epoxy paint ?'s

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dazedduster

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ok, i have nason epoxy paint (only kind i can get here) is says non sanding.
it that true for all epoxy paint. i want to put it on my duster do my body work over it. will this work.
 
Most epoxy primers I have used are non sanding... they sand like bubble gum. Lots of people suggest "sandwiching" your body filler in epoxy primer... bare metal covered with epoxy, bodyfiller, epoxy primer. Never made much sense to me as a body man.. First you spray the panel with epoxy... let it dry, then to get the filler to stick you have to sand epoxy. By the time you are done doing your filler work you will have most of the epoxy sanded off in my opinion. Seem's like a good concept for rust but not very user friendly. I would suggest doing your bodywork and finishing with a coat of epoxy, or a good corrosion resistant primer such as PPG Ncp170
 
67Dart440GT said:
Most epoxy primers I have used are non sanding... they sand like bubble gum. Lots of people suggest "sandwiching" your body filler in epoxy primer... bare metal covered with epoxy, bodyfiller, epoxy primer. Never made much sense to me as a body man.. First you spray the panel with epoxy... let it dry, then to get the filler to stick you have to sand epoxy. By the time you are done doing your filler work you will have most of the epoxy sanded off in my opinion. Seem's like a good concept for rust but not very user friendly. I would suggest doing your bodywork and finishing with a coat of epoxy, or a good corrosion resistant primer such as PPG Ncp170
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Agree with the above ^.

Non-sanding if you're going to recoat within the "window" of time allowed.
Which is what 3-7 days for some? If you go beyond that you'll have to scuff it. Which, as pointed out, is like sanding bubble gum.

Been a long time since I've used epoxies. But that's personal preference along my lines of experience. I gave up on epoxies when the old DP bit the dust and was replaced with the new DPLF. The old DP I think you could have reduced with piss and still gotten good results as a sealer to bare metal straight to color.

As was stated above I'd rather use a corrosion resistant urethane like was mentioned in the NCP line. Reduced it lays in nicely. Unreduced you can shape it almost like a glazing putty.
 
I have used PPG epoxy (DP) quite a bit. You are correct that it does not sand. If recoated within 7 days you do not have to do anything. I have used fillers right on top of the epoxy with no prep within the 7 day window. After 7 days I use a wax and grease remover to clean, then scuff with a green scotchbrite pad, reapply a coat of epoxy then your 7 days window begins again.

I generally strip a panel to steel, spray a coat of epoxy, use any filler that needs to be applied, then another coat of epoxy; and primer surfacer on top of that.

Here is some useful info for the ppg product:
http://www.tcpglobal.com/kustomshop/images/DOCS/P-122.PDF

and i think this is the info for the nasson:
http://pc.dupont.com/dpc/en/US/html/visitor/common/pdfs/b/product/nsn/Nason/491-35.pdf
 
When ever I get a part back from the blaster I suff it then seal it up with a reduced coat of dp (or if I know something needs to be water proof) then do what ever finish body work on top of the dp after I scuff it with 80 grit, then do my primer and seal it with another coat of reduced dp then paint right on top of the dp. I use 401 (I believe, its the catalysis that has to sit for 1/2 hour before you can spray the dp not the 402 that is spray-able as soon as you mix it * It's been a long week and I could have those mixed up, I honestly can't remember right now) Anyway and then the base goes on right over the fresh top layer of dp.
 
We have 4 experienced body men chime in on this with differing experiences and opinions. One of the reasons I like to say "from my experience" when addressing subjects like this. A lot of times it comes down to the preference of the person. Body work is definately one of those fields in which you might have five experienced guys do five different things and the results come out fairly the same.
 
If its bare metal I just apply Filler right on that, then apply a coat of epoxy then the next day come back and spray it with a high build primer to be blocked. Then when you go to block once you hit the epoxy stop sanding that area(same concept as if you hit metal).

As stated all bodymen are going to have different opinions on this, Thats how I do it at work.
 
Im not a pro bodyman but I like to have some kind of primer under my filler. It is an extra step and a waste of product seeing that you will sand some of it off but I like the peice of mind knowing that the metal is protected. Time is money to a bodyshop and extra product sanded off into dust cuts into profit thats why most pros don't do it like this. If the car will never see salt or rain then you can probably fill over bare metal, just make sure moisture can't get behind the filler.
 
daliant said:
Im not a pro bodyman but I like to have some kind of primer under my filler. It is an extra step and a waste of product seeing that you will sand some of it off but I like the peice of mind knowing that the metal is protected. Time is money to a bodyshop and extra product sanded off into dust cuts into profit thats why most pros don't do it like this. If the car will never see salt or rain then you can probably fill over bare metal, just make sure moisture can't get behind the filler.
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I like this statement. I feel the need to ask what I feel is a reasonable question about this statement since I've heard it so much.

Let's say you don't prime under the filler, okay. But the metal is clean and well etched, say with a grinder disk, acid etch, sand scratches from the DA, whatever. You've done your filler work and now lay down a bare metal resistant surfacer. Okay, let's say you laid down a bare metal primer, then went to surfacer. You've done your block work, now you put sealer on it, color, then clear. So, with today's improved fillers (not cheap *** Bondo, but something good) we need to concern ourselves with moisture going though the clear, the color, the sealer, the surfacer, the bare metal primer of your choice, eating through the filler then attacking the bare metal underneath? Then why don't we need to worry about the moisture going through all those same layers of paint and primer and attacking the rest of the bare metal underneath all those paint layers on the whole car where there's no filler?

I'm not saying that using primer under the bone is right or wrong. Like I've stated before in this thread, you'll hear different answers from experienced guys who rely on experience and preference. I just want someone to explain to me how the moisture is going to make it's way through all the paint and primer above the filler and not on the rest of the car.
 
The only way moisture can get behind the filler is if the filler is exposed from behind the panel like if moulding holes are filled in or through any holes that aren't welded up, which is going to cause problems regardless of prep to the finished side of the panel. I like to prime before filling because most of the stuff that I work on comes from the rustbelt and has surface rust, pits, etc... so after I kill the rust with ospho I etchprime then fill. If the panel is rust free then priming before filler is a waste of time and materials.
 
daliant said:
The only way moisture can get behind the filler is if the filler is exposed from behind the panel like if moulding holes are filled in or through any holes that aren't welded up, which is going to cause problems regardless of prep to the finished side of the panel. I like to prime before filling because most of the stuff that I work on comes from the rustbelt and has surface rust, pits, etc... so after I kill the rust with ospho I etchprime then fill. If the panel is rust free then priming before filler is a waste of time and materials.
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You just told me what I wanted to know and then some.

By the way, you did see where I live, right? I know all about the rust belt.
 
Lots of times a "restoration" job takes time... hence a panel sitting in bare metal for a few days minimum... your moisture,oil, contaminants, don't need to penetrate from the top down. A panel will actually start corrosion in a very short amount of time. The rusting issue will come from beneath not from the top. A good body man can do filler work on top of bare steel with no corrosion issues. I have done it for 15 years with no rust issues ever. As long as the panel is coated quickly without sitting for very long it will be just fine.
 
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