The Sealey Guide to Spray Guns
Spray Guns fall into two groups:-
- High Volume Low Pressure (HVLP)
HVLP spray guns are generally used by professionals as they offer a superior method of spraying, allowing greater control.
They have a minimum of 70% paint transfer efficiency, with less bounce back. This helps to reduce paint costs, makes them more environmentally friendly and provides improved Health & Safety.
They require a low-pressure air supply but use high volumes of air. They are therefore, designed for use with compressors that are available with large capacity air tanks.
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Traditional Spray Guns
These are ideal for home users and by professionals for applying upholstery adhesives, primers and undercoats.
Most traditional guns use less air than HVLP versions and can be used in conjunction with smaller tank compressors.
Set-Up
The set-up on a spray gun is the diameter of the hole that the paint passes through in its nozzle. This figure is stamped into the nozzle. Paint manufacturers state on their instructions, the size of set-up needed to spray their paint. If this is different to the size fitted to your gun, alternative setups are available as optional accessories.
Gravity and Suction Feed
Paint is fed into the spray gun in one of two ways;
Gravity feed, where a paint is stored in a cup on top of the gun, using gravity to feed it into the gun.
Suction feed is where the paint cup sits under the gun and uses the air passing through the gun to draw up paint from the cup. Gravity fed guns are typically smaller and are designed for small jobs, such as touch up work.
CFM Rating
Spray guns and air tools have a CFM rating which stands for the amount of cubic feet of air required per minute to power them effectively.
Before making any purchase, check the CFM rating of your compressor, to determine which spray guns/tools are compatible with it. If you plan to use two tools at the same time, you will need to add their ratings together.
Types of paint
Modern automotive lacquers are spirit based, but base coat paints are water-based and are kinder to the environment. The latter can cause corrosion in spray guns unless they are designed for use with water-based products. All Sealey Spray Guns are suitable for use with water-based products.
Cleaning
Spray guns require a thorough cleaning after each use, to maintain their efficiency. This can be carried out by using manual cleaning tools. However, regular/professional users can use air operated gun cleaning tanks to speed up the process.
Hoses
Hoses are available in a variety of lengths and internal bores. The larger the bore, the greater the air delivery. This is particularly important when using tools requiring high volumes of air, such as spray equipment, sanders, polishers and large impact guns.
If your spray gun/air tool requires large volumes of air, use a shorter, big bore hose. The longer the distance from the compressor to the gun/tool the greater the loss of air pressure.
Hoses can be supplied loose, housed in a retractable hose reel or supplied coiled like a spring. Rubber hoses contain silicon which can contaminate your paint, leading to poor paint jobs. Always use a silicon-free hose, if you plan to spray paint.
Regulators, Moisture Filters and Oilers
Running a spray gun or tool on the wrong pressure can reduce its efficiency and lead to its premature failure.
Therefore, you will need to regulate the amount of pressure supplied to your spray gun/tool by using a regulator mounted on the compressor, or by using a wall mounted version.
Regulators can be supplied with a built-in filter to separate water from the air. This water occurs naturally in the compressor tank (known as condensate) and can ruin your paint job. It also causes corrosion in air tools. In-line water filters are also available that mount on the air inlet of a spray gun.
Oilers are designed to regularly supply oil to lubricate air tools. They must not be fitted when you plan to spray, as the oil will ruin the paint job.
They are available as an attachment to a regulator, or as an in-line attachment on the air hose.
View our current range of Spray Guns here: