Spray Guns – Gravity vs Siphon vs Pressure Spray Guns


– All right, we’re gonna go over the three kinds of spray guns that you primarily use when it’s comes to using an air spray gun. The typical options you’ll
consider are pressure feed, gravity feed and siphon feed. The material we’re using is about the same thickness as a Latex paint. And for the gravity and siphon feed, we had to thin it about 25% to get to the spray pattern you’ll see in this demonstration. We’ll go over each system, and look at the benefits and drawbacks, so you can make a wise decision about which might be right for you. First system is a pressure fed system. You have to have someway to
feed your material to the gun from a pressure pot or a pressure cup, They do come in smaller
cups that are two quarts and this is one of the primary
ways that you will paint. The major benefit to this, you have independent control
of air and fluid pressure. It will atomize heavier coatings, as well as deliver heavier
coatings to the spray gun. So if you’re using industrial paints, zinc’s, epoxy paints, things
that are highly viscous. Pressure pots often are
very good choice to go with and you can feed these
from with inside the pot from a single cork can or
however you like to do it if you wanna keep waste down and they will give you
a lot of versatility. They are the most versatile
of the three systems. The other main benefits of this system are they, it’s a faster way to spray compared to gravity and siphon feed. You can move a lot more
material through the gun as we can increase pressure to change how much paint we’re spraying. Grabbing the siphon will require you to
change the fluid nozzle to a larger nozzle. And that’s the only way you have really to control fluid flow. Having independent
control of fluid and air let’s me dial in how I’m
spraying (spray sound). You could see it will let
you paint pretty quickly and because I have independent
control of air and fluid you can control the break-up very well. And determine how much
paint to air you want, giving you a lot of versatility. One of the main drawbacks is, you do have a little more
clean-up required for this as you do have to flush
the system when you’re done with an appropriate cleaner up to the gun and the pot itself. So you will use a little more thinner, there are liners that are
throw-away for these systems. They’ll allow you to have a
little bit easier clean-up. And that is how the system works. We’ll show one more
time. (spraying sound). So you can see I’m moving pretty quick. I’m able to cover majority of
this section of the cardboard quick in a short amount of time. So next we’re gonna cover
siphon fed spray guns. The way these guns work,
air’s drawn across the top and the material delivering
it through the nozzle and that towards your product
where air is introduced here into the paint and it is atomized. Main benefits to these, they are very user friendly. There’s not a lot of
setting you can adjust. Since you decide the size of the nozzle determine how much
material you are delivering and that will control if
you’re able to spray the paint. Downsides to these, they won’t work well
with thicker paints often because you won’t be able
to effectively draw material through the nozzle. Additionally, they
aren’t available on HVLP. HVLP spray guns save
you a lot of paint waste compared to a conventional gun which is what these will be. The gun is simple to use. Clean-up’s easy because the cup’s smaller and some guys prefer the feel of it with the cup being underneath compared the cup above like a gravity gun. We’ll show you, it’s a lot
slower than a pressure feed. And it’s usually a lot slower
than a gravity feed as well which is one of the drawbacks
to these types of guns. They’re well suited for woodworking, thinner coatings,
stains, automotive paints and those sort of applications. We’ll show you how it works here. (spraying sound) So if you can see, they
are very easy to dial in centrally if you’re getting
material out the nozzle you will have it to be atomized because the air that’s
pulling that material up is the same air that will break it apart and it self regulates for
the most part air to paint so that you get a good break-up. The final type of spray gun that we’ll go over for air spray is a gravity feed spray gun. The benefit of gravity feed is that it allows you very good control over your painting because you can feather your needle in and out of your spray gun to allow for a little bit more control when compared to siphon. Pressure feed gives you a similar level of control as gravity feed but will feed a heavier and
thicker paints more effectively. Gravity feed is commonly used for wood stains and automotive finishing as two the most typical uses for it. Similar to siphon feed, you are limited in how much paint you can deliver at a time. Cause the way it works is
gravity will pull the material through the nozzle so you’re nozzle size is your primary way to determine if a paint will be able
to flow through the gun and how much paint’s being
delivered at a given time. For this particular paint, we had to thin it about 30% both for the gravity and siphon feed. With the pressure feed we are able to spray this
paint without any thinner. A benefit of gravity over siphon feed, they are available on HVLP or conventional or LVMP which allows you versatility when it comes to spraying
a paint efficiently and reducing waste. You’ll see it’s faster than siphon feed. We’ll show you that here. And you’re still getting good atomization. (spraying sound) So it’s a little quicker. Not as fast as pressure feed potentially. It’s very good for touch up work you don’t have the clean-up associated with the pressure pot. And it can be used also
in industrial paints if you’re using a smaller
product that you’re painting or just an occasional paint job and the paint’s not extremely thick. So that’s gravity feed.

14 comments

  • canada painter

    QUESTION; 3:33   do you think if the suction tube in the tank is longer then it needs more pressure to suck the paint up?

    Reply
  • Kun Huang

    Very useful information. Thanks for sharing

    Reply
  • Artie6937

    How about a video on tip, needle sizes

    Reply
  • Pittsburgh Spray Equipment Co

    The siphon spray gun can put out more material than shown the tip used in this video is a 1.8 which is a bit small when it comes to siphoning mateiral. As paint gets highly viscous like above a latex consistency you typically have to thin a bit more to get a good amount of material or use a larger tip.

    Reply
  • Heriberto Gonzalez

    Whats the diffrence between airbrush and spray gun if you don't mind

    Reply
  • AFFLICTION08011

    can u use siphon with the paint pot? if you unscrew the pot and connect hoses

    Reply
  • proverbs2life

    What would be considered "Airless"?

    Reply
  • Remington Alexander

    Thanks for the demo. I just had a 700 square foot wooden deck installed on the back of my house. In about a month it will be time for water seal. Which of the three spray gun methods do you recommend for water seal/staining a deck? Thanks for your time

    Reply
  • zetis

    This is The Best video on various types of spray guns. Thank you.

    Reply
  • Jānis Miška

    We could appreciate videos being more detailed, longer to have more of your experience, knowledge! Usualy painting videos (or other ) are more like to be just to show everybody your cool new equipment and stylish pants, not this useful info for knowledge – seekers 🙂

    Reply
  • salman khan

    ?

    Reply
  • Keefe Borden

    Thanks for the video.

    Reply
  • Andrei Fasola

    I wanna buy gravity for my car but I wanna make sure I can spray latex. What's the issue with diluting latex paint – I don't get it? You say the atomization is good, so why not spray latex with gravity, it's faster, more control …

    Reply
  • travis

    Good video, clear explanation! Thank you.

    Reply

Leave a Reply

Your email address will not be published. Required fields are marked *