What is the difference between enamel and acrylic paint?

Enamel was the original paint for modellers, acrylic being quite modern by comparison. Essentially the two paints start off the same, using the same pigment, however, enamel uses an oil-based solution mixed with the pigment to turn it into paint whilst acrylics use a water-based one. This makes the two paints behave quite differently when they are being applied and also gives them different qualities when they are dried.

Enamel has a glossier finish and is harder wearing than acrylic, often the colours appear more solid and fuller-bodied because the molecules in oils are much smaller than water so they can soak up more pigment, therefore, making it a much denser paint. Because of this enamel is very good at applying itself to surfaces and usually will not require a primer. Enamel is less likely to leave dried in brush marks as it takes between 24 and 48 hours to dry giving the paint ample time to gently settle into a smooth layer on the surface that it is applied to. Because enamel takes so long to dry, it is ideal if you want to blend colours post-application, particularly useful is you are painting camouflage or using it to weather your models, enamel can be thinned down for more transparent washes using thinners which you can also use to remove the paint once it has eventually dried should you discover a mistake.

The disadvantages of enamel are firstly, the drying times. Because it takes so long to completely dry, if you want to paint over your initial base layer with further detail or more likely apply a bordering colour, the process can become quite lengthy and will have to be done over several days as fresh paint can reactivate any enamel that has not completely cured.

Secondly, enamel is not an easy paint to deal with in the event of spillages. Just imagine if you spilt used engine oil over your favourite shirt, how difficult it would be to limit the damage. The same goes for enamel but worse, and although not difficult, you will have to clean your brushes with spirits after use.

On balance using enamel is not a quick option, but will give a professional and satisfying finish to your model if done correctly.

Acrylic paints are fast becoming the most popular paints for modellers. The main advantage is the super-fast drying times, often in as little as 15 minutes. There are more colours and shades to choose from compared to enamel paints and if you can’t find the colour you want, then acrylics are very easy to mix. Being water-based, thinning the paint down could not be easier, just add more water! And in the event of spillages, the paint can be easily washed out which also makes brush cleaning at the end of a modelling session as easy as washing a dinner plate. Acrylics are non-toxic and do not need half a day of shaking and stirring before use, unlike their enamel counterparts.

The disadvantages are: once acrylic is dry it is much harder to remove, often a good sanding down or re-paint is the only option to rectify any mistakes, it can be harder to get a good coverage to your model because it is a less dense paint and several coats may well be needed, sometimes an undercoat of primer will be required too. Because of the uber-fast drying times, the paint can often lock in brush marks so the finish might not be as smooth as you would like, also the finished paintwork is not likely to be as hard-wearing as enamel.

Enamel and acrylic paints can be used together if you wanted to. For example,  paint your engine in an enamel, then use acrylic for the weathering. In this instance you would be using the best paint for each job, the critical point here would be to make sure that the enamel was completely dry before applying the acrylic. Don’t forget it takes two days for enamel to completely dry!