Bare metal epoxy primer for truck frame

[Hay Dude]

Getting ready to paint a sand blasted steel truck frame.
Need advice on what bare metal epoxy primer to use.

Frame was rusty and needs prep work. Any professional advice for preparation appreciated.

 

[Roadworthy]

Check with a local auto paint supplier or body shop. Some primers are made to bond even to rusty areas.

 

[IH3444]

HayDude, Have used this product with excellent results.

Products

www.loctiteproducts.com

https://www.lowes.com/pd/LOCTITE-Rust-Neutralizer-10-2-oz-Rust-Remover/4764091

 

[Hay Dude]

Im hearing products like POR-15 cover rust and make it worse, but that could be rumor. I am planning on having all the rust removed with sandblasting, but it wont be like new metal, either.

 

[3Ts]

If you're getting it sandblasted, will the sandblaster prime it? If not, you'll probably get it back with a flash coat of rust on it. That would be ideal for a Phosphoric Acid treatment (Oshpo). That will convert the rust (iron oxide) to iron phosphate which clings very tightly to iron and makes an excellent primer.

 

[Hay Dude]

The sandblaster offered to prime it and has a paint booth.

I would think right after sandblast, it should be blown off and wiped down?

 

[dodge man]

If it’s sandblasted clean I would have him prime it. It would be important to get any sand off it and no grease. It seems like sand gets in and nooks and crannies so it would take some time. Good primers often say something like “self etching”.

Keep in mind most primers won’t keep water out. It will stop tge surface rust for a short time but it should be painted pretty quickly.

 

[Carl_NH]

Had my mower deck sandblasted then coated with 2 part epoxy primer per the SB guy epoxy is best over SB metal. You don't need metal etching primer and epoxy is harder. The only caveat is most epoxy primers recommend painting within 48 hours of application, otherwise if longer than a few days, they suggest to sand the primer for adhesion.

 

[crashz]

The sandblaster offered to prime it and has a paint booth.

I would think right after sandblast, it should be blown off and wiped down?

Yep - Wouldn't hurt to have him paint it too. Then you don't have to move the truck, re-clean the frame and paint it.

I'm a fan of the Chassis Saver by Magnet Paint and Eastwood products. Eastwood will have a good etching primer, then follow up with a a good paint (like their chassis paint or Chassis Saver). Not cheap, but good stuff.

And even though it will make that nice new paint look like garbage, a top coat of Fluid Film Black or NH Oil Undercoating will keep the rust from coming back. You'll want to paint first, but you'll want a penetrating oil to get in between the frames.

 

[nyone]

Im hearing products like POR-15 cover rust and make it worse, but that could be rumor. I am planning on having all the rust removed with sandblasting, but it wont be like new metal, either.

If your not taking the frame off the body dont bother. There will be many places you cant sand blast and cant paint. All it takes is one rock and your paint is gone.
Woolwax or Fluid film work well, are self healing to some extent and you can spray areas you cant normaly get to.

Yes POR 15 sucks. The amount of prep work to get it to work properly is the same as normal paint..and your one rock chip away from failure.

 

[Snobdds]

If you can't paint the expoxy primer in 3-4 days...don't use it.

For a truck frame, just a good high build primer is fine. Then use an industrial coating, like JD industrial Black, for a top coat.

It's really more about mil thickness. You want a lot of primer and paint on a frame. The more the better.

 

[Hay Dude]

So sandblast, wipe down, keep inside, then use self-etching epoxy primer, then topcoat in less than 48 hours?

 

[Snobdds]

essentially.

They say you have 7 days to top coat an epoxy primer, but I think it's more like 3-4 days.

I guess it kind of depends on the spray booth. My buddies is capable of doing both sand blasting and painting. If that is the case, you don't have so much exposure to the air. It's not a frantic rush to get primer and top coats on to prevent flash rusting.

 

[mrmikey]

If I remember correctly it was an epoxy primer they used when they sandblsted a body where I used to work. They'd paint it immediately after blasting. By immediately I mean less than 24 hours, it would leave the heated sandblast shed after being blown off and go right into the heated paint booth. Even then, in a warm, muggy summer day it would get a rust haze on it. The finish coat would get sprayed the next day as the primer was left to cure overnight.
As was mentioned too, a good liberal coat of Fluid Film, Rust Check or some other type of creeping coating after you mount the body as you don't want to be crawling around a slimy truck trying to weld, plumb and wire a body.

 

[Hay Dude]

I was referred to a guy who owns a business that oil coats the entire underside of the truck. He said he can pressure inject oil in between the frame rails from the top and coat everything for $250.

I think that it may be wise to get something between the frame rails, if it’s even possible….
They will dill holes in door jambs and put an oil mist inside the doors, coat the entire underside of the truck.

 

[mrmikey]

He said he can pressure inject oil in between the frame rails from the top and coat everything for $250.

IMHO, one of the best thigs you can do. Oil or similar viscosity substance will creep, unlike paint or any product the hardens or sets.
I remember seeing something on the 'net a couple years ago. This fella would drill and tap a 1/4"unf thread hole in the middle of the outer frame web every couple of feet and screw in a grease nipple. He had a pneumatic grease gun geared up with waste oil and would inject oil between the rails. It looked messy for him but it looked as if the oil was coming out between the flanges after a couple of days. It had to have helped some.
I'd wait until you get the body mounted tho, like I said, its a pia when you attempt to work on a truck that's just been undercoated. I've taken a few tumbles off a truck frame when working on a truck that someone had just done. Come to think of it.....that explains a lot .

 

[Hay Dude]

I think thats what this boy does. Sounds like cheap insurance. Metal loves oil.

 

[dirttoys]

POR15 has a cleaner, converter/prep and the paint on rust material. It is 3 real steps, but if you do the prep it lasts a long time, and is hard enough to take rock chips better than paint.

If you are going to sandblast, just the metal prep and the por15 itself will be good.

I did a 03 f150 I still have, and it has held up well.

Best,

ed

 

[nyone]

I was referred to a guy who owns a business that oil coats the entire underside of the truck. He said he can pressure inject oil in between the frame rails from the top and coat everything for $250.

I think that it may be wise to get something between the frame rails, if it’s even possible….
They will dill holes in door jambs and put an oil mist inside the doors, coat the entire underside of the truck.

Many vehicles you dont need to drill acess holes. I have done 4 vehicles with woolwax and didnt need to drill anything. Theres plenty of body acess plugs in alot of vehicles.

For the tiny acess holes like the bottom of doors get a spray can of woolwax with the 360* straw.

You are getting kind of late in the season to do this type of thing now. Generaly I like to do this in the summer. Warm woolwax or fluid film creeps and sprays better when warm.

 

[Tinhack]

If you can't paint the expoxy primer in 3-4 days...don't use it.

They say you have 7 days to top coat an epoxy primer, but I think it's more like 3-4 days.

Back when I was painting, overcoats to any epoxy had to be performed within 8 hours or less or it wouldn't stick. I spent many long days when using epoxy primers and paints. I spent 20 hours on one event when I painted a boat. I wouldn't do that again.