paint questions
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Joined: Aug 2011
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From: shelbyville mi
paint questions
well i hate the way my frame looks and you can really see it due to my bl. so i want my frame,rear end,and all other visible parts that might look bad, and i also want to spray under it with somthing to prevent rust, should i use paint or spray on bed liner for the floors? and what should i use for the frame? and what should i use to sand it? thanks
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Joined: Jun 2010
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From: Florida, USA
The new deal is baking soda blasting to remove all rust.
Too bad it is only for pros, a lot easier.
You can also use a stripper wheel that fits in a drill along with wire wheels, It is like a round spounge with carbide in it. Lasts a long time and really eats away crud. But remember - all bare metal must be primed or rust will eat it up. The rust you see on the frame is probably intentional because I know from construction that steel I beams are meant to rust a little, and the surface rust acts like a protective coating, to prevent deeper rust from the outside penetrating especially when embedded in concrete. I am not sure about trucks, but since almost every truck I have ever seen had surface rust on the frame and was not painted, I must assume it is intentional. So be careful with the frame thing.
As for body paint, I would prime and paint with automotive paint - two part urethane with hardener. Most of the frame rust is just surface rust, so flat black automotive urethane should do the job there also. The auto paint will stop rust from getting into the surface just like it does on the body, and if you have rust eating up from below, nothing on top will stop it anyway. Underocating is really meant for unpaintable hidden surfaces.
I have also used spray-on rust convertor. It turns surface rust into a good black color (and it paintable like primer) through a chemical reaction, and is supposed to prevent further rust. I have found it to work very well even on body rust where you just can't get to all the rust. Maybe that on the exposed frame? If you use that, don't remove the rust. I assume the rust is just superficial since there is no pic. You can get a small spray can and try it on a small area.
You know what the old song says "Rust never sleeps".
Too bad it is only for pros, a lot easier.
You can also use a stripper wheel that fits in a drill along with wire wheels, It is like a round spounge with carbide in it. Lasts a long time and really eats away crud. But remember - all bare metal must be primed or rust will eat it up. The rust you see on the frame is probably intentional because I know from construction that steel I beams are meant to rust a little, and the surface rust acts like a protective coating, to prevent deeper rust from the outside penetrating especially when embedded in concrete. I am not sure about trucks, but since almost every truck I have ever seen had surface rust on the frame and was not painted, I must assume it is intentional. So be careful with the frame thing.
As for body paint, I would prime and paint with automotive paint - two part urethane with hardener. Most of the frame rust is just surface rust, so flat black automotive urethane should do the job there also. The auto paint will stop rust from getting into the surface just like it does on the body, and if you have rust eating up from below, nothing on top will stop it anyway. Underocating is really meant for unpaintable hidden surfaces.
I have also used spray-on rust convertor. It turns surface rust into a good black color (and it paintable like primer) through a chemical reaction, and is supposed to prevent further rust. I have found it to work very well even on body rust where you just can't get to all the rust. Maybe that on the exposed frame? If you use that, don't remove the rust. I assume the rust is just superficial since there is no pic. You can get a small spray can and try it on a small area.
You know what the old song says "Rust never sleeps".
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Joined: Sep 2011
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OK, a bit to clarify here. I've been a car dealer and in the collision repair industry for the better part of the past 10 years. I've tried almost everything on my personal vehicles, my customers, and fleet vehicles, just to somewhat qualify that I know enough to offer legitimate information.
1) I'd advise against soda blasting your frame as it introduces an additional level of prep to neutralize the soda that you may or may not do correctly-we'll stick to idiot proof.
2) Do not use spray on bedliners or undercoating with no prep--no chemical adhesion, and poor mechanical adhesion means this stuff is a band aid and rust will bleed through. In my area its generally 3 weeks.
What the fella above me was referring to when he mentioned converters is a phosphating agent.
When you phosphate parts, it uses a primarily phosphoric solution to turn iron oxide (rust) to iron phosphate, which is inert. A good process for bare steel, or rusty steel. Knock off the scaling rust if attempting this. Remember to rinse with water after final application and fully dry before top coating. Products that phosphate: Naval Jelly, Ospho, SEM Rust mort.
After phosphating, a good 2 part epoxy is best.
Second, would be a sacrificial barrier coating like POR 15, Chassis saver, etc. You could save yourself the phosphating step if you went this route, but its a compromise, albeit one that is perfectly acceptable to most. Scrape the flaking crap off and paint; ie: POR (Paint Over Rust). Expensive though at over $100 a gallon--scroll down for cheaper alternatives. They do have poor UV resistance, but are good protectors and wont see the light of day anyway. The additives do fail eventually, so topcoating with something would be best.
Or, after phosphating you could just do a good ol' spray bomb attack with an enamel-rustoleum, etc. A urethane underneath would be ok, maybe unnecessary for the project unless you epoxy prime after phosphating. Its easy to make a mistake with prep, so I'd err on the inexpensive side to make touch ups and maintenance easy and cheap. Its easy to see if surface treatments fail.
Rust inside the frame rails is the deadly bad stuff, and most important as rust does the most damage from the inside out. It is always best to use a wax based rust preventative in the frame rails as 1) they last longer, 2) they do not seize hardware. A wax based rustproofer is what I'd do on the inside of the frame rails, heck everywhere. Hot melt stuff is best, but not available to most of us.
For readily available products:
You can buy the excellent GM OEM stuff in the form of
Dauert Nox Rust x-121. I'm not sure what Ford uses/used to use oem.
The farmer types love Fluidfilm, Aviation guys like LPS corrosion inhibitor-its the same thing, a waxy coating. There's also Amsoil MPHD, and corrosionX heavy duty, or corrosionx maxwax (which I'm suspicious is the exact same product as amsoil MPHD as they commonly rebrand)--all good stuff. I wouldn't put anything other than a wax based protector INSIDE my frame rails as it poses no threat to seizing any hardware. Put whatever you want on the outside, as it will be easy to see if it fails. Remember rust damages worst from the inside out.
I'd look them up and make a compromise on price vs. salt test rating if you're into research and want to save a few bucks.
You can buy the mil spec stuff: tectyl 846-Porsche uses it as a preventative. Or Tectyl 858 which is rated to -54C. Pricey. I'm not sure you can get it in small quantities.
If you want to got the DIY route You could also make homebrew waxoyl (my personal preference), which is parrafin wax, mineral oil or chain bar oil, and turpentine or mineral spirits mixed and sprayed on with a pesticide sprayer. It is essentially the same as the above wax type protectors, without the $15 a can price tag. There are recipes all over the net.Cheapest and best protection you'll get for the $$ if you're the DIY type.
In the end, you could just take the extremely easy way out: go nuts with a wire brush for an hour or so, then shoot a half dozen cans of Rustoleum rusty metal primer all over the place --let that dry and encapsulate the whole works with homebrew waxoyl or spray inhibitor like i stated above. Wax is waterproof and air tight. It is also self sealing, it will flow into voids if gouged.
1) I'd advise against soda blasting your frame as it introduces an additional level of prep to neutralize the soda that you may or may not do correctly-we'll stick to idiot proof.
2) Do not use spray on bedliners or undercoating with no prep--no chemical adhesion, and poor mechanical adhesion means this stuff is a band aid and rust will bleed through. In my area its generally 3 weeks.
What the fella above me was referring to when he mentioned converters is a phosphating agent.
When you phosphate parts, it uses a primarily phosphoric solution to turn iron oxide (rust) to iron phosphate, which is inert. A good process for bare steel, or rusty steel. Knock off the scaling rust if attempting this. Remember to rinse with water after final application and fully dry before top coating. Products that phosphate: Naval Jelly, Ospho, SEM Rust mort.
After phosphating, a good 2 part epoxy is best.
Second, would be a sacrificial barrier coating like POR 15, Chassis saver, etc. You could save yourself the phosphating step if you went this route, but its a compromise, albeit one that is perfectly acceptable to most. Scrape the flaking crap off and paint; ie: POR (Paint Over Rust). Expensive though at over $100 a gallon--scroll down for cheaper alternatives. They do have poor UV resistance, but are good protectors and wont see the light of day anyway. The additives do fail eventually, so topcoating with something would be best.
Or, after phosphating you could just do a good ol' spray bomb attack with an enamel-rustoleum, etc. A urethane underneath would be ok, maybe unnecessary for the project unless you epoxy prime after phosphating. Its easy to make a mistake with prep, so I'd err on the inexpensive side to make touch ups and maintenance easy and cheap. Its easy to see if surface treatments fail.
Rust inside the frame rails is the deadly bad stuff, and most important as rust does the most damage from the inside out. It is always best to use a wax based rust preventative in the frame rails as 1) they last longer, 2) they do not seize hardware. A wax based rustproofer is what I'd do on the inside of the frame rails, heck everywhere. Hot melt stuff is best, but not available to most of us.
For readily available products:
You can buy the excellent GM OEM stuff in the form of
Dauert Nox Rust x-121. I'm not sure what Ford uses/used to use oem.
The farmer types love Fluidfilm, Aviation guys like LPS corrosion inhibitor-its the same thing, a waxy coating. There's also Amsoil MPHD, and corrosionX heavy duty, or corrosionx maxwax (which I'm suspicious is the exact same product as amsoil MPHD as they commonly rebrand)--all good stuff. I wouldn't put anything other than a wax based protector INSIDE my frame rails as it poses no threat to seizing any hardware. Put whatever you want on the outside, as it will be easy to see if it fails. Remember rust damages worst from the inside out.
I'd look them up and make a compromise on price vs. salt test rating if you're into research and want to save a few bucks.
You can buy the mil spec stuff: tectyl 846-Porsche uses it as a preventative. Or Tectyl 858 which is rated to -54C. Pricey. I'm not sure you can get it in small quantities.
If you want to got the DIY route You could also make homebrew waxoyl (my personal preference), which is parrafin wax, mineral oil or chain bar oil, and turpentine or mineral spirits mixed and sprayed on with a pesticide sprayer. It is essentially the same as the above wax type protectors, without the $15 a can price tag. There are recipes all over the net.Cheapest and best protection you'll get for the $$ if you're the DIY type.
In the end, you could just take the extremely easy way out: go nuts with a wire brush for an hour or so, then shoot a half dozen cans of Rustoleum rusty metal primer all over the place --let that dry and encapsulate the whole works with homebrew waxoyl or spray inhibitor like i stated above. Wax is waterproof and air tight. It is also self sealing, it will flow into voids if gouged.
Last edited by Muskrat80; Sep 21, 2011 at 09:18 PM.
