Undercoating

[T5 copper]

What is the best undercoating product.

 

[Timmayy]

I like the POR15 and truck bedliner over it. There are also a couple of imitators that I've used also to the same affect. My buddy swears by the thick Rustoleum that he brushes on everything.

 

[493 Mike]

I used epoxy primer on bare steel with Raptor tintable bedliner. Easy to spray and achieve the texture you want. I tinted mine gray to go with my exterior paint and interior.
Mike

 

[R413]

Best for what? Protection or looking factory?

and truck bedliner doesn’t belong on a classic car.
I walk away when I see a car for sale with that stuff on it.

 

[493 Mike]

Best for what? Protection or looking factory?

and truck bedliner doesn’t belong on a classic car.
I walk away when I see a car for sale with that stuff on it.

Not everyone "restores" these cars.
Mike

 

[slimt]

I use nothing that traps moisture .

 

[Biopack]

HUD 12. This works really well.

 

[Builderguy]

This what my factory undercoating on the RR looked like after 48 years. Here in Michigan, if it wasn't undercoated, the road salt would have eliminated most of the underside metal. This was a daily driver back in the day, nothing special at the time. Driven hard and put away wet 12 months a year. Only one small rust hole near the gas pedal (probably from the carpet being soaked with salt water for 4 months out the year).

And this is what it looks like after a new application. It was a three part mix and then kevlar addition (for texture). Once dry it look like the factory job. I left some in the hopper and after it dried I pulled it out a hopper decoy!

 

[zyzzyx]

If you want to protect and stop rust, a good industrial cosmoline will work great but will not
look factory. Bed liner looks great but any moisture that gets between the frame rails and
pinch welds will be trapped and rust away at the spot welds. Think about what you will have
to go through later if you want to remove it! Rick's Resto has some authentic undercoaing
available for a decent price! I used it on the inside of my quarters.

 

[70ChargerRT]

Ah buddy lol. It’s according to what your plans on. Full blown Resto show car or are you going to drive the damn thing a lot? Show car quality I’d use something like Resto Rick, he makes a good product but besides that I absolutely hate that rubberized coating. I wont put it on a damn thing I have, it shouldn’t even be put on a car besides a nut and bolt Resto. It’s nasty, gets dirty easy, hard to clean and it’s just cheap looking. Looks like something bondos lovers like to use. Just spray the **** heavy until it hides everything lol. If you’re going to use anything I’d use a spray on bedliner. Like raptor liner if you want to tint it. It shows every detail and it’s hard to hide any half *** metal work with it. I like a more textured bed liner like Herculiner under my vehicles. The **** last, keeps moisture out, easy to clean and looks great.

 

[hunt2elk]

I like the stuff Rest Rick makes as well. Spray it on in multiple coats with a Shutz gun.

 

[gkent]

Bed liner looks great but any moisture that gets between the frame rails and
pinch welds will be trapped and rust away at the spot welds.

No matter what you do, rust can rear its ugly head in one form or another. I'm facing the "undercoating" dilemma right now. What to use and where to use it. The car was dipped and there is some rust seepage at the seams - this despite ZERO moisture on or near the car and despite being epoxy primed - twice! I don't want to spray anything in the frame, etc. before paint or bedliner in case it causes adhesion problems but I think right after painting I'll spray rust converter into all those areas, let it dry for a couple weeks then spray in Rustcheck or similar product.

 

[zyzzyx]

I had my GTX bottom blasted and did two things to make my brain not hurt! It was on a rotisserie,
so I mixed up some Epoxy primer and thinned it down with Acetone. I shot all of the areas where
the rails are spot welded to the floor pans with high air pressure and a narrow spray pattern. I then
sprayed the whole bottom with Epoxy primer, then paint. After paint, I thinned down some good
cosmoline and applied it to all of the rail to pan areas and let osmosis pull the stuff in to protect
the pinch welds. Done! Too much B.S., but hey, It's mine. Didn't cost me anything but the bill from
the Psychiatrist!

 

[TrackPack]

Paint. If it's good enough for the top, it's good enough for the bottom.

 

[493 Mike]

We will all be dead before rust eats these cars!
Mike

 

[zyzzyx]

Thanks for reminding me!

 

[dadsbee]

Paint. If it's good enough for the top, it's good enough for the bottom.

Yep !