About Hobby Paint
This exhaustive hobby paint guide is intended for plastic modelers. All of the terminology and techniques here will be catered to that hobby, and this working knowledge has been compiled by me, Liam's Hobby Room, based on what I have found to be true over 15 years of plastic modeling.
Here, I will teach you about all the different types of hobby paint, how to thin them, how to work with them, which ones are compatible, and what to expect.
What You'll Learn In This Guide
Hobby paints, like those from Tamiya and Vallejo, are formulated for precision and fine detail, using finely ground pigments for smooth application and vibrant colours. They are designed for scale models and figures, offering quick drying times and airbrush compatibility. In contrast, craft and canvas paints are more general-purpose, with coarser pigments and higher filler content, resulting in a thicker consistency and less vibrant colours. While craft paints are versatile for various surfaces, they lack the fine detail and smooth finish required for detailed hobby work.
In short, craft/canvas paints are made for application to porous surfaces (like canvas and wood) and hobby paints are made for application to non-porous surfaces (like plastic and metal.) This doesn't mean one is necessarily "better" than the other (that depends on individual manufacturing quality), it only means that it each type is suitable to a different surface.
Solvent VS Base
The building blocks of paints determine their mixing and usage.
In the context of this guide, a solvent is the substance which dilutes the paint, while a base is an additive component within the paint mixture. For example, many paints are water-based, but that doesn't always mean they are water-soluble. This terminology can be confusing for beginners and seasoned pros alike based on how often they are misconstrued. Some water-based paints use alcohol as a solvent (Tamiya Acrylics), and some use a water-soluble acrylic resin (Vallejo Model Color). This guide will tell you which is which, the properties of each, and how to work with them for the best results.
In most cases, it is the solvent that dictates whether or not paints can be mixed together. As a general rule, paints using different solvents do not mix. For example, water-soluble paints do not mix with alcohol-soluble paints, despite both of them being labeled as acrylic paint or water-based.
Some solvents are stronger than others, and may not play well together. From weakest to strongest, they are water < enamel < alcohol < lacquer. Never apply a stronger solvent over a weaker solvent, as it may eat the layer beneath it. However, you can apply a weaker solvent on top of a stronger solvent so long as the base layer is dry. For the performance of different types of paint, continue reading.
To strip cured paint from a model, you can soak it overnight in a plastic tub filled with industrial degreaser. Keep in mind this method may weaken or dissolve putty, glues and cement.
Thinning Your Paint
It is crucial to thin your paint with the correct thinner.
Unless otherwise specified, all hobby paint requires some level of thinning. The ratio for each type of paint is different, but one metric is the same: thin your paint to the consistency of skim milk.
It sounds silly and hard to measure, but this is the best way to ensure your paint performs properly and reliably. This is true for painting by hand or with an airbrush (though for the latter there are additional thinning strategies). Ensure your thinner matches the solvent type of your paint.
For ease of use, purchase the dedicated thinner made by the same manufacturer as your paint. That way, you can be sure it will be compatible.
What Thinner to Use?
Water-soluble paint uses water (tap or distilled depending on water quality) or water-based acrylic thinners.
Alcohol-soluble paint uses isopropyl alcohol thinners.
Enamel-soluble paint uses white spirits or enamel thinner.
Lacquer-soluble paint uses lacquer thinner.
Specialized Mediums
Some water-soluble paint lines include a flow improver intended for airbrushing. This is not a paint thinner. It is the paint carrier without pigment, intended to prevent the pigment from clogging inside your airbrush. It is exclusive to water-soluble paints due to their extremely fast drying time.
Paint retarder is a chemical that slows the drying time of your paint. What this does is allow more time for your coat of paint to level out, smoothing itself over time before drying. This creates a glossier finish.
Certain manufacturers may offer a rapid thinner or accelerator, which is the opposite of a paint retarder. It speeds up the drying time without giving your paint much time to level out. This results in a matte finish.
Liam's Hobby Room
Artist/Hobbyist/Performer from Victoria BC
Liam is a firm believer in setting oneself up for success, and that having the right supplies for any job is the best way to start one. Never happy with purely anecdotal knowledge, participating in the hobby has proved the only way to see progress. Liam has spent his hobby years making mistakes and learning from them by pushing himself to try new techniques, and consolidating his knowledge base of tools and supplies.
While he certainly doesn't claim to be a master or anything, it is the intention that this guide be used as a reference by both new and seasoned modelers alike so that they can have more fun with their hobby and get better results.