Rules, rules, rules, so many rules. Use this don't use that. Sand this, don't sand that. These companies must think we are stupid right? They tell us to buy their products only. Of course they do, so they can make money off of us, right?
That is how many people feel. They mix and match products thinking they can out smart the chemists that created the product!
The manufacturer spent hundreds of thousands of dollars, possibly even millions, developing the product. They did EVERYTHING possible to make it perform it's best. Heck, if they found it worked better if you painted it while standing on your head, THAT would be in the tech sheet!
Did you know that most of these products you use have a lifetime warranty? That's right. The manufacturer will stand behind their primers, paints, and clears for your LIFETIME. Now, as a DIYer you can't have this warranty. What makes the difference between the warranty YOU have (usually none) and the lifetime warranty a shop may have? The training, that's what. The manufacturer has classes for the painters to go to. He then takes a test, if he passes, the manufacture knows that he understands the procedures and proper product choice. The manufacturer has learned that it is likely the painter will use the product properly and it will perform as expected. The manufacturer puts hundreds of millions of dollars on the line with this warranty. They know they can, if the product is used EXACTLY as they have instructed on the tech sheet.
I have always been the kind of guy to follow instructions. Even before I had the training I used the products exactly as I was told to. I am sure this accounts for the very few failures I have had in the 28 plus years I have been doing this work.
Five of those 28 years I was a paint rep. If there is one singular thing I came away from that job with it would be importance of following the recommendations. As a rep I visited hundreds, possibly thousands of shops. These shops were in every shape and size. From one with seven frame machines and five paint booths doing a million dollars of business a month, to a one man shop with two stalls.
Among these shops there was a very distinct pattern: the ones who went to tech school, had only ONE brand of product on the shelves, and REFERRED to the tech sheets, had fewer problems. Most of these shops had NO problems, EVER.
They were open to hear about new products and ready to learn about how to make any product or tool perform better. Oh yeah, and they made more money.
Then, there was the "dark side". These were the shops that would buy any product, any brand, just to save a dollar. Their shelves were covered with so many labels, it looked like the cans of soda and beer in a Quickie Mart cooler.
If, and I mean a BIG if, you could get them to a tech class, they were disruptive and later told me how they "could have taught that class". They were quick to tell you how smart they were and how the paint company didn't know jack about the "real world". These shops took up about 99% of my trouble shooting time. They didn't have little "how can I get this primer to dry faster?" sort of problems. They had TOTAL catastrophic failures! I was the first one they called because we must have put out a "bad batch" of product.
I tell you this only so you can understand where I get this passion that I have for using products properly. It was like watching a basketball game where one of the teams was wearing wet jeans and cowboy boots! After a while you wouldn't even have to watch, you would know what the outcome was going to be.
Most product data sheets can be read in a few minutes. They are available on line, as well as in the store where you bought the products and many are even available on "Fax Back" right over your phone.
Get proper mixing containers. Be sure the solvents used match temperatures of the booth. Double check to be sure you have ALL the components (and enough of them) BEFORE you start so you don't find yourself tempted to be "creative".
The three most important things and the most common cause of failures are as follows:
All this info is on the product data sheets, use them.
Painting can be difficult, there are things that are quite honestly out of your control. So, why not do EVERYTHING that IS in your control correctly.