What is the difference in paint? 1k or 2k Enamel, acrylic Enamel, Acrylic Urethane, Polyurethane and base coat clear coat Picking the right paint for your vehicle can be confusing and going to the paint store and asking this question can be embarrassing at times to say the least. So here is a quick paint reference for you to decide what type paint fits your preference, budget and skill level. **Note this is not about water-based paint nor lacquer – just solvent that’s easy to buy just about anywhere!!! What is 1k and 2k? 1k comes from the term Komponent (i.e. component). 1k means simply just the paint is required to dry. 2k means an activator or hardener is required to dry/cure. What types of paint are 1k? Lacquer, Enamel, Acrylic Enamel and Base Coat What types of paint are 2k? Acrylic Urethane, Polyurethane, Clear coat What types of paint have an option for a hardener? Every type has an option – however some brands the way they are made – a hardener is not compatible. Look at the data sheet for instructions to see if a hardener can be used. What does a hardener/activator do? A hardener crosslinks or bonds the coating to a denser/harder film. This gives durability, chemical resistance and color holdout. Enamels: There are 3 types of Enamels – Short Oil, Medium Oil and Long Oil Enamel. Long oil is what you see in tractor supply stores, home improvement stores etc. They are super easy to get a shine, but have no color holdout. The product fades very quick and chemical resistance is very low. Long oil takes a long time to dry, and can even get retack (gets sticky in direct sunlight). Long Oil in direct sun has a Gloss life from about 6 months - 2 years. Repair-ability is very difficult. The paint rolls instead of powder when trying to sand, when painting on top of it, very high possibility of wrinkles. Usually stripping is the best method of repairing, but with a very low cost – sometimes this is a consideration. Price ranges from about $22-$38/gallon Medium Oil is what a lot of heavy equipment is sprayed with. It’s very easy to spray, dries faster than a long oil (but still a slow dry product), a little more durable and only goes through a few retacks. Medium Oil is more solvent resistant and last double the life span of a long oil enamel. MOE in direct sun has a Gloss life from about 1.5-3 years. Repair ability is difficult without an activator. Paint will roll up when sanding and has a very high possibility of wrinkles when using an automotive paint. Usually best to repaint with the same product. Can use VM and P Naphtha to reduce in a lot of moe type paint, which is not a harsh solvent and has less of a possibility to wrinkle. While not as inexpensive as a Long Oil enamel, MOE is still an economical choice from prices ranging from $35-$75 gallon. These can be purchased from specialty industrial store. Short Oil is what most all car enamels are. It has a quick dry time, hardly noticeable retack, fast dry times, more durable than long oil and easy to apply. Metallics can be a challenge due to the faster dry times. Short Oil in direct sun has a gloss life from about 1.5-6 years. Short Oil enamels are still inexpensive depending on brand. Prices range from $65-$150 gallon. Acrylic Enamel Acrylic Enamels are built into Short oil enamels. Acrylic is added to make acrylic Enamel. Acrylic adds durability, quicker cure times, and great repair ability. Acrylic is soft in nature and makes buffing a lot easier. Acrylic Enamel works best activated. A/E in direct sun has a gloss life from about 2-6 years. Has little to no “retack”. Skill level is a little more advanced due to adding an activator, but should be considered. Prices for A/E are the same as a Short Oil Enamel but you have to consider the activator. Price range $65-$150 gallon plus half pint of activator (in most cases) costing from $10-$25 Acrylic Urethane Acrylic Urethane is the standard in the automotive repair industry. It’s the most used due to its great color holdout, excellent repair ability, ease of buffing, good chemical resistance, fast cure times and great flexibility. Clear coats are in most cases Acrylic Urethane and a lot of single stage paints are acrylic urethane. Metallics can be difficult to spray with acrylic urethane. Skill level to spray is more advanced, not as easy to slick out, can orange peel and run/sag. Must use an activator to cure the product. A/U is soft and can scratch with minimal effort, but can be repaired by buffing in most cases if not too deep. Pricing for Acrylic Urethanes are higher than Enamel mainly due to more activator having to be used to crosslink the product. Usually the mixing ratios for Acrylic Urethanes are 4:1 or 2:1. Cost can range from $80-$700 gallon plus activator ranging from $35-$150 quart depending on brand. Durability 4-7 years. Polyurethane Polyurethane is mainly used in fleet applications where strength and durability are demanded. Polyurethane is the most chemical resistant of any of the above topcoats. It has excellent flexibility, color hold out and scratch resistance. The one downside to Polyurethane is, because it gets so hard, sanding and buffing is nearly impossible after full cure. It’s also slower to dry than acrylic urethane. Polyurethane is a great choice for chassis, under hood, race cars, fuel tanks, engine blocks, big trucks, boats etc. Metallics are difficult to spray in Polyurethane as well. Polyurethane cost about the same as Acrylic Urethanes and mix ratios usually are 3:1. So some shops order 3 quarts of color and 1 quart of activator. Durability 5-10 years. Base Coat Base coat can be made out of acrylic, polyester and vinyl. Base coat is an excellent choice for metallic colors. Metallic single stage cannot be buffed properly because you actually scratch the flake itself and hard to polish correctly. With base coat you can spray, lightly sand trash out, rebase then after everything looks correct, apply a clear coat. Base coat is very easy to apply, however clear coat, after the 1st coat, can be difficult because it’s hard to see what you are painting. Doing a period correct restoration (pre 80’s) – base/clear is usually not the right choice due to its gloss level. However you can get most any color in basecoat. Base/clear is easy to repair (same as acrylic urethane) however some basecoats if you sand through the clear, will lift and wrinkle and become very difficult to repair. Durability is 3-10 years clear coated and 1 year without clear. Base coat has to be reduced with solvent, usually 1:1 or 2:1, so 2 quarts can get you a gallon sprayable. Prices range from $120-$1200/gallon Hope this helps with choosing what paint to use with your next project. Please note this is just an overall review of types of paint, and while your enamel might have lasted 20 years, there are a lot of things to consider shade, wax, dirt/grime etc. Also application plays a huge roll in durability. While clear coat might peel off a new car in 2 years, with proper application it can last 20 plus years as well. The durability is based off of no maintenance in direct sun. I have seen Enamel and lacquer paint jobs that are well over 30 years old, and don’t want to have a debate about durability. This information is based on real testing in worse case situation. The durability is lost when the coating starts to fade. Sometimes to go from fading to cracking can take 10 plus years. There are also junk brands of product out there, resin, pigment and the way the product is developed can all change the durability of the product. Hope this helps.