Fluid Film coating: how to spray?

[JTK]

If you're going to use aerosol cans for cavities, I'd get a hose adapter for the can if applicable. A few of my vehicles have the little red plastic straw injected into rockers or door cavities because it popped off the can and shot in there.

Any of the oil, wax or lanolin based products need to be re-applied every so often and it's best to do it when it's going to be warm and dry out for a few weeks. None of them are once and done, aside from Noxudal, but I have my doubts that even Noxuldal is for salt belt climates, without periodic touch ups, etc.. I've been doing FF and WW myself for about 6yrs now. I currently have a 5gal pail of WW and about 8 cans left of a 12pack of aerosol FF cans. I like the cans for general use and quick touch ups.

 

[Donald]

I vote Noxudol as it comes in an aerosol can and you can attach a "wand" thingy to help get it into cavities. Noxudol is a waxy rust preventative that will actively fight rust and convert it to an inert material. Noxudol 700 goes in cavities as it is a bit thinner and Noxudol 300 is the undercoating. Dries to a hard waxy coating, not a sticky goopy mess.

They both go on thin and tend to wick into tight nooks and crannies, then dry hard over a week or so.

But if you have started with another more oil based product you probably have to stick with that or a similar product.

Does Noxudol "creep" ? The oil based products like CarWell or NH Coatings creep over time. So a scratch or missed spot will likely get taken care of.

 

[Rand]

On used vehicles that have seen salt.. I'd go with the GOOP vs a wax IMO.

Noxudol has some good products.
but I'd go blaster shield, FF, woolwax, Krown etc.

Krown has been amazing on the 2020 ram.. no rust. A few pieces of rubber weatherstripping were swelled.. now after spraying they are all wiped off with a rag.
Yes it can be a dirty mess. working under it.. but I'd take it over the alternative.
The 2013 equinox was rusty-er after 1 winter than the ram after 6 winters

 

[Donald]

On used vehicles that have seen salt.. I'd go with the GOOP vs a wax IMO.

Noxudol has some good products.
but I'd go blaster shield, FF, woolwax, Krown etc.

Krown has been amazing on the 2020 ram.. no rust. A few pieces of rubber weatherstripping were swelled.. now after spraying they are all wiped off with a rag.
Yes it can be a dirty mess. working under it.. but I'd take it over the alternative.
The 2013 equinox was rusty-er after 1 winter than the ram after 6 winters

There is a vacuum hose that engages the front axle of the 4X4 drive on my F250. Rust prevention products swelled or did something such that the front axle would not engage. A quick and low cost fix was to replace the vacuum hose. Something to keep in mind.

 

[Lubener]

You can spray it like you mention, or you could even use a paint brush and brush it on

Brush it on?? That would take forever.

 

[Kestas]

Brushing wouldn't force the material into all the nooks and crannies where corrosion typically starts. Spraying does a better job.

 

[The_Jeff]

Brushing wouldn't force the material into all the nooks and crannies where corrosion typically starts. Spraying does a better job.

Yeah you REALLY want to get it in holes in lower control arms and subframes.

 

[Rebound]

these are all great suggestions on how to do it the best way. If you're lazy like me you just put each end of the car up on ramps and spray about 3 cans of FF on everything underneath that looks like it could rust, avoiding rubber components (per FF directions).

Yeah, but here’s the problem: If you look at cars with rust, there’s a lot of rust on quarter panels and doors. It’s very common, so just spraying underneath the car is not enough.

Undercoating is like house painting: Prep is everything. The actual spraying is easy. First you have to remove ALL underbody panels and wheel liners, clean underneath if the car’s been in salt, and then spray not just inside the frame and beneath the car, but also inside all the quarter panels, door panels and engine compartment. This is why you want to avoid guys who charge $100 for an undercoat cause there’s no way they do all that. It’s also why I prefer DIY; I know it’s being done the right way.

 

[KrisZ]

Yeah, but here’s the problem: If you look at cars with rust, there’s a lot of rust on quarter panels and doors. It’s very common, so just spraying underneath the car is not enough.

Undercoating is like house painting: Prep is everything. The actual spraying is easy. First you have to remove ALL underbody panels and wheel liners, clean underneath if the car’s been in salt, and then spray not just inside the frame and beneath the car, but also inside all the quarter panels, door panels and engine compartment. This is why you want to avoid guys who charge $100 for an undercoat cause there’s no way they do all that. It’s also why I prefer DIY; I know it’s being done the right way.

More or less this. I would say when doing it for the first time, prep is the most important at that point. You want to expose as much of the metal as you can, so that it will get sprayed. After that, it's mostly the high wash and exposed areas that need to be refreshed. The covered areas will naturally retain the rustproofing coating for much longer than the exposed areas. You can hit them every second year.

And after few years of proper applications, the vehicle should have a thick enough rustproofing layer that annual applications shouldn't be needed.

 

[Rebound]

More or less this. I would say when doing it for the first time, prep is the most important at that point. You want to expose as much of the metal as you can, so that it will get sprayed. After that, it's mostly the high wash and exposed areas that need to be refreshed. The covered areas will naturally retain the rustproofing coating for much longer than the exposed areas. You can hit them every second year.

And after few years of proper applications, the vehicle should have a thick enough rustproofing layer that annual applications shouldn't be needed.

Totally agree. Inside the frame rails and door panels and quarter panels, the goop is undisturbed and will stay there for years.

 

[CleanSump]

Plastic painter's sheets at the home improvement store layed out on the driveway and then drive over them. Bricks, rock, or even wrenches or whatever may be needed to keep the wind from blowing them around.
This will save a huge mess on your driveway or garage floor.
Wear a spray painting mask. It may be a pain, but your health will thank you.