Airless Spray

A Basic Guide to Airless Spraying Equipment

An Airless sprayer PUMPS paint from a container and pushes it out under pressure through a spray gun.
 

Airless spraying is fast and efficient and if done properly can be very clean.

 
Mostly used with emulsions and masonry paint but airless can also be used effectively to spray acrylics, solvent paints and preservatives.

Machine Suitability

Not all paints are the same thickness (viscosity), more powerful machines are needed to pump the thicker products to the gun. This is why we have a rating on machines expressed as the max tip size, I.e. Max Tip size 19thou (thousandths of an inch)

 
The tip is the part that goes into the gun and comes with different size holes (orifices) for the paint to escape. Thicker products need a larger orifice than thinner products, to support the amount of paint needed at the tip, the machines need to be able to keep up.

In simple terms a more powerful machine is required for thicker paints.

 
Both Tip sizes and machine capability are expressed in thousands of an inch (thou). Typically, emulsion needs a 15 to 17 thou tip & a machine that will support a tip of this size. Masonry paint need a 17 to 19 thou tip & a machine that will support a tip of this size.

You can buy different tips for the different products and with different fan widths.   You will need to make sure you do not buy a tip that exceeds the output of your machine.

All machines from all brands use this exact same system so you can very soon identify its suitability.

 
As regards durability, if you are planning on using your machine daily or on a regular basis then you should buy a machine with greater requirement so it is not working at the maximum output all the time.

If you are planning on using the machine on a building site you will need a 110v machine in the UK.

The Gun

The Purpose of The Filters

Tips explained in Brief

Tips come with two measurements. Width & Orifice (size of the hole). The most common tip is a 515, more information is shown below in the help pages but in brief the first 5 means it is 50 degree fan which equals a 5 inch radius. If you can remember your school maths lesson you can quickly work out is is a 10" Diameter Fan (Twice the radius). A 615 would therefore be a 12" fan and a 415 a 8" fan.

The second two numbers are the orifice size, the bigger the hole the more paint that comes out, the smaller the hole the more paint is restricted.

This makes it easy to add control to your spraying and to find the tip best suited to the product. Imagine spraying blockwork with a tiny 9 thou tip when you want volume coming through or you are varnishing your furniture with a massive 21 thou tip allowing no time to work.

The right tip means a better job!

What Can I Spray?

Most paint products can be sprayed, however the equipment needs to suit the material to be effective. For instance you could spray masonry paint with an HVLP system but you would have to thin it down so much it is not practical. If you are unsure you should call us. This list covers most basic products and I have included the best tip option where appropriate.

What's the Difference Between Airless & HVLP

Airless sprayers PUMP paint from the can at pressure to the gun. The paint is then pushed at high pressure through a small tip to create a fan pattern that hits the surface. This method is very fast and means a great deal of paint can be applied quickly even over textured surfaces. An Ideal use for an airless system is new work or masonry on houses.

HVLP machines use air at low pressure to carry paint to a surface. They are ideal for trim finishes, lacquering etc. after using an HVLP to paint radiators you will not want to go back to the brush & fitch!

There are loads of different machines...HELP!

For most decorators, a machine that sprays emulsions, smooth masonry and acrylics is adequate. It is when you start spraying more often you will find a larger unit will cope more easily with your demands.

Airless machines are 'rated' by the max tip size they will cope with. The LP400 is a 21 thou machine which means any product that will spray using a 21 thou tip (or below) will go through. If you have a product requiring a 27thou tip an LP400 will not be strong enough to pump such a 'thick' liquid.

I can find Machines cheaper in the USA or on Ebay!

This is true, we sell on Ebay sometimes but they are the same machines at the same prices. There are people selling on Ebay who have bought machines from the USA directly and put them up for sale...BEWARE! these machines are not CE marked, carry the wrong plug (or have been changed at home) and will void your insurance if problems arise. The top brands are keen to see an end to these 'black' imports.

Why buy from MP Tools?

We have supplied and hired spray equipment for 6 years in the Hampshire / Surrey area. Our online sales does not mean we cannot offer our expertise to new sprayers or old hands. We carry machines in stock along with accessories, parts and consumables.

You can feel assured that when we have taken your payment we will not be hiding away from our responsibilities. A happy sprayer will return for more tips & filters and we need to keep customers coming back. Other sellers may import non CE machines from the US, we do not, all our machines are CE marked and are fully guaranteed.

More detailed Tip Information

 
The relationship of the tip opening (orifice) to spray pattern size is:

The larger the orifice is, the more paint that will flow through...

Given a constant orifice size, an increasing fan width will apply a thinner coating of material to the surface because a given amount of material is distributed over a larger area.

           

Recognising the number on the tip and what they mean
 manufacturers typically use three numbers to designate tip size, for example you could have a 517 or 211.

The first digit refers to the fan radius and is one-half the size of the working fan width. The second and third digits refer to orifice size in thousandths of an inch; thus, the 17 in 517 refers to an orifice size of .017 inches.

Which tip size to buy? Well now you know what the sizes mean, the question is which sized do you need? This will depend on:

• A: Area you are spraying.
  Example: If you were spraying a 4 inch baseboard in a new house, you would not pick out a 517 (10 inch fan) to spray it with.
  
• B: What size sprayer you have
  If your pump is rated at a max tip of .017 you can not spray with a 519 tip
  
• C: Kind of material you are spraying ( Example latex primer, or oil base stain. )
  This is actually not as important of a factor as you would think, since a 415 would spray either of the above mentioned materials, but is a factor to consider.

We made a TOP Seven “most popular” sizes we sell and their main usage. Top Seven airless tip sizes:

• 415 Would be the most popular size for spraying just about anything. Walls, doors, ceilings, decks, exterior walls,  a good all around tip.
  
• 517 Very popular for spraying int. walls, and int. ceilings. Good on blockwork.
  
• 413 This is good size for more controlled output (smaller orifice) on wall areas.
  
• 209 For thinner products with a controlledfan. Alkyds, Acrylic Eggshell etc.
  
• 515 About the same areas as a 415, just a bit wider fan width.
  
• 211 This is a very small tip for emulsion, great for cutting in or when control is essential.
  

• 519 Ideal for masonry paint, allows a large amount of a thicker product through and gives a 10" fan.
  
  
  Tip Chart - Selecting the right tip for the task...
  
  
  
  
  

• Understanding Airless Filters a little more..
  

• Airless filters cost very little but make all the difference when using a gun. Their purpose is to stop dirt in the paint getting to the tip and blocking it, so it is important that when using a small tip you use an even smaller gauge filter to catch the bits. Also if the filter is blocked up you need extra pressure to force paint through putting excess strain on the machine and a frustrated user.
  
  Pencil filters are colour coded as follows :-
  
  Red       Very Fine               Varnishes, Woodstains etc.
  Yellow    Fine                       Undercoat, Gloss, Acrylics etc.
  White     Medium                 Emulsions
  Green    Course                   Masonry paints
  
  Most machines have a second or even third level of filtration so that the paint at the tip is as pure as it can be.
  
  

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