Bed Liner Undrcoat

[318 Six Pack]

I am in the early stages of shopping for a good bedliner material to use as an undercoating/rust resistant protector on my 1972 Charger. Desired features would be that it has that same look as old undercoating, or at least as close as possible. No sand/texturing stuff, or at least that can be an option for the user to mix in that I will opt out of.

Will be fixing all of my rust-through areas of course, but on areas without surface rust should those be stripped to bare metal too?

What about using a high-zinc etching primer before the undercoating?

I keep getting drawn to the Rust-Oleum products, but not sure if these days they prevent rust as well as their reputation.

Has anybody tried this and how well does it hold up over time?

Thanks in advance!

 

[krowbar]

I use 95% cold galvanize spray on clean metal. I even use phosphoric acid ( OSPHO) on rusty areas that I can't get at to sand to clean metal. I've used the bedliner in 1 gallon can and brushed it on the inside of my trunk. If the original paint stays on after I use a wire wheel, I leave it on. This is on areas you normally wouldn't see. If it's body panels, I would take it down to bare metal. But hey I'm not making a show car. The bedliner in a can is a little thicker than regular paint, but it's pretty tough.

 

[Propwash]

Personally I would sway away from the off the shelf stuff and use a professional line of product. SEM as well as a few others make a good line of 2K Epoxy based bedliners that you can buy in a kit. These are what a truck shop would use to give you that tough as nails coating. I have used the SEM Rock-it liner on a couple of my Mopars, my truck and sprayed in for several folks for some extra dime, and it's good stuff. It utilizes a catalyst hardener and is much more rugged. The kit comes with an applicator gun, bedliner, catalyst and a mixing cup. If you have a halfway decent sized compressor and can dial in a an air regulator, you'd have no problem spraying it.

http://www.tcpglobal.com/autobodydepot/sembedliner.aspx


It will take on a similar appearance to factory undercoating, but a little less texture. If you want to duplicate the factory undercoating, below is probably the best:

http://www.restorick.com/proddetail.asp?prod=Undercoat

Sprays on with a typical body schutz gun. 3M also makes a decent body schutz you could use. One thing to remember..typical any 2 part product out of a gun is going to be more durable than something out of a can.


As far as prep, IMO I would either use epoxy primer or a decent rust preventative coating/sealer, like Rust Bullet. Beforehand, I'd make sure you have nice clean shiny metal. Grind/sand off any rust and if you can't..do like krowbar mentioned, use Ospho to alleviate. Rust Bullet is a converter/encapsulator/sealer as well, but never the less, try to get as much rust as you possibly can gone before applying any type of coating. The only thing I would worry about with some etching primers is that they don't take too well to some of the overcoat's that go over them. I couldn't tell you how a bedliner/undercoating would react with your High-Zinc etching primer. I have sprayed over Zinc based weld thru primer without incident.


Hope it helps, good luck!

 

[kellycom]

i'm using the below in the trunk of my 66 Charger. I'm still in the process of re-doing the inside so i cant tell you how good it is. I bought it @ advanced auto parts. 2 cans for 12 bucks on sale. figured it would work pretty well in the trunk. It disnt go as far with the first can as I would have hoped. should take maybe 3-4 cans to get the coverage i am looking for in the trunk.

http://www.amazon.com/Dupli-Color-UC102-Professional-Rubberized-Eliminator/dp/B003OFCY9S

 

[Michael789]

I used rust bullet on the floor pans, roof and trunk after I removed all fine surface rust and paint , after that I used rust-oleum professional truck bed lining in a gallon can and I have to admit that stuff is solid as a rock.I am well pleased with the results.

 

[krowbar]

I used rust bullet on the floor pans, roof and trunk after I removed all fine surface rust and paint , after that I used rust-oleum professional truck bed lining in a gallon can and I have to admit that stuff is solid as a rock.I am well pleased with the results.

That's the kind I used. Rustoleum

 

[318 Six Pack]

Personally I would sway away from the off the shelf stuff and use a professional line of product. SEM as well as a few others make a good line of 2K Epoxy based bedliners that you can buy in a kit. These are what a truck shop would use to give you that tough as nails coating. I have used the SEM Rock-it liner on a couple of my Mopars, my truck and sprayed in for several folks for some extra dime, and it's good stuff. It utilizes a catalyst hardener and is much more rugged. The kit comes with an applicator gun, bedliner, catalyst and a mixing cup. If you have a halfway decent sized compressor and can dial in a an air regulator, you'd have no problem spraying it.

http://www.tcpglobal.com/autobodydepot/sembedliner.aspx


It will take on a similar appearance to factory undercoating, but a little less texture. If you want to duplicate the factory undercoating, below is probably the best:

http://www.restorick.com/proddetail.asp?prod=Undercoat

Sprays on with a typical body schutz gun. 3M also makes a decent body schutz you could use. One thing to remember..typical any 2 part product out of a gun is going to be more durable than something out of a can.


As far as prep, IMO I would either use epoxy primer or a decent rust preventative coating/sealer, like Rust Bullet. Beforehand, I'd make sure you have nice clean shiny metal. Grind/sand off any rust and if you can't..do like krowbar mentioned, use Ospho to alleviate. Rust Bullet is a converter/encapsulator/sealer as well, but never the less, try to get as much rust as you possibly can gone before applying any type of coating. The only thing I would worry about with some etching primers is that they don't take too well to some of the overcoat's that go over them. I couldn't tell you how a bedliner/undercoating would react with your High-Zinc etching primer. I have sprayed over Zinc based weld thru primer without incident.


Hope it helps, good luck!

The 2 part Rock-It liner sounds closer to what I am looking for. The problem with undercoat is what I have now, with it flaking off and carrying paint with it. Finally looked in a wheel well that I remember flaking a lot of the stuff out of, and of course I didn't come back and spray that area with anything 7 years ago. Got some rust action going on there.

Will be doing a video on using phosphoric acid on rust soon. Need to pick up some etching primer for those areas before getting into it, or some of that galvanize jazz and try it out. Going to be a few moons before I get into the heavy duty undercoating.

 

[318 Six Pack]

I use 95% cold galvanize spray on clean metal. I even use phosphoric acid ( OSPHO) on rusty areas that I can't get at to sand to clean metal. I've used the bedliner in 1 gallon can and brushed it on the inside of my trunk. If the original paint stays on after I use a wire wheel, I leave it on. This is on areas you normally wouldn't see. If it's body panels, I would take it down to bare metal. But hey I'm not making a show car. The bedliner in a can is a little thicker than regular paint, but it's pretty tough.

Is there an on-the-shelf cold galvanizing product out there? I stopped at both a paint jobber, NAPA, and Advance Auto with no luck. Online I see a Rustoleum product at a reasonable price. Will take a look at Lowes and Home Depot tomorrow.