airless spray hose determine the pressure of the fluid delivered to the spray gun. For instance, a more extended range and the larger diameter of a hose result in a higher strength of drops.
Consider the type of project and size of the airless sprayer to determine which hose length, diameter, and pressure suit you the most. If you are planning on using two hoses together with different diameters, make sure you attach the smaller diameter hose to the gun and larger diameter hose to the pump for minimal pressure drop.
Paint sprayers are not new for us and have been serving contractors and DIY painters for a long time. Although there are many types of sprayers, you may classify them all into two kinds, air sprayer, an airless sprayer. The technology used in airless sprayers is quite impressive in terms of speed and application. Different components including pumps, motors, tips and hoses work together to improve the overall function of an airless sprayer. The quick information above about the different parts of an airless sprayer will not only help you choose a right unit for your next project but also help you be informed on how does an airless paint sprayer work!