Why Should I Sand and Prime my Cooler?

We get this question all the time because let's face it, sanding and priming your cooler is THE WORST part of the cooler painting process! Picking out designs and painting your cooler are super fun and creative, but getting your cooler ready to paint is a HUGE pain. This is why we started SratStar. We wanted to provide an option to paint a frat cooler without all the hassle, expensive, and mess that it takes to convert a store bought cooler into a ready to paint cooler. 

Since sanding and priming is such a huge pain, people often wonder if they can just skip the process all together and go straight to painting, but we are here to tell you that this is a bad idea and here is why!


Why Should I Sand My Cooler Before Painting?

Remove Mold Agents

Making plastic parts is a lot like baking muffins. The first step in baking muffins is to put in non stick oil in the muffin tin, so that you can remove the muffins from the tin when they are done baking. If you have ever forgotten non stick spray when baking, you know that getting the muffins out of a tin that has not been sprayed in impossible without damaging the muffin.This is also true for plastic parts and coolers. The manufacturer will put a "non stick spray" into the mold to make removing the parts after they are done cooling easier! This non stick spray is essentially an oil. Now, Imagine trying to paint over an oily surface...obviously your paint will not stick to this surface at all. This is essentially what you do when you do not sand your plastic cooler. You are hoping paint will stick to oil, which we know, just won't happen. 

mold agent why sand frat cooler 

Create a Micro-Texture in the Plastic

Let's say that you use a chemical solvent to remove the mold agent from the plastic. You may be asking, since I removed the oil, can I start painting now? The answer is still no. Removing the mold agent is just the first benefit of sanding. The second and a crucial reason to sand your frat cooler is to create a micro-texture in the plastic. The micro texture of a molded part is very smooth. Even if the plastic has a visible texture, the micro texture is still smooth. Sanding your cooler with a fine grit sand paper introduces tiny scratches into the surface of the plastic. These tiny scratches allow the primer to grab onto the edges of these scratches and are ultimately what keeps your paint on the cooler.

Micro texture why sand a frat cooler 


Remove Unwanted Aggressive Texture

Sometimes store bought coolers will have a texture that is difficult or impossible to paint. Along with the benefits mentioned above, sometimes, you will need to sand down these aggressive textures in order to create a smooth paintable surface! The trouble with sanding down an aggressive texture is that while sanding, you are thinning the plastic cooler in that area and it is possible to sand a hole in your cooler or significantly weaken the structural integrity of the cooler. When we designed our SratStar coolers for painting, we designed our cooler without aggressive textures to avoid this issue and only use sanding as a way to introduce micro-texture and to remove mold agents. Be careful not to remove too much material when sanding a cooler with an aggressive texture or opt for a cooler with a smoother paintable texture. 

rough texture frat cooler



Why Should I Prime My Cooler Before painting?

Primers Glue Your Paint to your Cooler

Primers are specially formulated paints that are designed to act as the glue between two different materials. Acrylic paints, like the ones used to paint a frat cooler have no properties which help them stick to plastic. Primers, on the other hand, do! The primers that we use on our SratStar coolers are specially chosen to to adhere to our specific plastic material. Have you noticed that when you hot glue fabric, you can not get the fabric apart ever again, but if you hot glue glass, it will peel right off? This is why using a primer and selecting the right primer for the material of the cooler and the paint is critical to keeping your paint on your cooler for years to come. 


Create White Base Color

Many store bought coolers come in extremely bright colors. If you try to paint directly over a bright red or blue, you will see the blue or red through your paint. You may have to out 5 or 6 coats on your cooler to stop seeing the color underneath. In order to create a nice canvas to paint over, you need to start with a nice even base color. 

 Color Why Primer a frat cooler


What Happens if I Don't Sand and Prime my Cooler?

Your beautifully painted cooler will chip and the paint will peel off. All the time that you spent painting will be waisted and you won't be able to go back and fix it after you have painted you cooler, so it is really important to prep your cooler correctly before painting! 

Unsanded Frat Cooler Chips


Sanding and priming are the two most important steps to ensure your paint will stick to your cooler for years to come. This process can be messy, time consuming, and difficult which is why we started SratStar! 

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