Body and prep work:

[Captain D]

I wanted to see if I may ask a question about something being done on my Charger if I may please.

Before my car went to the body shop to have the quarters done, my Charger was taken down to the bare metal and treated w/ an Etching primer. The body-man did a good job w/ the quarters, but sanded down the etching primer, did mud work w/short-strand fiberglass along the new quarters, and then applied epoxy primer over top of everything that was done.

My question is...was the body-man correct is what he did to prevent rust? I just would hate the thought of this thing getting all of this work and find out only later down the road that we did not do what was needed to correctly prevent rust. The car looks really good, but it was not what I had expected for him to do (apply mud work "THEN" apply an epoxy primer).

So, based on what he had done and what he was telling us...In your opinion, it is safe to have etching primer + mud-work "UNDER" the epoxy primer? I'm "assuming" that its okay, as long as the mud-work and etching primer is simply sanded down real good before the epoxy...

Some excellent and very knowledable members here had mentioned that it may be best to apply epoxy first, then do mud work/bondo, and then hit it again w/ an epoxy primer. But, I'm just curious to write and see how many here have actually went this route w/ their cars and how your cars are holding up more or less over the years? I should note that this car will never see rain, sleet, salt on the roads, snow, etc. in its retirement years.

Thank you for your time, help, and clarification,
Aaron

[375instroke]

I think etch primer is the quick way to go, but not necessarily a bad way.  I like the liquid metal cleaners and conditioners, then epoxy.  You need to know what products are being used.  PPG, for instance, has some etch primers that are compatible with their epoxy primer, and some etch that isn't.  Evercoat makes very good fillers.  They recommend their fillers on bare metal, and they say that their products have excellent corrosion prevention properties.  What specific products are being used?  PPG, on the other hand, says their fillers may be used on bare metal, or epoxy.

[Troy]

He sanded the etch primer off or just scuffed it? Many times etch primer is applied temporarily to keep the bare metal and welds from rusting until all the metal work is finished.

There are endless threads across the internet debating the proper order in which to apply things. Overall, I think the general consensus is that most of these cars will live much more pampered lives than they did the first 40 years so anything that provides a good seal will likely outlast the owner.

My personal opinion is that etching primer AND epoxy is a waste. Etch primer should not be applied over filler - only to bare metal. Epoxy adheres very well to metal and was also what the factory applied. It lasted this long.

Troy

[Captain D]

Thank you gents for the replies,

You're exactly right that the etch primer was applied to prevent the bare metal from rusting til' further progress could be made. I was away at college while a majority of this work was being done, however, he took several pics of the progress of each stage in order for me to view the steps.

Upon examining the pics, I can easily tell that the etch primer (not an expensive brand) was sanded down and scuffed pretty good before the filler was applied. Although its unable to tell w/ 100% certainty that there was much etching primer left between the filler and bare metal, it is obvious from the pics that it was indeed sanded very thoroughly. Over top of that, it looks as if he put some form of white filler over top of the regular filler before the epoxy. And, I can see also various small bare spots that would ultimately be hit w/ the epoxy.

His goal, he said, was to do this and then keep re-applying w/ coats of epoxy, then add filler if need be, re-epoxy w/ another coat til' its straight. I realize that pictures say a thousand words so that if it helps, I can see about posting some pics. I'm not the greatest at that, but I can try..

I asked him to epoxy prime "before" any mud-work went onto the car and he disregarded that request by stating that filler work adheres best on bare metal and once it is applied, then the primers are used, such as etching, epoxy, and filler primers. Is he correct?  Overall, is this something that I should be concerned about, specifically regarding rust-issues later on down the road?

Thank you again for your time,
Aaron

[TylerCharger69]

Actually....the etching primer is a good cover in order to keep the metal protected.  Now applying fillers....it's best to apply on to bare metal... once the body work is done and the high build scratch filling primer is finished, it's a good idea to spray sealer over the entire car....or the entire panel....depending on what your working on.   But as far as sanding the etching primer off to apply materials.....no...it won't hurt  as long as the car is sealed before it can get contaminated.

[Charger-Bodie]

Actually....the etching primer is a good cover in order to keep the metal protected.  Now applying fillers....it's best to apply on to bare metal... once the body work is done and the high build scratch filling primer is finished, it's a good idea to spray sealer over the entire car....or the entire panel....depending on what your working on.   But as far as sanding the etching primer off to apply materials.....no...it won't hurt  as long as the car is sealed before it can get contaminated.

Etch primer is for use under non epoxy sealers and primers that don't have there own corrosion resitance.

Epoxy primer sealer is for sanded clean bare metal. IMO is is the best thing to apply to the bare metal. It seals off any tiny pinholes ,etc. that may be in a weld etc. Epoxy seals off the bare metal better than anything else . period. It however will not adhere well to self etch.....Use one or the other. And also do not use filler over or under filler of any ind...it wont stick.

As far as the filler sticking to bare steel. This is the only argument there is for the filler directly onto steel . But lets face it if you get hit in filler its most likely gonna crack either way. Filler sticks great to properly prepared epoxy. and the metal under the filler  work is sealed that way....

[Captain D]

Thank you again gents for the reply,  Two more general questions:

1.) With regards to filler primer in general (such as Duplicolor), is it to be used only "after" the epoxy primer is applied and sanded smooth? In other words, its the last and final primer to be used (and wet sanded) on the car just prior to the actual paint job if there are minor scratches present from when the epoxy was sanded?

2.) When we were changing body shops, we had a few areas that had some filler work done, however, it was not sanded down and treated just yet. However, we got caught in a brief shower in transit. Since I read somewhere that filler (bondo) holds in moisture, do you feel that it may be a good idea for me to sand down those areas and start over where the filler-work was exposed to the weather "before" we proceed further on the primers, etc.?

Thank you again for your guidance,
Aaron