temporary primer

[bkelly]

Does anybody make a temporary primer? I've started removing the paint from the body/panels....so far no metal work needs to be done! It won't be going into paint until at least next summer/fall so something needs to be put on it to prevent surface rust. I'm not too familiar with auto body products so I have no idea what's out there.

[Exdamyankee]

No need for a "temporary" primer. If it were easy to remove, it would be a lousy protectant for the metal. Just spray it now with a decent automotive primer now and just scuff it up when you are ready to paint next season. You can always prime & paint over the old primer.

Are you going down to bare metal? If so, use an "etching primer" that bonds to the steel. Then spray a regualr automotive primer over that. If you are not going to metal, you can skip the etching primer.

[bkelly]

It's going down to the metal so I'd be using the etch primer. I was wondering when I got to the point where I was using filler, if it should go under or above the primer. The filler that's in the car now was under the primer. It looks like there is two kinds- a blueish gray that is in the dents and a tan that's leveling everything out. The blue is much harder than the tan. Other than that, what's the difference?

[EScanlon]

ALL primers are prorous and won't protect the metal for that long a period of time. You would actually be better off using Rust-o-leum or some other "all-in-one" product and then sanding it off down to the metal next summer. Don't be fooled by the "skin" the primer gets after being sprayed, it will NOT prevent water from seeping through. This goes for Epoxy, Filler, and Sealer primers. All of those should be top-coated with paint.

Do not forget to sand off the Rustoleum when you continue the project, it's not compatible with most top-coats and WILL require the use of a Sealer over it.

The theme of over or under the primer is a subject of a lot of debate.

Your best bet is to spray an epoxy self-etching primer and then apply the bondo or at least use a metal prep solution to etch the metal and then apply the bondo and then top with a filler primer. There are a lot of opinions on this subject alone.

The "blue" primer you're referring to may be one of the epoxy primers, while the "tan" is more than likely a filler primer or a sealer. I put the colors in quotes because one person's blue is another's off-green. My filler primer when first put on looks "mauve" (yuck!) but then eventually cures to a pale "beige/brown/tan" and sands pale gray....go figure.

FWIW

E

[LanceM]

Epoxy primer is the only way to go, but you will need a spray gun to put it on it's not available in a rattle can. As stated above regular primer isn't going to protect the metal.

[geezer]

That is a common problem we all have to deal with. The metal must be protected from corrosion during the restoration process. Most of us doing this as a hobby don't complete all the metal work in one quick session. It is done in stages and we don't want the areas already repaired rusting away while we are working on another area. What Enrique has said about the porousity of primers is very true, but there are epoxy products designed for just this purpose. I wouldn't recommend leaving metal coated with only this out in the elements (example-driving project car), but it will seal out the moisture and protect the metal better than any other option available, until you are ready to paint the topcoat. When you are ready to paint, you just clean/degrease and lightly sand. It has excellent adhesion properties. That word adhesion is the key word for your other question also. I have seen excellent results with fillers being used under or on primers. It's all in the prep work. If the metal is properly etched, chemicaly or mechanicaly and cleaned, adhesion is not a problem. Anyhow although not cheap, this is my recommendation for a longer term restoration project that is not exposed to the elements. If anyone can't find more information on the web for this, I will post the other 3 sheets of information they give you when you buy it.

[EScanlon]

One note about the Epoxy Primers, even they will not protect you for a long time, and a year + may be pushing it to the extreme limits.

Most, if not all, recommend that they be topcoated for full protection and within a period of time after they've been applied. Otherwise, you need to sand /scuff the "skin" off the primer to promote adhesion of the next coat of paint or primer. It won't adhere properly otherwise and you'll literally peel it off.

The epoxy will seal a lot of materials, and that is one of it's uses as a Sealer, and it will even skin up such that it will provide a layer of moisture protection...but only for a short while. I had that happen with a 76 Mercury Capri II. I applied Epoxy over my bodywork/sheet metal while I got the rest of the car finished, and within 6 months had rust showing through the primer. It was my daily driver, and winter, so undoubtedly that had a LOT to do with the primer failing to keep it protected.

But the key point here is that you're looking to protect the metal for an extended period of time....at the lowest cost possible....while you do bodywork in stages. That is why I recommended Rustoleum, Krylon, or some other METAL paint in a can. You'll find that many of those types, while they recommend the use of primer, can and often are, shot directly onto bare metal. You'll need to remove it when you get back to completing the project as most are incompatible with automotive finishes and even the sealers can have problems with them.

2¢

E

[geezer]

Enrique - What you say is true. This particular product I've recommended does have to be sanded to ensure adhesion after it has fully cured. But I find that to be much faster and covenient than removing a coat of Rustoleum. Because my garage is climate controled I can't say with any degree of accuracy how long someone else could wait before topcoating and I've never waited more than a year, but I'm sure I could. Only downside for me is the cost, OUCH!! Good paint prep does not come cheap.

[EScanlon]

Ron;

Here's where discussing two sides of the same coin can cause confusion even amongst those discussing it.

While you are perfectly correct in the ease of sanding later and then applying your top coat, I was addressing the need to keep the metal from corroding beneath the primer.

In my experience with PPG's Epoxy (remember the Parrot Sh*t green primer?) although it is an excellent primer for bare metal with only a minimum of surface preparation (it self-etches and is a great sealer for other compounds) it is still somewhat porous once the skin has been scuffed or even after it has aged a bit in the sun. That's where the problem lies. The non-porous skin is only good for a few weeks...unless kept in a garage and out of the elements and sun.

If BKelly just uses the Epoxy primer as his one and only line of defense against corrosion, he'll have no choice but to leave the car in a garage or possibly face corrosion on the sheet metal THROUGH the epoxy primer.

The one-step paints (Rustoleum, Krylon et al.) while a total PITA to remove later (and you MUST in order to topcoat with something else), at least do skin over well enough to protect the metal from corrosion.

Heck, if BKelly were to apply ANY kind of metal primer and then top coat it with ANY kind of paint (except household or latex), he'd get the protection he needs...except at twice the cost. He would STILL have to sand it down later, but only as far as the primer (although in my book he should do Epoxy as a base primer and not a fill primer).

Your receipt mirrors the ones I have for the Roadster I just finished painting. It's funny how people think that "it's just paint" comes cheap.

FWIW

E

[zbane]

This is an interesting topic.

I looked around at various websites and found that this product looks pretty promising.

Fluid Film

Below is a link to the frequently asked questions page.

http://www.eurekafluidfilm.com/globals/faq.html

[geezer]

Enrique - I can tell you this much. Most people will stick with the same game plan if it has worked well for them in the past. That's the way I am. That is not to say there are not other methods that will net great results also. I used to have lunch with a PPG rep at least once a month before I retired, and although we mostly discussed paint systems for industry, I did get the heads up on new products I could use for my projects and this line of epoxy primer was one I was immediately sold on. Whether or not it suits your needs or BKelly's, I don't know, but it is worth a look if it does. At the risk of expressing myself any more clearly than I can think I'll leave it there. I'm sure we could discuss this for hours.

[bkelly]

I've decided to prime first then do the bondo after the metal work is done. The bottoms of the fenders have a couple rust holes that need to be cut out. After they are primed, the panels will be stored in my house. Metal work will be done next year. It just snowed so my days of working on this car are numbered. (One car garage with no light or heat) Worst case scenario is I have to sand down and reprime the body next year. No big deal.

As for the primer, should I use Epoxy or Etch? Or are they the same.....