spraying epoxy primer

[TheDude]

back from the sand blaster, I have to get this thing primed quickly, the air is already causing a slight return of the rust, so I need to get it primed asap.

I am using epoxy primer, the auto body supply shop sold it to me for $50 a qrt, did I get taken? I'm in this $100 and I don't think two quarts is enough for the cab, is it?

How many quarts does it take to prime a truck?

I am using a $15 harbor freight spray gun, which is working quite well, but without any experience I don't know if primer is getting wasted or not.

Thanks!

[OrrieG]

I have used 3/4 of a gallon and still have the hood and bumpers to do. I did some areas (doors and parts of the cab twice because I sanded thru to get rid of some runs). Can't remember the individual prices but I paid almost $300 for etch primer, sanding primer and associated reducers, etc. Still have some of each left. Go slow with the epoxy the runs are VERY hard to sand down when cured. If it is surface rusting you need to wipe it down with something to get rid of the rust. Old school is a reduced solution of muritic acid, but I think there are modern equivlents. I have something the paint guy recommended and have not seen any sign of the rust coming through.

[TheDude]

So as far as primer goes, can I use the cheap rattle can stuff to just get it covered, and when i have some time and money, go back and do the epoxy primer?

[Dan in Pasadena]

Originally Posted by TheDude

So as far as primer goes, can I use the cheap rattle can stuff to just get it covered, and when i have some time and money, go back and do the epoxy primer?

On perfectly clean, newly sandblasted metal? I think the answer ot that is a simple, NO. I DON'T think you want to do that.

[TheDude]

Originally Posted by Dan in Pasadena

On perfectly clean, newly sandblasted metal? I think the answer ot that is a simple, NO. I DON'T think you want to do that.

why not??

[tmoble]

moisture will penetrate that rattle can primer. that's really the advantage of the epoxy type primer, it isn't penetrated by water or moisture.

[TheDude]

eh, just for the time its in the garage, the rattle can will hold up, no?

[OrrieG]

Originally Posted by Dan in Pasadena

On perfectly clean, newly sandblasted metal? I think the answer ot that is a simple, NO. I DON'T think you want to do that.

Only if you want to sand it all back to metal. I used rattle can etch thinking it was the same and ended sanding it all off. Tmoble is right, I had my doors in a weather tight shed, in the desert (we get 14" of moisture a year, mostly snow), and still had surface rust under the rattle can etch. It will minimize it but not totally protect.

[TheDude]

point taken, so it looks like eastwood has a gallon epoxy primer kit for $100, they say its sandable, the stuff i used so far was 100 for two quarts, anyone had any luck with the eastwood product?

[MrTucker]

maybe it depends on what rattle can you use. I wire wheeled a couple areas on my cab, used a somewhat expensive etch primer (cant remember the brand, about $8 a can) and no rust has returned or any bubbling. The cab has been out in the rain a couple times and it's been almost a year. but at $8 a can, you'd spend far less by mixing and spraying your own primer...

[Elder Rogue]

I have not used this product but have heard good things from those that have.

http://www.southernpolyurethanes.com/index.htm

In the past I have always used DP90 but I am going to use their epoxy primer on my current project.

[justplainray]

check out Summit Racing products,
I've used both their epoxy and polyureathane primers.
Both are of good quality and price is not to bad.
FYI.
Store freshly stripped parts indoors.
Use phosphoric acid to ecth light surface rust before primer.
You can get ph. acid at Home Depot reasonably priced by the gallon.
Rattle can paints are of low quality, don't use them as base/foundation coats.

IMHO
justplainray

[MrDude_1]

Originally Posted by TheDude

point taken, so it looks like eastwood has a gallon epoxy primer kit for $100, they say its sandable, the stuff i used so far was 100 for two quarts, anyone had any luck with the eastwood product?

Along with seeing others results, I have been doing alot of research on Epoxy primers for the last 3 years.
The one I would go with is SPI Epoxy primer. You can read their tech sheets on it at their website: www.southernpolyurethanes.com
To my knowledge, you normally cant buy it directly from them, but most paint supply shops either carry it, or can get it. Very cool, very tough stuff.. and it takes paint over it well...

[MrDude_1]

Originally Posted by justplainray

Store freshly stripped parts indoors.
Use phosphoric acid to ecth light surface rust before primer.
You can get ph. acid at Home Depot reasonably priced by the gallon.

The acid etch depends on the epoxy primer you use.
On some Epoxy Primers, you shouldnt use acid etch. They should go to bare, clean metal.
For example the SPI one I just posted about, adheres and protects better without acid etching. Same thing with POR and similar paint over converter products too.