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Originally Posted by Ant1981
Laquer does cure.
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Ummm, sorry, it doesn't. Lacquer will NEVER cure. It will dry yes, but cure no. There is a difference between dry and cured. The reason lacquer will never cure is b/c it air dries, rather then drying chemically like a clear that uses a catalyst, such as polyurethane, urethane, polyester, etc....Some peoply say Laquer "Air Cures" which is wrong, the correct terminology is "Air Dries"
Something that is cured can NEVER be reflowed, or wetted and its solvent resistant. What I mean is this, for example, if you take an object that has been clear coated with some sort of clear that has been catalyzed with a hardener then once all the chemical interlocking has been completed then there is nothing you can do to re-wet it, or re-flow it.
However take Lacquer on the other hand, it air dries, and has no catalyst or hardeners mixed in. Therefore once it dries it can ALWAYS be re-wetted by adding heat or a solvent. Take a hair drier and buzz over a guitar that has been painted with lacquer for a few minutes and you'll see that it will start getting soft, then it will actually make a wet shiny spot in the paint, and if you touch the area it will be wet paint. Doesn't matter if the guitar has been painted for a month or 50 years, lacquer will NEVER cure b/c it has no way to. This is also why lacquer can be wiped off with lacquer thinner, b/c it has no way to ever harden. Take Urethane for example, once its cured lacquer thinner will not even faze it, b/c it is chemically locked, or cured, and cannot be reflowed or re-wetted. Also, Heat will NOT reflow or rewet Urethane (or any other catalyzed Top Coat), as a matter of fact, the hotter you get a catalyzed clear the HARDER it will get. This is why the Automotive factories "Bake" their clear, b/c it makes it A) Harder, and B) Dry faster. Catalyzed clear will cure at any temperature above 55 degrees, however for every 15 degrees you go above 68 you cut the curing time in half.
For example, if a clear takes 6-8 hours to cure at 68, then take it up to 83 degrees and your looking at 3-4, take the temp up to 98 and your looking at 1.5-2 hrs, etc.....
So, I hate to bust your bubble, but Lacquer DOES NOT cure. This is also why people who do relic paint jobs choose an air drying clear such as lacquer, and nitrocellulose, b/c when subjected to cold temperatures, then hot temperatures it cracks. Now imagine if your car did that, got cold at night, then cracked in the middle of the day when the sun got the temperature of that metal up to 150 degrees. It doesn't crack b/c its CURED.
The definition of "Cure" as found on PPG's website is.....
Cure- The chemical reaction of a coating during the drying process, leaving it insoluble.
And Catalyst-
Catalyst: Sometimes referred to as activators or hardners, catalysts contain chemicals that interact with the resins of the paint allowing it to cure. Substance whose presence increases the rate of a chemical reaction, e.g., acid catalyst added to an epoxy resin system to accelerate drying time.
Lacquer: A fast-drying usually clear coating that is highly flammable and dries by solvent evaporation only. Can be reconstituted after drying by adding solvent. Poor durability and chemical resistance are the downside.
Lacquer has no Catalyst, therefore it does NOT have the chemical reactions a paint must have in order to CURE. If you ever here ANYONE say lacquer cures they are misinformed, and misusing the word "Cure", and rather should correctly be saying "Dry" when referring to lacquer.
If you take a car that has been painted in lacquer, but it SEVERELY faded, you can make it look like a BRAND NEW paint job by simply pulling it into a paint booth, turning the heat up to about 150 degrees, it will re-wet and re-flow the paint and in 45 mins you'll have a brand new looking paint job (Minus the chips and scratches) it will be as shiny as the day it was painted, b/c the heat reflows it, b/c it isn't cured, it can't cure, it has NO WAY TO CURE, it is AIR DRIED, its no different really than spray paint, b/c spray paint IS LACQUER.
The guy who started this post asked what the most durable paint is, and catalyzed clears are BY FAR Harder, stronger, and FAR more durable than lacquer, or any other Non-Catalized clear, PERIOD.
And as far as the guy who said Urethane is only used on Cheap guitars, then you are also misinformed. Not only is Gibson now using Urethane (B/c its more durable) but PRS has been using Urethane for over 5 years ( I know this b/c I got a video with my PRS that shows how they are built and painted, and they clearly say in the video TWICE that they use URETHANE PAINT), as well as Warrior, Carvin, Fernandes, ESP, Jackson, and about 50 other guitar manufacturers. I know for a fact Gibson has started using it b/c I have a friend who paints at their Nashville Factory. Last time I checked Gibson, PRS, Warrior, and Carvin were NOT CHEAP GUITAR COMPANIES.
Ant, your talking to the wrong person about paint, I was a chemist and painting instructor for PPG Industries for over 10 years. No offense, but if you think lacquer cures you need to check again, you are wrong. Lacquer "Hardens" to some degree, and "Dries" but does not by definition "Cure" This is why Lacquer is a VERY VERY thin clear, Undurable, VERY subseptable to fading, and VERY easy to chip or scratch b/c it doesn't have a hardner (Catalyst) mixed in with it.
If this guy wants the Shiniest, Most Fade Resistant and DURABLE long lasting paint out there then a Catalyzed Clear is what he wants.
