Understanding Electrostatic Spray Guns
Understanding Electrostatic Spray Guns
When you are looking to buy an electrostatic spray gun you will probably be confused right away, many dealers in Australia have little knowledge, don’t stock electrostatic spray equipment and will usually have to get representation from the manufacturer to assist. You will then find that the sales or technical representatives from the manufacturer will have limited experience, so who do you call?
AA Spray is a leading stockist of electrostatic spray painting equipment specialising in Ransburg electrostatic spray systems. We hold the entire range of Ransburg electrostatic spray guns in stock including the Vector R90, Vector AA90, Solo AA90, Ransflex RFX, Ransflex RFXi Indirect Charge and the famous Ransburg No.2 Deuce process hand gun.
Ransburg invented the electrostatic spray gun in the 1940’s and have been leading the industry ever since. Ransburg electrostatic spray systems are the most popular, widely used and have the most diverse range of electrostatic spray guns and systems in the world.
In this blog we will only be talking about manual pull (trigger) hand guns, automatic electrostatic sprays guns are rarely sold in Australia.
Types of Electrostatic Spray Guns
Electrostatic spray guns are divided into two categories –
1) 240V Corded Electrostatic Spray Guns
These types of systems have a 240v voltage supply box and 10m power cable that connects to the electrostatic spray gun. Corded systems are available in low pressure and high pressure spray guns but the main advantage of a corded electrostatic spray system is the consistent voltage to the electrode of the gun.
Low Pressure Corded Electrostatic
The Ransburg Vector R90 is a low pressure corded electrostatic spray system. Low pressure electrostatic spray guns are very much the same design as conventional air spray guns but they charge the paint as it leaves the gun. Low pressure systems will require either a pressure pot or a double diaphragm pump to supply paint to the gun. You will also require a 12cfm air compressor with a filter regulator to supply the power box and gun with compressed air.
Low pressure electrostatic systems like the Ransburg Vector R90 are ideal for on site work, it can be run from 240v power for both the voltage control box and the 12cfm air compressor which is big enough to supply air to the R90 gun. Pressure pots are more commonly used over double diaphragm pumps to supply the paint to the gun and if you are spraying a 2K product you will find it easier using a 10 litre pressure pot. The 2K product can be mixed in a four litre can and then placed inside the pressure pot to reduce mess and save cleaning time and thinners.
The Ransburg Vector R90 can be used for a wide variety of applications such as spraying metal stairs, door frames, aluminium windows, lift doors, garage doors and flat metal surfaces.
High Pressure Corded Electrostatic
The Ransburg Vector AA90 is an air assisted electrostatic airless spray gun that can be sprayed up to pressures of 2800psi through the airless spray tip. The Vector AA90 has a 240v voltage control box supplying power to the gun via a 10m cable. It will require an airless sprayer to supply the paint to the gun and you will also require a 12cfm air compressor to supply air to the gun.
High pressure electrostatic sprayers can be used for both on site spraying and fixed location workshop applications. If using the Vector AA90 on site you would require an electric airless sprayer to supply paint to the gun, the viscosity and the type of the paint being applied would determine the size of the airless sprayer to be used. For spraying in a fixed location such as production line or in a designated spray area you may only require a pneumatic air driven airless sprayer such as an Atomex XM-30 or a Binks MXL 32:1 airless sprayer but this would depend on the paint material being sprayed.
High pressure corded electrostatic sprayers have an extremely high transfer efficiency rate, they can spray thicker paint materials without the need for thinning, spray large area’s very quickly while making significant reductions in over spray. These types of systems are very good for workshop painting applications where you do not have a spray booth and you are spraying large steel fabricated items such as truck chassis, gantry cranes or any large fabricated steel objects with irregular or difficult shapes. The electrostatic charge combined with high pressure airless spray will give you superior coverage and wrap on most objects being sprayed.
2) Air Driven Turbine Electrostatic Spray Guns
Ransburg RFX are air driven turbine electrostatic spray guns that do not require 240v power or a power supply box, the gun operates only on compressed air that spins a turbine within the hand gun. The internal turbine generates the electrostatic charge to the electrode after the fluid nozzle.
Air driven turbine electrostatic spray guns require at least 17cfm of free air delivery to just power the turbine and you still need a little more air that flows through the air cap. These guns are generally not suitable for on-site electrostatic spraying unless you have a large air compressor with at least 24cfm free air delivery. They will not work with any 240v air compressor, you will not have enough air flow to make the turbine spin and you will not generate any electrostatic charge to the electrode.
Air driven turbine electrostatic spray guns are designed for spray booth, fixed location and production spraying where you have adequate and consistent compressed air supply. These guns require only a fluid hose to supply paint to the gun and a grounded air hose to supply compressed air to the gun. Grounded air hoses have a grounding cable at one end which is designed to be connected to a grounding point away from the job being sprayed. Many people think that the grounding cable should be attached to the material being sprayed in a similar fashion to an electric welder, this is wrong and if you read your instruction manual it will show you a diagram explaining the set up.
The main advantage of air driven turbine electrostatic spray guns is that you do not require 240v power, a voltage controller and you have only two hoses attached to the gun, one for fluid and the other air via the grounded air hose.
Air driven turbine electrostatic guns are available in low pressure versions like the Ransburg RFX which only requires a pressure pot or double diaphragm pump to feed the paint and they are also available in a high pressure guns such as the Ransburg Solo AA 90 which requires an airless sprayer to supply paint to the gun.
Ransburg is the only manufacturer in the world that produces both corded 240v and air driven turbine electrostatic spray guns. Ransburg also use DeVilbiss technology in nozzle/air cap production, DeVilbiss are regarded as the leaders in manufacturer of spray guns for atomised paint technology and they are the number one automotive spray gun manufacturer in the world.
Brands such as Graco with the ProXp electrostatic range of spray guns only produce air driven turbine models which require at least 17cfm of compressed air to make the turbine spin at the correct speed. These guns are not suitable for on site spraying applications unless you have adequate air supply to run the gun which most people don't.
Graco as they do with everything produce too many variants of the ProXp which confuses customers even more. In the Graco ProXp range of electrostatic spray guns they produce the following models just in low pressure versions –
Graco ProXp40 Low Pressure Electrostatic Spray Guns-
Part No. L40T10 - Standard Electrostatic Spray Gun
Part No. L40T16 - High Conductivity Electrostatic Spray Gun
Part No. L40T14 - Kv Booster Electrostatic Spray Gun
Part No. L40T15 - Kv Booster High Conductivity Electrostatic Spray Gun
Graco ProXp60 Low Pressure Electrostatic Spray Guns-
Part No. L60T10 - Standard Electrostatic Spray Gun 1.5mm
Part No. L60T11 - Standard Electrostatic Spray Gun Round Spray
Part No. L60T12 - Standard Electrostatic Spray Gun 1.2mm
Part No. L60T16 - High Conductivity Electrostatic Spray Gun
Part No. L60T17 - Waterborne Standard Electrostatic Spray Gun
(Graco also forgets to mention you need to spend another $20K on an isolation pump system for this gun to work)
Graco ProXp85 Low Pressure Electrostatic Spray Guns-
Part No. L85T10 - Standard Electrostatic Spray Gun 1.5mm
Part No. L85T16 - High Conductive Electrostatic Spray Gun 1.5mm
Part No. L85M10 - Smart Electrostatic Spray Gun 1.5mm
Part No. L85M16 - Smart High Conductive Electrostatic Spray Gun 1.5mm
If you needed a gun which one would you choose? Well to make it simple for you would just choose the L85T10 Standard 85Kv. This has a simple green light that indicates the gun is charging correctly and it produces the highest Kv out of the entire range. Most customers that buy the 40Kv because it's cheaper are disappointed with the performance of the gun, the 60Kv is much the same although it does have a bit more charge but it still lacks the power of the larger gun. The entire range of the Graco ProXp guns are really unnecessary other than the fact that they can fill an entire product brochure with dozens of guns to make the product look more comprehensive than it actually is.
Smart guns with the digital display don't do much for the average spray applicator, you can adjust the voltage but most people won't even bother. The Smart guns also have a self diagnostics tool which is not much help, if the gun does not produce any charge, it will either be the turbine is not spinning requiring a service or the module needs replacing because it's failed.
Ransburg simply produce two models of low pressure air turbine electrostatic spray guns, the Ransflex RFX 45Kv which is not sold in Australia due to zero demand and the Ransflex RFX 65Kv which reacts the same as the Graco ProXp 85Kv Standard. You can of course change nozzles sizes if you require more product flow and also fit round spray nozzles for special painting applications.
Wagner produce the GM5000 electrostatic spray gun which is 240v corded low pressure electrostatic spray gun. This gun has a power cord between the VM500 control box and the hand gun and it will require either a pressure pot or double diaphragm pump to feed the paint to the gun. This gun works exactly the same as the Ransburg Vector R90 but lacks the pedigree in terms nozzle and air cap manufacturing quality, as mentioned previously the Ransburg Vector R90 nozzles are made by DeVilbiss who are the world leaders in atomized fluid technology.
3) Spinning Bell Electrostatic Spray Guns
The Ransburg No.2 Deuce Electrostatic Process Hand gun is the only electrostatic spray gun with this technology. The No.2 guns don't actually spray paint in a conventional way, fluid is dispensed through a nozzle at the end of the gun into the spinning bell. The speed of the spinning bell combined with correctly thinned paint material actually flicks out of the bell as it spins, the electrostatic charge will cause the paint to wrap around the object being sprayed.
The Ransburg No.2 gun can coat pipes up to about 350mm in diameter from a single side, the charged paint will wrap completely and evenly around the pipe at about 99% transfer efficiency with next to nothing in overspray. These guns are very useful for spraying handrails, wrought iron gates & balustrades where application of spray is limited to one side.
The Ransburg No.2 Gun is a 240v corded electrostatic sprayer that has a voltage control box, 10m power cable and the hand gun. These units are mostly used with paint pressure pots that feed the paint to the gun, the pressure pot will require a small air compressor such as 2-3cfm as the air is only supplying the pressure pot, not the gun.
Ransburg No.2 electrostatic spray guns are widely used for on-site spray painting applications as they produce next to nothing in overspray and can achieve 100% wrap of the object being coated. The Ransburg No.2 does however require a certain skill level in use and careful mixing of the paint material but they are one of the most efficient electrostatic spraying system ever produced.
Round spray nozzles can be fitted onto low pressure electrostatic spray guns such as the Graco ProXp, Wagner GM5000 and even the Ransburg Vector R90 but these are just an emulation of what the Ransburg No.2 gun can do but they will all have some degree of overspray and no where near the amount of wrap.
AA Spray have been selling and servicing electrostatic spray equipment since 1993 and we are the largest Ransburg Electrostatic Spray Equipment dealer in Australia stocking all models and parts.
When you buy an electrostatic spray system from AA Spray we provide full training in the operation, use and maintenance to ensure that you can achieve the very best results.