[Riot Racing]

This is my second time using the POR15 products. I have been wanting to ask these questions for a while but never got around to poting the pictures.
Here is a piece that I had snadblasted but decided to us the POR15 stuff anyways.

This picture is to demonstrate what the metal looked like after I use the Marine Clean then the prep and ready product. The Marine clean soaked on the material for 30mins then was rinsed off with water. Then, I sprayed the Prep and Ready and let that soak for 45mins. Rinsed with water and let sit overnight. I did the prep work on night so sitting overnight just ended up happening it is not a requirement. Before painting I used a wet towel to clean the "powdery" surface. I let the parts dry in the sun before painting.


here is a close up of the material after the Prep and Ready has done it's thing:


Does this light oxidation look right? Do you think I used the prep materials correctly?

HERE ARE MY REAL CONCERNS:
Both times I have used the POR15 products and the same process described above I get these weird bumps in the paint. It almost looks like "Goosebumps" on your skin.
I applied two coats of paint. The first coat dried for 3-4hrs because the temperature was around 70degrees outside that day. The second coat dried over night. The bumps were not really noticeable at the time I went to apply the second coat.



Does anyone know what these bumps are happening in my paint? Will the bumps not show when I apply the topcoat, which will be POR15 Hardnose?

[killeratrod]

either not prep right or over worked the por15 and made air pockets. it should be self leveling . just my thoughts

[mitmaks]

Did you run cloth/rag over sandblaster surface? That would result in lint being stuck on rough sandblasted metal. Once you apply coating over it, it would look like little bumps (lint under paint)

[Riot Racing]

Originally Posted by killeratrod

either not prep right or over worked the por15 and made air pockets. it should be self leveling . just my thoughts

I considered that but kind of doubt this is what caused it. The first pieces I POR15 had this same issue and I only applied 1 coat of POR15 to that surface and the bumps were even worse than these pieces.

Originally Posted by mitmaks

Did you run cloth/rag over sandblaster surface? That would result in lint being stuck on rough sandblasted metal. Once you apply coating over it, it would look like little bumps (lint under paint)

I used a wet rag to clean the sandblasted metal. I then used a Tack cloth once the metal was dry to make sure there was no contamination on the metal. I am skeptical that these bumps are lint.

[496CHEVY3100]

Originally Posted by Riot Racing

I considered that but kind of doubt this is what caused it. The first pieces I POR15 had this same issue and I only applied 1 coat of POR15 to that surface and the bumps were even worse than these pieces.



I used a wet rag to clean the sandblasted metal. I then used a Tack cloth once the metal was dry to make sure there was no contamination on the metal. I am skeptical that these bumps are lint.

You did not mention if you used sand .soda glass ,or walnut shells,on small panel such as the one in picture i have glass in my cabinent with no problems,also coat with por 15 ,i spray mine one coat only . i have seen good results with brush ,if uou used sand with silica it needs to be washed with dx330 ar similar prodect to remove silica ( posion ) when i use sand i use play sand ,non toxic leaves no residue,.possibly wiping with wet ,water ,rag you might be just spreading contaminates, ,there are many opinions ,this is mine after 40 + years.

[Gringo]

I've been using por15 for years and never seen anything like this. Did you shake the can? You can't do that because you get air bubles in the paint. You have to stir it really well but in a slower motion. I've had really good results and I love the stuff. I should mention that I don't use the prep stuff. I also have never sprayed it. It flows out like glass with a brush. I paint right over rust. Use a lot of paint as in a heavy coat and apply 2 or 3 coats. Recoat when coat is just tacky enough to leave your finger print.

[496CHEVY3100]

I also brush the frame works great,but i spray it when it will be top coated with paint,must be covered if exposed to sun , Sun uv rays will work but shortens life. Great product i think.

[Riot Racing]

Originally Posted by 496CHEVY3100

You did not mention if you used sand .soda glass ,or walnut shells,on small panel such as the one in picture i have glass in my cabinent with no problems,also coat with por 15 ,i spray mine one coat only . i have seen good results with brush ,if uou used sand with silica it needs to be washed with dx330 ar similar prodect to remove silica ( posion ) when i use sand i use play sand ,non toxic leaves no residue,.possibly wiping with wet ,water ,rag you might be just spreading contaminates, ,there are many opinions ,this is mine after 40 + years.

Company blast the parts. They told me they were going to use Aluminum Oxide for blasting.
I have never heard of cleaning the parts after blasting with anything more than water. I have never heard of dx330.
I thoguht about spray this stuff, but because the metal doesn't show I wasn't too worried it it didn't come out looking good.
I thought "Play" sand has even more silca in it then glass bead?

Originally Posted by Gringo

I've been using por15 for years and never seen anything like this. Did you shake the can? You can't do that because you get air bubles in the paint. You have to stir it really well but in a slower motion. I've had really good results and I love the stuff. I should mention that I don't use the prep stuff. I also have never sprayed it. It flows out like glass with a brush. I paint right over rust. Use a lot of paint as in a heavy coat and apply 2 or 3 coats. Recoat when coat is just tacky enough to leave your finger print.

I think i did shake the can a little forgetting that you are not suppose to.
Doesn't the POR15 instruction say to apply in thin coats but apply at least 2-3 coats allowing time for the paint to "tack" in between coats?

[496CHEVY3100]

Dx330 is just a grease and wax remover,anybodys product would work ,just dont let it dry wipe on wipe off, Play sand does not contain silaca .it us banned in all exept industrial use here,then you must use partical respeatorr not dust mask,,never used alum oxide most people who have used it have no complaints.hope ypu solve your problem ,post when you find iy.

[Larry123]

Maybe you could chip or cut one of the bumps off and see what's underneath, you might find your answer. Sand, air, rust.

[Lizer]

anything should be degreased before painting it. Water is the worst thing you can use; it doesn't lift away or solubilize hydrophobic contaminants, and just results in the freshly blasted metal flash rusting.

[Riot Racing]

Originally Posted by Lizer

anything should be degreased before painting it. Water is the worst thing you can use; it doesn't lift away or solubilize hydrophobic contaminants, and just results in the freshly blasted metal flash rusting.

POR15 instructions state to rinse the parts with water after each step of the process i listed

[dinger]

Some look like air pockets, some look like sand particles. Grab an ice pick and start probing. Air pockets may be from a contaminated surface.

Directions on a product are great when they work. These products are going to give simple instructions or most folk are not going to buy the product. Dawn is a good grease cutter. Many paints can't be shaken, they must be stirred. Regardless, until you figure out where you went wrong, this will continue to be a problem. A little sandpaper over the problem areas, a little probing with an ice pick, you should find the problem, then touch up from there.

[Alpha67]

Looks like trapped air bubbles to me which can happen if you shake the can. It can also happen when applying to heavily with a brush (or depending on brush strokes) according to a comparable product I have used

[496CHEVY3100]

Originally Posted by Riot Racing

POR15 instructions state to rinse the parts with water after each step of the process i listed

But not before 1ST coat .i avoid water and use grease and wax remover, you can use it however works for you. just my opinion