[Havoc]

Some parts of my roof are starting to get a little surface rust through the light coat of primer that was put on 10 years ago. Since I plan on sanding the roof down tommorrow, I wanted to know a little bit about epoxy primer. Can it be applied with a regular gun? (My dad also has a turbine HVLP sprayer) Can you paint over it with laquer or urethane, or just epoxy based paint? Also, how much should I expect to pay for a gallon of it? Does it sand easily? Anything else I need to know? Thanks.

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Ian McDermott
1970 Chevelle SS 396
Columbia University
New York, NY.
E-mail: [email protected]
Web page: drive.to/chevelle
ICQ UIN: 3923441

 

[Wes V]

Havoc;

Use PPG DP90. Yes, you use a standard paint gun for it.

It sprays real well, but count of a couple of layers for solid coverage.

Yes, you can paint right over it.

Just DON'T spray it over the surface rust and also (as you said) sand off all the prior primer.

Wes.

 

[JWagner]

There are several types of epoxy primers. One is the self-etching primer which is put directly onto the metal; this stuff is very hard and is not intended to be sanded. The second type is a sandable filler/surfacer which is intended to be put over the first type. I would not put an epoxy etching primer over any other paint, but I might try putting the sandable stuff on top of an older but solid paint. Got this info from an evening course in body repair I took years ago.

 

[elcamino72]

Wes & JWagner have a good idea. The DP 90 is great. But it is expensive, A quart of primer will cost you 25 and the hardener will also cost you 25. So you are looking at a $50 Quart of primer. It is a very good primer. It is self-eching, and shouldn't be sanded. However, if you do make a mistake you can sand just a little bit.

 

[ehjorten]

I have found URO Prime to be a very good epoxy primer. It is a three part catalyzed epoxy primer from Dupont (if memory serves). Be aware that any catalyzed epoxy primer is going to be somewhat expensive, but well worth it!!! For a superior long lasting finish remove all paint to bare metal, then use a phosphorus acid metal wash (Ospho, 3M metal wash, etc...). This will remove any microscopic rust. Sanding does a good job, but there is still rust that you can't see with the naked-eye. Then prime! This will provide a superior base for your finish. It is a little more work, but well worth it and a much higher quality base than you will get from even the most reputable shops!

 

[ELLI]

While I have never used PPG epoxy system Im sure it is an excellent product. Everything else our theirs I have used was excellent. What I have used is Duponts system. First use Variprime, that is their self etching primer to be used over bare metal. When you spray it you will know why they call it "yellow death". Then after about 30-45 minutes spray URO primer over it. URO is a 3 stage primer, that is easily sanded. Like the others said the stuff is not cheap. Variprime is $28 bucks per qt plus 18 buck for activator, and URO is $39 per quart plus $18 for converter plus $24 for activator, but the stuff spray like a dream and sands easily. All told I used 3 quarts of variprime and 7 quarts of URO prime for a complete car, but my sheetmetal is straight as an arrow. The stuff is expensive and will only get worse as the new low VOC laws take effect. It has already affected the availability of sealer and clearcoat from DuPont. Its probably only a matter of time before you wont even be able to buy the stuff over the counter anymore. Mat ACES #2424

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[tom wurm]

Make sure you wear a good respirator.