Spraying for Time.
Ah, this blog post is well overdue and I want to cover a subject that I get asked about regularly. I’m going to go into a lot of detail here so you might want to get yourself a coffee and get comfortable because we’re going to be talking about spray painting your projects. I know there’s a lot of information on the internet regarding spraying, but not so much when it comes to the different types of paint, such as Annie Sloan Chalk Paint vs latex paints and primers. Furniture paint is very different to the type of paint that would usually be sprayed, for example something like car paint, but in this article I’m only going to be talking about painting cupboards for Shabby Chic projects So what should you be looking for when you are thinking about spraying furniture? Let’s look at the first few things to consider.
What Type Of Spray Gun Should I buy?
For this purpose, there are only really two types of spray equipment that we need to discuss, HVLP (High Volume Low Pressure) and airless. HVLP are basically regular spray guns that you would use with an air compressor in order to atomise the paint and spray it onto your project. 99% of all car body shops will use this type of spray equipment as well as some pro furniture finishers. Let’s talk about HVLP first.
As we’ve said, HVLP is just a regular air driven spray gun that is designed to work on a low air pressure of around 2-3 bar and deliver an atomised spray pattern with a high transfer efficiency and minimal overspray. Say what? That’s just a fancy way of saying that more paint ends up on the piece you’re painting and not as a mist in the air, thus saving paint and being more efficient.
Sounds perfect right? Well there are a lot of other factors to take into account here. A HVLP gun needs a compressor or a turbine to drive it. This is an expense to be considered as if you plan to use your gun a lot, especially with high viscosity paints (thicker) you will need something that delivers a lot of air at a constant pressure. The way that air delivery is measured is via CFM (Cubic Feet Per Minute) or better still FAD (Free Air Delivery) The higher the number of these values the more air your compressor can deliver without running out of puff every few minutes. If you are spraying low viscosity paints (thinner) they will flow much easier and the compressor will not have to work so hard as you will be able to paint in quick passes with good paint flow. If the paint is thicker, less will come out of the spray gun at once and you will have to move the gun much more slowly, and thus need more air!
Here’s where it gets challenging, in order to get a more stable flow of paint there are essentially two things you can do, you can buy a spray gun with a larger diameter needle of you can thin down the paint to lower the viscosity. The needle of a HVLP spray gun is just that, it’s a long thin bar with one needle sharp end that runs through the body of the spray gun that retracts when you pull the trigger and allows paint to pass where it is atomised by the air and comes out as a spray mist. The larger the needle, the more paint it allows to pass. Most high build paints such as primers would be sprayed with something like a 2mm needle size.
The downside to this is that even at 2mm, a paint that is slightly too thick will struggle unless it has a very good compressor driving it. I have a 3HP 150 litre compressor with a CFM of around 11 and my 2mm tip HVLP gun will still clog and spit regularly if I mix the paint just a little too thick or get a piece of goo from the edge of the can mixed in with the paint. If a blockage does occur, I have to strip the tip of the gun down and remove the blockage before I can carry on spraying.
So why not just make the paint real thin and then it will be easy to spray, right? well..er..no, well sometimes but it depends on the paint. Most paints are designed to be thinned to a maximum of around 10% before their integrity is adversely affected. If you thin the paint too much you generally lose the covering power that you need and invite runs in the paint because it’s just too thin to stick. Plus the whole point of spraying is to save time, so if you have to apply lots of coats, what’s the point? In order to do a good job we need the paint to be applied without it being too thin to give good coverage and needing multiple coats.
This is generally the part when people leave me comments to say “hey..I have been using HVLP for cupboards for years and I’ve never had these problems”. All I can say is that everything written here is based on my experience and I have spent many, many hours (and a ton of money) trying to find the best solution for spraying and this is just me sharing my experiences. I welcome any comments with additional tips or advice on the subject.
So what about airless? If you have a store bought piece of furniture with a lovely smooth paint job, chances are it was painted with an airless spray rig. Airless is what most pro painters and decorators will use when they are looking to lay down a lot of paint in a short space of time. Airless works differently from an HVLP set up in as much as it literally ‘pushes’ the paint out through a nozzle with a powerful piston pump that can generate enough force to tear your skin should you be unfortunate enough to get your hand in the way of the paint stream, so great care must be taken when using these. Airless will spray thicker paints much more easily than an HVLP sprayer without the need to thin down the paint. So is there a downside?
Of course there is:) Airless sprayers tend to be expensive and cheap ones don’t usually live long lives. They are pump driven, so the pump needs to be primed (or filled) with paint. On a full sized rig this can use a lot of paint. Then you have to keep the paint trough filled so that it doesn’t run dry. So if you’re looking to use a small can of paint and just spray a few items, the priming and the clean up of a full sized rig might not be at all worthwhile after all. What did we say about saving time!
So what’s the answer? To be honest there is no perfect answer, spraying can be a complete hassle, but then anyone who has painted a dining room chair set will also know what a hassle a brush is too! So here’s the best solution I have found that ticks all the boxes that it’s possible to tick for me. If I want to spray something I use a Graco Truecoat Pro II cordless spray gun. It is essentially a compact cordless airless sprayer designed for smaller paint jobs for pro painters.
Now I want to be clear. I’m in no way being helped by or affiliated to Graco when I write this, I bought my spray gun at full price from a guy that imports them from the USA and it wasn’t cheap! There are cheaper ones out there, much cheaper but Graco make Pro equipment, this is not DIY shed quality.
The thing is it can be loaded with just about any kind of paint, including Annie Sloan Chalk Paint without it being thinned down and still spray it to a very high standard. It will take a quart of paint at a time so I don’t have to waste a lot of paint in priming the pump and it’s manoeuvrable enough to use around cupboards. So is it perfect? well no, don’t get me wrong, I love it but it was £600 when I bought it (a lot for me to spend on a sprayer) and boy does it get through paint quickly. That said, it will cover in one coat. As I like to say, one and done! That’s what this spray gun does and it does it well.
Also if there is a paint clog, the tip can be reversed and ‘backwashed’ to remove the blockage
The bottom line is, what price do you put on your time? If you said £10 per hour and you could paint a cupboard in two minutes instead of two hours, Then you’ve saved nearly £20 0f labour. The equipment has paid for itself by the time you have painted 30 pieces. It’s a crude example but you take my meaning.
Take a look at the videos below, I managed to paint an entire cabinet in Wickes Chalky Flat Matt paint, straight from the can in 1 minute and 54 seconds!
So there you have it, we’ve looked at the ways that you can spray paints such as the Annie Sloan Chalk Paint and the various options and pitfalls that you may face depending on what method you choose.
I know I said that I would talk about the various types of paint that these sprayers will spray, Latex, Annie Sloan Chalk Paint etc but to be honest I kind of use the Annie Sloan Chalk Paint as a bit of a bench mark for this example because it’s far thicker that most latex paints I’ve ever used, so if a spray gun will handle Annie Sloan Chalk Paint without it being thinned then it will handle all but the thickest of paints out there in the market place.
So Is spraying a time saver? Well it certainly can be if you have the right space for it and can line up a few cupboards to paint at the same time, otherwise you may just find yourself washing out the spray gun over and over and wasting your time in a different way!
I sincerely hope that this article has been of some help to some of you to make an informed decision on what equipment is right for you.
Please feel free to comment or ask any questions below. Happy Spraying!
UPDATE> Congratulations to Sian Roberts for guessing that the blue cupboard took 1 minute and 55 seconds to paint. I actually had it at 1 minute 54 but you are definitely the closest guess, so you win a prize! Well done!