Time and time again, we've waxed lyrical that snow foam is our favourite part of the car cleaning routine. Aside from being the most visually exciting step of any cleaning process, it also has the vital duty of helping soften the most stubborn muck.
The effectiveness of snow foam depends on a lot of variables, and your technique can make the difference between perfectly preparing paintwork on an excellent bout of shampooing or wasting your time. Choosing the best snow foam is the first step, but it also makes sense to know how to use it best.
With our extensive snow foam testing under our belts here at CAR, we've come up with some of the tips we've learned to get the most from the product. We also spoke with Marloes Rots from Autoglym to give us more tips to ensure you get the best results possible from your snow foam.
CAR's five tips to get the most from your snow foam
Snow foam from the bottom up
When applying the snow foam, work from the bottom to the top of the vehicle, making sure to include the glass and wheels. Marloes says "the wheels and bottom of the car are usually the dirtiest areas and so need a longer dwell time to remove all dirt."
The most effective snow foams won't be shaving foam thick, they'll dribble down the body of the car pulling grime as they do. In practice this means the lower parts of the car will get the most dwell time with the snow foam and the snow foam will have the best chance to lift dirt.
Combine snow foam and prewash for the best results
The hidden weapon in the fight against dirt, a citrus prewash layered underneath a snow foam, will deliver a much better job than snow foam alone. Prewashes often use citrus oils, an excellent degreaser that effectively cuts through grime. The downside is that these chemicals typically won't dwell as much as snow foam.
The best solution is to combine both products and create the ultimate pre-cleaning cocktail. First, apply a layer of prewash and quickly cover it with a layer of snow foam. The snow foam will dramatically increase the dwell time of the prewash and allow it to easily cut through the dirt.
As snow foam is the gentlest of all the pre-cleaners, it struggles against filthy cars, this technique will cut through that grime with ease.
Watch your dwell time
Most manufacturers will print a recommended dwell time on the bottle, usually between three and 10 minutes. Marloes recommends that you leave "the pre-wash foam to dwell and loosen dirt for up to 10 minutes but ensure it does not dry as this can leave streaks. Remember that drying times might differ according to the ambient temperature, the temperature of the vehicle’s surfaces and whether the vehicle is in direct sunlight."
As the product evaporates in the sun, you risk the product drying on the paint and leaving those dreaded streaks. For this reason, it also makes sense to check your bodywork is cool and ideally out of the sun before you begin.
Start rinsing from the bottom and work your way up. This will ensure that the snow foam applied to the upper portions can continue to dwell without it diluting, making it easier to see any missed spots during the rinsing process.
You don't need a pressure washer
It's natural to assume you need a powerful pressure washer with a massive flow rate and pressure that could strip the paint off a car. In reality, any pressure washer with a decent foam cannon should be able to get a consistent layer of snow foam, but did you know that they're not necessary?
Foam sprayers are a fantastic handheld alternative, using hand-pumped pressure to apply the foam. The benefit of using a foam sprayer is that you depend on power cables and a water source. It also gives you far better control, allowing for a targeted approach.
Remember you'll need to rinse the snow foam, and a foam sprayer won't cut it to get the snow foam off. At the very least, you'll need to team a foam sprayer with a hose if you want to skip the pressure washer.
Be careful where you point your cannon
It's a simple but crucial step you'll kick yourself for forgetting to do. Marloes recommends that prior to snow foaming you "do a quick test burst of the foam gun with it pointing away from the vehicle," adding that it can fly off if not properly secured, potentially damaging your paint.
Most quality units will click into place with a reassuring noise, but don't take it for granted. For the ultimate peace of mind, point your cannon at the ground for the first squeeze of the trigger. You can now apply your foam if it doesn't shoot off.
Meet the experts
Marloes Rots is a Marketing Manager for Autoglym. Since 1965 Autoglym has been producing car care products and remains a top seller in the UK. It currently offers a snow foam, called Polar Blast, as well as a foaming cannon as part of its range of products.
Ryan Gilmore is the Deputy Autos and Tools Editor for CAR, specialising in car cleaning and hand tools. With an MA in Automotive Journalism, when he's not testing buckets he can be found looking at old Porsches.