How To Make A Foam Cannon


One of the top reasons a professional car wash is so effective is that they make use of industrial foam cannons. It’s not hard to see why they’re superior to hand washing your vehicle.

Something that makes the job of grit and grime removal easier just has to be worth a look. But we must take into consideration the expense.

A top of the range commercial foam cannon can stretch your budget to over the $200-$250 mark. Definitely a worthy expense if your washing 10 or more cars a day. But for us weekend detailers that price label is exorbitant. However, dont worry as we have the answer! 

How foam removes grime

Foam cannons make it easier for car soap to remove dirt by producing a thicker, richer lather. This dirt busting substance has superb grime busting qualities by use of surffactants which loosen the dirts grip on the surface.

While the sheer weight of the thick foam helps push the dirt down the panels.  This  is why washing with a foam cannon can be a great way to prevent any damage to your car’s paint by minimising human contact.

What we mean by preventing damage is that when washing your car you could be scratching the paintwork. As each time your wash mitt or sponge contacts the surface there is a chance that the grit and grime on there will get trapped on the mitt or sponge and dragged across the surface.

Effectively your mitt or spong become a sanding blosk, creating hairline scratches and those annoying swirls you see on so many cars thats just dull down the shine.

In this article, we’re going to explore how to make a foam cannon of your own so that you can enjoy the benefits of washing your car with this method and reduce the risk of creating thos shine businting scratches and swirls.

How To Make a Foam Cannon and se the foaming running off like this

What you need to make a foam cannon at home

There are many ways to make a foam cannon at home, with some methods being more complicated than others. Here, we’re going to focus on the simplest possible way you can use without spending too much money.

All you need to do is buy a regular garden pump sprayer. That’s the type that you’d use to spray chemicals on your lawn or water your plants.

These pumps come in many shapes and types, but you’ll get a better washing experience by using the kind with a hose and wand attached to it. Such as pictured below.

Once you have the garden pump sprayer ready, the only other thing you’ll need is a knife or screwdriver and regular car soap. Then, you can get started.

Converting a garden pump sprayer to a foam cannon

How do you convert regular soap to foam?

By ‘aerating’ or adding more air into the soap-water mix.

To achieve that with your garden pump sprayer, start by unscrewing the hose from the pump’s body. When you pull it out, you’ll see that there’s a part of the hose that runs all the way into the sprayer’s water tank. That internal part of the hose is where you’ll make modifications to turn it into a foam cannon.

But what exactly is the modification? You’ll be taking a knife or screwdriver to create a small hole in the pipe. Don’t make it too deep; it needs to be just about an inch away from the cap.

Remember: you’ll be making this hole on the part of the hose that runs into the interior of the pump, nowhere else. One small hole is all it takes.

Snow Foam Preparation

Now your ready to add the Snow Foam liquid. We suggest you dilute it with a 1:4 ratio. Thats one part snow foam to four parts water.

It can be mixed in a bucket and then added to the spray gun but we prefer to add the one part snow foam first then add the four parts water. We find it gives a better over all consistency this way.

Some typically good snow foams we suggest to try are Mother Triple Action Foam Wash and Meguiars Mega Wash. Both are specifically designed to produce heavy weight foam that will both work well with the spray gun and remove the grime.


When you fill the sprayer with car soap and water and then pressurize it, that small hole inside will allow much more air into the mixture. As a result, you’ll be able to get a much foamier spray of car soap all over your vehicle.

MOTHERS TRIPLE ACTION FOAM

MEGUIARS MEGA WASH FOAM

Advanced home-made foam cannon

As mentioned before, there are other, more sophisticated ways of making a foam cannon. There are alot more expensive ways to foam a car too! And to be honest all you need is the foam on in a realatively even coating, something that can be achieved quite easily.

But if you’re looking to build a more advanced version that you won’t have to operate by hand, you’ll need to add an electrical bicycle pump and bolt-in valve stem to your garden sprayer. This advanced version takes a bit more work, but the payoff is worth it. The electrical bicycle pump basically automates the entire process, so you don’t have to stop and pump the sprayer by hand every few minutes.

Position the car with ease of access all around to enable the electrical bicycle pump to be moved around with the sprayer and you will have the car foamed in no time.

NB: Please be aware of the dangers of electricity and water though. Ensure any plugs or extensions are concered and not exposed to water.

We will leave you with a check list of items needed.

How To Make a Foam Cannon Check List

  1. Garden Pump Spray
  2. One Gallon of good quality Foam Car Wash
  3. Good measuring jug
  4. Knife (Pointed end)
  5. Large Wash Bucket
  6. Water.