Srt-68 Barracuda

Going the poly primer as well. So awesome fills the 80 grit scratches and sands really easy. I love the stuff makes life so much easier.

Just heard more bad than good about etch these days from a paint chemist. His email "Acid etch is a non catalyzed product and is nothing more than a lacquer product with the reducer containing a small amount of acid for etching.

The above statement should say it all but if it does not here are the potential problems.

It is very easy for the acid to get trapped either in metal pits or where ever there is an over lap as this product is not made to fill or be applied thick. Any time you have acid that traps or does not dry you will have loss of adhesion.

Next problem and a more serious problem is, if you spray a panel and let it set for a week or a year you can take a good grade lacquer thinner and wipe it off as like lacquer it never dries.
Now if thinner will wipe it off, what will urethane reducers do to it?

In the past what has happened is someone will spray 2K primer over the acid etch and any spot that gets too wet the urethane reducers in the 2K will melt those spots.
You will not know it as the primer will dry just fine.
However now you have air and solvent from the melted acid etch setting against the metal and it will start the rusting process. As the rusting process starts forming a gas you will see baby pinhead bubbles show up and as it gets worse bubbles the size of dimes can appear.
I have seen bubbles show up a week after the car was painted and I have seen them show up years down the road.

It’s the same risk as using lacquer primer, the car may show problems right away or it may be fine for years. You just don’t know.

In today’s market, most restorers or Rod builders do not use it as they have all been burnt
In the past. Where it is used today is in high volume collision shops as they cannot afford to wait an hour for epoxy to dry and the acid etch is ready to prime in around five minutes. It’s a pretty safe bet as most of these type repairs the customer is not going to keep the car longer than another 2-3 years.

How to tell if it’s acid etch causing the problem:
Take a razor blade and cut the top of the bubble, you will see rusty solvent and if you blow on it, it will go to bare rusty metal."

Food for thought