What to paint frame with after sandblasting (2 Viewers)

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We thought that we had cleaned / degreased the frame pretty good prior to painting it, but apparently not.

We are seeing in some areas where it is chipping / flaking. We don't want to put the body back on to have it continue to chip off and start rusting again.

What paint would you recommend to cover it with that isn't going to break the bank.

Ultimately we would like to be able to brush the paint on. Several people have recommended an epoxy paint, but I don't know if you can brush that on. I know that several forums posts have talked about POR15, but I don't have any experience with it.
 
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Although it is more expensive, I'd look to see how much it would be to powder coat. It will hold up much better in the long run. I've seen that people have had good luck with the POR15 Chassis paint, though.
 
Yep without good prep nothing will stick to the problem areas. After sandblasting I use Tamco Chassis black epoxy paint. Has worked great on all my metal parts.
 
What exactly did you apply and how did you prepare the surface last time? This may be a better question to start with.
We used a degreaser several times to get off all of the grease and grime. Then we sprayed on a paint that a friend had left over that he said he had used in the past for chassis' with good luck.
 
*If $$ was no object and I had as much time as I'd like to work on my 40....I'd have the frame galvanized. (two big "ifs")
*Second pick would be powder coat.
*Third choice would be POR15. (although in my experience it runs/sags badly until dry unless painted on a horizontal surface)
*Fourth choice...(what I did) - after blasting I had the blaster immediately paint with red oxide primer. It sat in my pole barn shop for a couple years like that until I was able to swap it for the bent frame on my '77. It held-up well in a very humid environment. As I've done the frame swap ,(and cut off all the V8 stuff from the straight frame), I've used a combination of Spray Max two-part, spray bomb epoxy, rustoleum spray bomb semi flat black, and rustoleum brush-on tractor paint. (Well, the tractor paint isn't technically being used on the frame. I've used it on axles, springs, backing plates, trans, and bell housing. But I wouldn't hesitate using it on the frame.) I use the rustoleum semi-flat spray can over the epoxy because it's super easy to touch up. (I'm not restoring the 40....Just a "refreshing" that is taking way too long. I don't want to worry about scratching/scraping it up on trails.)

20140626_214205.jpg
 
On the frame it is spray bomb. On the axle and springs it's brush-on tractor paint. I've started using the brush-on paint on the front of the frame ahead of the firewall.
 
What paint would you recommend to cover it with that isn't going to break the bank.
For Texas pavement queen: any of the above with preference given to anything epoxy. Which are all brush on if mixed properly. Or, go to Napa and get 6 spray cans of epoxy paint. That’s good stuff.

For harsh use (salt exposure/off-road): sandblast, 2-3 coats of epoxy primer, 2-3 coats of Polyurethane. Urethane paints (POR, Chassis Saver et al) are the worst for this application.
 
i've never been impressed with powder coating chassis... in my experience it always ends up chipping and eventually scaling off. maybe these are examples of poor prep? just my experience. i ended up using an expoxy primer followed by an industrial epoxy paint designed for bridge/ high exposure structures. it's a nice satin black finesh
 
For Texas pavement queen: any of the above with preference given to anything epoxy. Which are all brush on if mixed properly. Or, go to Napa and get 6 spray cans of epoxy paint. That’s good stuff.

For harsh use (salt exposure/off-road): sandblast, 2-3 coats of epoxy primer, 2-3 coats of Polyurethane. Urethane paints (POR, Chassis Saver et al) are the worst for this application.

Most of that was correct, except for the urethane part. Acrylic urethanes will provide some of the best solvent and UV resistance available. That said, POR-15 is not a traditional Urethane product and shouldn’t be lumped in generically as a urethane. (Although I have equal disdain for POR).

The majority of modern 2k paints are urethanes.
 
We used a degreaser several times to get off all of the grease and grime. Then we sprayed on a paint that a friend had left over that he said he had used in the past for chassis' with good luck.

A few problems with this approach.

Degreasing should have happened prior to blasting, not after. (I’m assuming you blasted based on the title of this thread)

You used some random paint that your buddy had leftover without really knowing what it was and likely not following the manufacturer’s recommended prep


I would do the flowing:

Solvent wash
Blast to near white metal
Epoxy prime
Acrylic Urethane topcoat

Follow the recommended surface prep and other guidance in the tech sheets for the products you’re using. Don’t listen to some guy on the internet who says 10 coats is better than 2.
 
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If not on budget:
If you sandblast the best is 2K Epoxy primer. Period. It is the most dense of all primers. No primer is completely dense, but epoxy is by far the best. To rust, oxygen is needed from the air, so you have to shut the air out.
On top of that some 2K polyurethane. Not that important, bud need to be tough to protect the Epoxy which is what actually prevents rust.

If on budget, and no sandblasting:
Short and brutal answer: No paint will help in the long run. You must use a good rust-inhibitor, like Fluid Film to stop air and water penetrating.

I have a writeup on painting and rust protection here: Paint and rust protection
On Fluid Film here: Fluid Film

IMG_9471.JPG
 
*If $$ was no object and I had as much time as I'd like to work on my 40....I'd have the frame galvanized. (two big "ifs")
*Second pick would be powder coat.
*Third choice would be POR15. (although in my experience it runs/sags badly until dry unless painted on a horizontal surface)
*Fourth choice...(what I did) - after blasting I had the blaster immediately paint with red oxide primer. It sat in my pole barn shop for a couple years like that until I was able to swap it for the bent frame on my '77. It held-up well in a very humid environment. As I've done the frame swap ,(and cut off all the V8 stuff from the straight frame), I've used a combination of Spray Max two-part, spray bomb epoxy, rustoleum spray bomb semi flat black, and rustoleum brush-on tractor paint. (Well, the tractor paint isn't technically being used on the frame. I've used it on axles, springs, backing plates, trans, and bell housing. But I wouldn't hesitate using it on the frame.) I use the rustoleum semi-flat spray can over the epoxy because it's super easy to touch up. (I'm not restoring the 40....Just a "refreshing" that is taking way too long. I don't want to worry about scratching/scraping it up on trails.)

View attachment 2637240


Is it me or is the passenger frame horn bent ?
 
A few problems with this approach.

Degreasing should have happened prior to blasting, not after. (I’m assuming you blasted based on the title of this thread)

You used some random paint that your buddy had leftover without really knowing what it was and likely not following the manufacturer’s recommended prep


I would do the flowing:

Solvent wash
Blast to near white metal
Epoxy prime
Acrylic Urethane topcoat

Follow the recommended surface prep and other guidance in the tech sheets for the products you’re using. Don’t listen to some guy on the internet who says 10 coats is better than 2.
powder coat would not be my choice... to many corners and angles.. Once its compromised it starts to peel.. no way to easily fix... epoxy prime then topcoat.. Easy to spot repair and will last a long time...
 
I have used a kit from KBS Coatings a few times on a few projects including my 42. It includes a prep kit and paint. 5 years on in Canada’s salty north east, no problems. Very economical and easy to work with.
 
Not a ton of experience but I do know some industries have moved to zinc rich epoxy primer for the ultimate paint system. Heavy zinc fortified paint that creates a galvanic protection effect on the base steel.
 

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