If you're planning to undercoat your truck this weekend, picking up a kellsport spray gun is probably the smartest move you can make. Let's be real for a second—crawling under a vehicle with a dozen rattle cans of undercoating is a recipe for a bad time, a sore finger, and a patchy job. If you want to actually get into the crevices where the salt and grime hide, you need a tool that can move some serious material.
I've spent plenty of time looking at different setups for rust prevention, and the stuff Kellsport puts out is usually the gold standard for DIYers and small shops alike. They aren't just generic paint guns; they're specifically designed to handle the thick, gooey stuff like Fluid Film or Woolwax. If you try to run that through a standard HVLP paint gun, you're going to have a frustrating afternoon of clogs and regret.
Why the Pressure Pot Design Matters
The first thing you'll notice about a kellsport spray gun is that it's usually a pressure pot setup. Now, if you're used to suction-feed guns (the ones where the cup sits on the bottom and "sucks" the fluid up), this is a whole different ballgame.
Suction guns struggle with thick liquids because they rely on the venturi effect. If the liquid is too viscous—like a heavy-duty lanolin-based wax—it just won't move. A pressure pot, however, actually forces compressed air into the canister, pushing the product up the tube and out the nozzle. This means you can spray in any orientation, even upside down, which is exactly what you're doing 90% of the time when you're under a chassis.
It makes the whole process faster. Instead of misting a light layer, you're actually applying a consistent, thick barrier. When you're trying to beat the winter salt, "thick" is exactly what you want.
Setting Up Your Air Compressor
One thing people often overlook is the air requirements. You don't need a massive, industrial-sized compressor to run a kellsport spray gun, but you can't really do it with those tiny pancake compressors meant for brad nailers either.
Usually, you want to be sitting somewhere around 60 to 90 PSI depending on the temperature and the specific product you're spraying. If it's a cold day, the wax is going to be thicker, and you'll need a bit more "oomph" to get it moving. I've found that if you can keep a steady 70 PSI at the gun, you're in the sweet spot.
Just a quick tip: if you're working in a cold garage, try leaving your Woolwax or Fluid Film buckets in a warm room overnight, or even sit them in a bucket of warm water for twenty minutes before you start. It makes the kellsport spray gun's job so much easier when the product is flowing like warm honey rather than cold peanut butter.
The Magic of the Extension Wands
The real reason people buy these kits isn't just the gun itself; it's the specialized wands that come with it. If you look at the frame of a modern pickup truck, it's full of holes, boxed sections, and tight spots above the fuel tank. You can't reach those with a standard spray tip.
A kellsport spray gun usually comes with a long, flexible 360-degree wand. You snake that thing into the frame rails, pull the trigger, and as you retract the wand, it coats the entire inside of the steel. It's satisfying to see the mist blowing out of the drain holes, knowing that you've reached the spots that usually rot out first.
Without these wands, you're basically just painting the outside of the frame, which is like putting a raincoat on but leaving your boots at home. The inside of the frame is where the real damage starts, and this gun is built specifically to address that.
Is It Going to Be a Mess?
Short answer: Yes. Long answer: Absolutely yes.
Whenever you're using a high-pressure tool like the kellsport spray gun to atomize oil or wax, you're creating a bit of a fog. It's not a "clean" job. You'll want to lay down some cardboard or a cheap tarp because whatever ends up on your driveway is going to stay there for a long time.
I'd also highly recommend wearing a Tyvek suit and a respirator. Getting lanolin-based wax out of your hair or off your skin is a process you don't want to experience more than once. But honestly, the mess is a small price to pay for a rust-free vehicle. The kellsport spray gun does a great job of directing the spray, but overspray is just part of the game.
Maintenance and Cleaning
One of the best things about using these guns with non-drying oils is that cleanup isn't as stressful as it is with paint. If you leave paint in a gun, it's ruined. If you leave Woolwax in your kellsport spray gun, it's not the end of the world because the product doesn't actually "dry" or harden.
That said, you shouldn't just toss it on the shelf and forget about it. Running a bit of mineral spirits through the gun after you're finished is a good habit. It clears out the nozzle and the internal pick-up tube so that next year, when the first snow is about to fall, you can just plug it in and go.
If you do find that a wand is clogged, usually a little bit of heat or a quick blast of compressed air from the opposite end clears it right out. These tools are built pretty ruggedly; they're mostly metal and feel substantial in your hand, not like the plastic toys you find at big-box stores.
Comparing to the Cheap Alternatives
I know what some of you are thinking. "Can't I just buy a $20 engine cleaning gun and do the same thing?" Well, you can try. I've tried. The problem is that those cheap guns are almost always suction-fed. They'll sputter, they'll clog, and they'll give you a very uneven coat.
When you invest in a kellsport spray gun, you're paying for the consistency. It's the difference between spending four hours fighting with your equipment and spending 45 minutes actually protecting your truck. If you value your time (and your sanity), the dedicated pressure gun is the way to go.
Plus, the build quality on these things is actually meant for repeated use. The seals are designed to handle the chemicals in the oils, and the triggers don't feel like they're going to snap off after the first gallon of product.
Wrapping Things Up
At the end of the day, rust is the silent killer of any good vehicle. You can have a perfect engine and a spotless interior, but if your frame turns into Swiss cheese, the car is junk. Using a kellsport spray gun gives you the professional-level capability to stop that from happening.
It's one of those tools that feels like an investment. Once you have it, you'll probably find yourself offering to undercoat your neighbor's car or your kid's first beater truck. It makes the job so much more manageable that you actually don't mind doing it once a year.
So, if you're tired of seeing those orange flakes of doom on your wheel wells, grab a kit, get a couple of gallons of wax, and let the kellsport spray gun do the heavy lifting. Your frame will thank you five years from now when everything else on the road is heading to the scrapyard and your truck is still solid as a rock.