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POR-15 where to stop???

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JOeyKnapp said:
Gerard, is "Blackshell" what you are referring to that you topcoated the Rust Bullet Silver with?

If I have clean metal do I need to worry with any prep other than good primer?

Also, it seems that your PM box is full. Is pixelsmith@gerardsgarage.com still a good contact email address for you? I need to find out about your Master Cylinder rebuild/resleeving.

thanks.
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Hi Joey,

Yes, Blackshell is what I used.

Most paints are porous. I think the paints that are formulated specifically as a barrier are a good idea, especially in cases where metal is not new and has rusted at some point. I've experimented with a lot of paints before and found that many, even when the surface looks good, will begin to rust underneath before long, even in fairly protected environments. I'd check the test result they demonstrate and decide for yourself. It might be overkill or it might be good insurance. I've found these couple have performed well for me. That's about all I can tell you. There are a couple less exotic paints in spray cans I like too, but they don't have the chemical/solvent resistance or hardness of Rust Bullet once it's cured.

It's fine to email me direct at that email address.
 
Timmy1959 said:
I like the Raptor from u-pol. I've used their products before and they work great. I'm wondering if it's transparent and the paint I add will get it red enough. I went to the U-pol site and they say you can add up to 10% of your paint to tint it. If it's black and you add only 10% percent, I'd expect a dirty red at best. Also here in southern California we're restricted to waterborne base coats. I wonder if that type of paint is will mix with the Raptor product. I doubt it. Any one know?
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The Raptor base has no color. It's essentially clear (not black). You would not be able to use a waterbased paint to tint Raptor, but there are actually certain solvent based paints that ARE legal in California. One of them is Dupont Nason, which is what I used. I'm sure there are others too. 10% is what I used, and as you can see from the picture, the difference in color against the painted areas is imperceptible.
 
I've not used the Ospho product specifically, but I assume is it some dilution of phosphoric acid that for which you pay a premium price. I always use phosphoric acid to clean and prep metal, I just use a generic brand I can buy by the gallon. Short answer, yes, you want to use a metal prep to clean and give the metal a "tooth" to get the paint to grip.
 
My Rust Bullet order is shipped! I got a few small cans of the auto, the black and one of the clear (to see what it was like..).

I will report back!
 
JOeyKnapp said:
On the same line of questions.. Do you use Ospho for treating any metal? If so, when and where?
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As stated above, Ospho is a brand of phosphoric acid like the Metal Ready product sold by POR. I buy a generic from my local agricultural supply for about 1/2 what the name brand products sell for. In addition to prepping panels with it I use it to remove rust from all sorts of fasteners and other hardware after having degreased it. Phosphoric acid is a very useful product during any restoration work.

The Marine Clean sold by POR is a very strong caustic cleaner. I found that the "ZEP Industrail Degreaser" sold by the gallon at Home Depot was equally strong and substantially less expensive. I use it all the time for any degreasing task on the car. It will however dry your hands out terribly so wear gloves.
 
I have a large part of the car sanded to bare metal. It hasn't seemed to have any surface rust yet, save a few spots that sweat dripped on.

At what point would I treat the surface with the Ospho/acid? Should I wait until I am ready to start the body work/bondo work? Or is it better to treat it now? (it seems like I read somewhere that once treated the metal would have tendency to rust over (but I don't completely remember what that was in reference to, I have done a LOT of reading lately..)).

I still need to get some pictures posted. Each day is going better and better. I did end up ordering the "rear closing panel" today. I knew there was some rust damage at the bottom, but on closer inspection it looks like it has been dented pretty good and beat out somewhat and quite a bit of bondo used on it. I would rather just replace the panel.

Thanks again guys for all the help.
 
Acid treat the surface now. Apply several coats of the acid using either a brush or pump spray bottle. KEEP THE SURFACE WET. Do not spray the surface and walk away. If you let the wet surface dry the resulting coating left behind will be loose and powdery and you will need to wash it off with more acid and scrubbing before you move on. You want to keep the surface wet as long as you can to develop a deep grey color. That indicates a good etch.

After the acid, wash the surface and immediately towel the surface dry followed by blowing it off with an air gun. You may get some amount of flash rust on the surface. Wipe the surface down with prep solvent or lacquer thinner and most will be removed. Any discoloration is not going to be a problem.

My preference is next to apply an epoxy primer to seal the surface and protect it. The epoxy will protect the surface indefinitely and can be scuffed up later for the application of high-build primer as you progress with the bodywork.
 
I like to do it exactly as Doug described. Any necessary body work, as in beating and bending, should have already been done but filler can be applied over the epoxy. In fact, it probably sticks better to epoxy than to bare metal.
 
Ditto what Doug and "Bayless" recommend. I follow the same process. Even if you can't paint right away, the phosphoric acid treatment will prevent or at least retard surface rust. You DO want to do the acid treatment shortly before the painting however to get the best adhesion.

Make sure you also wipe the areas to be painted with a degreaser made for that purpose. You want to wipe the surface with a white paper towels until they no longer show any color residue. You'll be surprised how dirty clean metal actually is until after you've made several passes with the degreaser. Automotive paint supply stores will have the product.
 
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