I recently picked up a hood at a swap meet that needed to be stripped before a repaint.
My question is this...
Once the hood is stripped, can I use some store bought rattle can enamel primer to block the hood and then use the professional primer over top, or will the enamel cause problems down the road?

 

How bad is the hood?
If its still got paint and isn't blistering to bare metal,I think ya should be able to just sand/prime when you're ready to paint the rest of the car.

 

it had a bad repaint in the past and the paint is flaking off in chunks

 

it could cause problems if you use rattle can stuff under something like that. not that it for sure will but it a very real possibility that it could. i personally wouldnt trust it on something as big as a hood. if you had sanded through a little spot and wanted to put a lil down i might would give it a shot.

 

DO NOT Use ANY kind of rattlecan anything on your car, if you want to keep it and keep it nice....!!!

 

Diffinantly what he said!

 

Why exactly?
I have used the rattle can SEM stuff on my bumper covers and also used some rustoleum stuff on small things like filling small holes for a gfx swap.


I have had no problems with either.
Now,I wouldn't recomend painting an entire car,hood or any panel solely with a rattle can but they do work well on some stuff.

 

i am not disagreeing or agreeing but with a bold responce like that you do have to give some kind of explenation!!

 

sorry kevin g but im gonna have to disagree with u for this one. upol i think is how you spell it, anyway that make some pretty good etching primer and high build primer. like i said i wouldnt use it on a big job but a small spot doesnt hurt. ive done it many times. not that it means much but its not the kinda stuff you gonna get from autozone or something, it comes from the paint store where we get our other supplies from.

 

First of all, rattlecan stuff available over the counter is garbage. It is "highly refined dirt" SEM's is a better refined product, and I have used much of it...It is still a 1K product, non-catalyzed.
I will backpeddle here a bit an partially agree with 89inporteater....BUT, and we are talking about a BIG BUT!!! The proffessional grade rattlecan stuff is not EASILY AVAILABLE over the counter...Etch primers and the like. (you will also notice here that the rattlecan etch's are for spot work only etc..roughly the size of a quarter or so...ie; if you have a breakthroug after final prime...)
I do know SOME high build primers available in a rattle can and even a roller set up...BUT MOST ARE IR cure only!!!
BUT we are moving off topic!!! The O/P stated that he was going to strip the whole hood and prime with a rattlecan...
not a good Idea.

 

agreed kevin g, u still da man

 

Not everyone has a bunch of money to get a full repaint for a few bad spots. My car had a BUNCH of rust spots. I fixed them with my sander and some RATTLECANS. It cured the problem...

 

What SEM products have you used?

 

also,UMMMM!
If its a 1k,isn't that what a rattle can is suppose to be?

 

hey guys, i really appreciate the info!!!

just remember, play nice, we are all friends here

 

I tend to agree that, at least in this instance, you should stay away from the rattle can stuff. When you say you intend to use it to "block the hood", do you mean use enamel to protect the bare metal from the elements until you can apply the "professional primer" over it ? If so, why not wait until you have that primer available before stripping the existing paint (however bad it may be), and thus eliminate the enamel altogether? The hood has had that paint on it for a long time, I'm sure. It can stay there a little longer.

The reason why rattle can may not be the best choice here is this: most professional primers today are catalyzed, meaning that a catalyst is added before spraying the material --but after you pour it out of the can-- in order to make it cure, or harden. Spray can enamel, on the other hand, is uncatalyzed. Otherwise, it would harden inside the can, making it impossible to spray. The trade off is that the stuff never fully cures. This explains why the enamel paint on older cars is oxydized. The solvents in the enamel keep evaporating for as long as it is exposed to the environment; they work their way through the shiny top coat, which causes it to dull and eventually peel off.

The situation is a little bit different in your case, in that the enamel would not be the top coat. However, the primer which you eventually will spray on top of the enamel has its own solvents. These will react with the enamel below, with the result that over time the reaction will find its way to the topcoat, causing it to wrinkle or crack, or do a number of other weird things, none of which are pretty.

If there was no enamel for the primer to react with, the primer would cure as it is supposed to, and the topcoat would not "move" over the life of the car.

You could sometimes get away with spraying a small spot because it would be less noticeable in the first place, and also because you would have minimum build with enamel in a small spot. On an area as large as a hood though, there are just too many things that could go wrong eventually. So if you plan on using anything "professional" at any one point, I think you should keep the entire process professional.