Beginners Guide to Painting Diecast

A Diecast Lab Guide

Painting diecast can be a model builder’s nemesis or friend. This guide will help you understand paint and how to get great results. The first step to painting is to consider your space. Many enthusiasts work in a space that is not viable for an airbrush or stationary paint booth. It may be, we are limited to using aerosol paints. 

Level 1

I have painted really cool models using nothing more than aerosol paint and stepping outside to shoot (even on really cold days), then letting part dry in my house. There is an old photo somewhere of model parts hanging all over our kitchen to dry. 

To paint diecast, the most common way to paint is aerosol. It is simple, stores easy, and economical. One thing to keep in mind with aerosol is you get what you pay for. 

Krylon, Rustoleum and other discount store paints work fine, but I have had more trouble with these paints not behaving. What do I mean by not behaving? With lower quality paint I have had trouble with the paint “cracking” with the second and third coats of paint or even when the clear coat is applied. 

What happens is the second coat is applied and the paint and or primer do not interact well. There is a chemical interaction that causes one of the layers of paint to crack or wrinkle. Basically it means we strip it down and start over. 

One key to using lower end paint, keep the brand consistent. If using Krylon primer, use Krylon color and clear. That seems to prevent some of the common problems I have had using this kind of paint. 

The lower end paints can give great results and I still use it for some applications. However, when I have had trouble, it was using lower quality paint. 

Level 2

We can upgrade paint quality by using Tamia, Model Masters, Testors  and DupliColor or other automotive grade paints. The first three brands are found in hobby shops and come in small quantities for our purpose. These are much nicer paints and can provide better results. 

Duplicolor paint can be found in automotive stores in vehicle colors and basic colors of red, white, black, blue etc. This paint is higher quality and goes on very nice. 

I have discovered we can use a lower grade primer with these brands on top and get great results. Each of these brands has their own primer that is compatible as well. 

Another way to get specific colors of paint is to have a company custom mix paint matched to a VIN or specific paint code. These paints can be mixed and put in an aerosol can for the reasons described above. 

I have bought many cans of paint just like this matched the VIN of semi trucks. One thing nice about this kind of paint is I rarely, if ever, have any trouble with this quality of paint. The few times I have had trouble is when the painting process is rushed or the conditions for painting were not ideal such as high humidity or the temperature of the paint or workspace was too cool. 

Level 3

Custom mixed paint I mentioned in Level 2 can be bought in small quantities we can spray through an airbrush. Testors and Tamyia both offer small quantities of paint as well. These paints have to be applied with an airbrush or regular paint brush. 

The airbrush is a game changer as we can apply paint precisely and in very thin layers. With aerosol we are at the mercy of the nozzle and the mixture in the can. Some aerosols come out thin and others thick requiring us to adjust as we spray. Even the Level 2 quality of paints can vary on occasion depending on the color. 

Going to Level 3 paining does have downsides. First, there is the cost of the airbrush which requires an air compressor to function. Costs of these pieces can be $50 on the low end to $300. Then we have to purchase an air compressor which can be $70 to $250 depending on the accessories purchased with it. 

Then we have to learn how to use the airbrush which can vary depending on how fast we might catch on. And finally, set and clean up takes longer than shaking up a rattle can. 

With that said, the results are impressive with airbrush.  

I am using a Iwata Revolution gravity fed airbrush. Check out my affiliate link

Rather than use a traditional airbrush compressor, I am using a California Air compressor for its multiple uses and the #1 reason I love this compressor, it us SUPER quite. See it here.

Prep and paint basic.

For a complete strip and repaint of a diecast model, here are the basics of prep to clear coat

1. Strip the diecast of all paint (see the video here)
2. Once the paint is gone from the model, dip in rubbing alcohol to remove any fingerprints, oils or other contaminants that can interact with the primer. (rubber gloves are recommended to keep contaminants off the diecast)
3. Ideal painting temperature is +65 degrees F. Painting can happen at lower temperatures, make sure the drying space is 65 degrees or better.
4. When possible, warming up the paint and part helps the paint/primer adhere to the part. Be careful to avoid overheating the aerosol paints to prevent the can from bursting.
5. Wait until parts are touch dry before adding more coats. The longer the parts have to cure will ensure the second coats go on without flaws. Twenty four hours between coats would not be outrageous.
6. When applying decals, apply a clear coat over the decal to ensure the decal can not come off.
7. Molotow Chrome – Molotow Chrome pens are relatively new to the market and are amazing. They look like real chrome! Key message on Molotow, DO NOT apply the chrome then clear unless the chrome has had several days to cure. Clear coat will dull the Chrome and make it look more like aluminum paint. The work around: 
   1. Wait several days for Molotow to cure well then apply clear 
   2. Apply a clear coat, then, Chrome. (My preferred practice)