Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (http://www.hotrodders.com/forum/)
-   Body - Exterior (http://www.hotrodders.com/forum/body-exterior/)
-   -   Do you need etching primer under featherfill primer? (http://www.hotrodders.com/forum/do-you-need-etching-primer-under-featherfill-primer-25937.html)

Fordy8man 10-17-2003 04:32 PM

Do you need etching primer under featherfill primer?
 
Do you need to use etching primer under featherfill primer. someone told me that i did but i thought why would i need to use a primer under a primer. if any info on this please let me know thanks. fordy8man

jwcnj45 10-17-2003 06:12 PM

Etch primer is used for corrosion protection and not as a primer/surfacer like the feather fill. It "bites" into the metal and helps primers adhere correctly. Consult the spec sheets for the feather fill. It will tell you if an etch coat primer is recommended under it.

302 Z28 10-18-2003 08:20 AM

Most paint supplier spec sheets will call for an acid wash primer for bare metal preparation prior to applying a primer/surfacer.

Vince

PrimeMover 10-20-2003 01:04 PM

I was just wondering, I know there are several ways to prep rusty areas before filler is applied. On a sandblasted surface, which is best - acid wash or etching primer, or is there much difference? I'm getting ready to work the body over on a 54 Chevy. I't has some rust issues around and under the stainless. Non of it has gone though yet, and I'd like to know the best way to stop rust dead in it's tracks, where skim-coats of plastic filler are used.

All the limited body work I've ever done, I've always applied the plastic directly to clean, dry bare metal. I never had any problems but then, I only kept those cars for 5 years average. I'd like to do the 54 as best I can.

I didn't mean to answer your question with another question, but this seemed like a good place to ask - thanks:)

jwcnj45 10-20-2003 03:37 PM

A good epoxy primer is the way to go over clean sandblasted metal in my opinion. It will eliminate the etch coat process and give you excellent long term protection of the surface. This is important if you plan on leaving the metal in primer over an extended period of time. We have used this method many times over the years in the shop where I am employed on the restorations we do and have never had a problem with it. The epoxy will not only provide protection but it will also give you high film build to help level the sandblasted panels. Etch will give protection but will have to be primered anyway thus making it at least a two step process to get the results you want.

302 Z28 10-20-2003 04:29 PM

After sandblasting the rust areas I would treat them with Ospho, or a substance like it. Then I would use the acid etch primer.

Vince

asennad 10-23-2003 03:17 PM

"After sandblasting the rust areas I would treat them with Ospho, or a substance like it. Then I would use the acid etch primer."

What's the point of that? Using the Ospho is acid etching the surface anyway so putting an etch primer on top of that is simply duplicating the etching process.

302 Z28 10-23-2003 05:27 PM

Ospho is very cheap insurance against rust getting another foothold. While the acid etching primer will help in stopping rust, it doesn't mean that you will never have a rust problem develope undr the finish.

Vince

F1 Owner 10-23-2003 10:46 PM

etching primer under featherfill
 
Hey Guys,
I've been away for awhile ,but had a chance to browse the board tonight .I happened to see this thread and had to respond .
I don't know if ospho is anything like SEM Rustmort ,but if it is ,READ THE LABEL before you use it over sandblasted metal .
Rustmort 's label states that it is NOT to be used on sandblasted metal .
Before using Featherfill READ THE LABEL ,to see if it needs an etching primer under it .In my own experience it needs SOMETHING!! . My personal preference would be PPG Epoxy Primer ,(color don't matter) rather than etch primer on bare metal .
Also ,Evercoat (company that makes featherfill) also makes a product called Slick Sand .I have to tell you that IMO this is a much better ,easier ,and versatile product to use than Featherfill , and I've used both---MANY times .Slick Sand is just as good at filling ,is used much the same way ,and has better adhesion in my opinion.Also, if you read the label on Slick Sand ,it will tell you that it is recommended to be used on bare metal ,without etch primer .Above all other advice I can give you , is READ THE LABELS on anything you use .
Hope this helps . Rick

PrimeMover 10-24-2003 08:12 PM

Thanks F1, I have to work this weekend but Monday, I'm headed out to pick up some material for the body work I need to do. I will check with 'em on Evercoat's Slick Sand. I've also used the acid etching clear liquid that you wipe onto bare metal before applying filler and had good luck with it. I think I'll pick up a little of each and toy around with it a bit.

Iv'e got all winter to iron out the body on the Delray. With Ya'll's help, I think this rookie is capable. Thanks all :)

galaxieguy3 10-27-2003 01:25 PM

Hi All,
I am not any kind of professional when it comes to any body work subject, but thought I would share some of my experience with a couple products.
I have used Rust-Mort, quite extensively actually. From my experience it does work. When I used it, I was skeptical to say the least, and after a few years, impressed. Keep in mind that it does say to leave some rust, scrape off most of it, but leave enough to chemically react. In other words do not sandblast it before applying the Rust Mort.
On the subject of covering bare metal, I am told use either self etching primer or epoxy primer. I used epoxy primer the first time around on my Galaxie. when I stripped a couple years later the epoxy primer stuck very well, actually hard to get off. This time I used self etching primer. I sprayed over some spots that needed to be filled yet just to cover it up until I could get to it. It comes off alot easier than the epoxy did.
Moral of the story is....I would use epoxy primer on bare metal even though it costs more.

troy-curt 10-28-2003 11:41 AM

I have been painting commercially for more than 40 years.
Very very rarely do I use etching primer. I use epoxy primer on every thing. and slick sand. I have never had any problems with paint coming off, or rust coming back, unless it was exposed to harsh conditions, and nothing would have helped stop that.

Good Luck
Troy

PrimeMover 10-28-2003 11:10 PM

Thanks Troy, that's good to know:)

bullheimer 10-29-2003 02:32 PM

welcome back F-1
 
so you can put the slick sand, or other bondo, right over epoxy primer just like it was any other primer? that means it's sandable right?

troy-curt 10-29-2003 08:23 PM

I never put bondo over anything.Only on bare metal.

Troy


All times are GMT -6. The time now is 07:26 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.