Acid etch primer over bondo?

[brickyard69]

Is it ok to spray acid etch primer over bondo?

I have an area I repaired and there is both bare metal and bondo. I plan on covering the entire car with ureathene primer before topcoat.

Thanks

[Rick Giles]

Most all acid etch primers should not be sprayed directly over body plastic. I sell PPG products and also Sikkens and neither one recommend spraying directly over it but some slight overspray will not hurt. Just be sure to give the etch primer plenty time to flash before you spray your urethane primer. At least 30 minutes @ 70 degrees. That way the acid can evaporate out of the body plastic.

[parsonsj]

Yep, that's what the product sheets say for PPG. Light overspray over body filler, but no more than that.

jp

[brickyard69]

This is the product I am using.

It says ok to put over polyester filler.

http://www.ppg.com/TdsAutoColor/Show...alCode=44&SS=1

[RobM]

i would use a metal conditioner with an epoxy primer, epoxy is awesome and its body filler safe

[Rick Giles]

I agree with RobM.

[gmachine68]

thanks for the input, but he has already done his body work and wants to add some corrosion resistance to his bare metal areas in the featheredge. yeah metal conditoner and epoxy is ok, and is what you have to do when using polyester primer but 95% of guys out there do not use polyester often so etch primer gets used, then onto urethane primer
jake

[brickyard69]

gmachunes68 you are correct.

[BRIAN]

Try PPG NCP line it is etch,surfacer, and sealer all in one. Medium build and really sticks to anything. Actually they may have changed line name but it is easy one product straight though. The new lead free epoxy isn't as good as the old DP line.


Actually you really shouldn't get conditioner on plastic either as the plastic can swell. It is one of those gray areas where you just try and keep the overspray to a minimum.

[mikey]

I've been putting light coats over my entire panels for the last 15 plus years with no problems.That way I'm sure to cover all bare metal. Light enough that you can see the shadows of whats underneath. Btw I use dupont variprime followed by uro prime.

[RobM]

cant you lay your epoxy before you use filler? Put the filler over the epoxy base?

[gmachine68]

rob, yes epoxy can have filler applied over it, i like to sand it with 80 grit before filler but some use 180, epoxy does have some corrosion resistance which is good, epoxy is best for projects that take time because 2 coats will seal it up to mother nature then as you body work each panel you can sand it and do whatever needed to get it ready for primer.
jake