How to correctly mix paint




Step 1: Read and understand the Material Safety Data Sheet

You must read and follow the Material Safety Data Sheet. It may detail specific ways that the coating is to be mixed especially if you are using a 100% solids material.

Step 2: Record your batch numbers and paint temperatures

Before you mix any material, check and record the batch numbers. You’re checking that the material is still within date range from the manufacturer. It's not uncommon to find the material from the storehouse is older than recommended. If it is outside the date range, confirm with the supplier that it is still usable.

Additionally, you need to make sure the paint temperature is at the correct point before staring. There is a storage and usage temperature range listed on the datasheet. Ignoring this can cause both mixing and curing problems.

For example: If the paint is too cold, you can get crystallization, separation of the actual resins - which may need to be re-blended with different equipment, to be able use it. If it’s too hot, we've seen fibrous fillers come out. And they literally get stuck on the bottom and you can't get them to blend back in.

Step 3: Pre-mixing?

You then need to check your A and B components to see if they need separate pre-mixing and determine if you are mixing a full pack or partial pack. When mixing a partial pack you need to be very accurate in your measurements, preferably measuring by weight.

Step 4: How You Should Mix

It’s important to select the right mixing blade because you don’t want the inclusion of air. Air often creates bubbles, and in certain materials, also adds moisture from the environment which is detrimental to the coating. For those interested, the mixer BlastOne recommends is the Jiffy Mixer, its two blades work very well.

Hold the drum between your feet, or use a drum clamp to hold the pot still. You then begin mixing - it'll create a natural vortex. Keep moving your mixing blade in the opposite direction to that vortex which prevents it from creating a spiral. Spirals will infuse air. And we already mentioned we don’t want bubbles or air moisture.

As you work with the mixer get it going and then start scraping the bottom of the drum until you are sure there's nothing left on the bottom and you scrape the sides - you lower the speed as you come up.

Step 5: Blending the Parts

So we have part A mixed, if you have to mix part B separately do that before you blend part B into Part A. following the same pattern as before. Typically, once the coating is visibly mixed, you should continue to mix at high speed mix for another 2 minutes.

Step 6: Adding Solvent

Never add Solvent prior to blending your complete Batch. Once you add Solvent, the shear drops, and it's no longer possible to get high energy mixing.

Step 7: Pumping the paint

Now that we have mixed paint, it's important to never pump from the mixing container. Why?... Because there's no solvent to integrate the traces of unmixed material which may be sitting on the sides of the drum.

The next thing to remember is you’ll need to change the drum you are pumping from at the end of the respective pot life. If the pot life is an hour, you will need to change your drum every hour or you'll get lumps in the material which won’t cure, and you'll eventually have to change the whole pump.

Final Safety Notes:

In most locations, mixing paint is recognized as a potentially explosive environment. It’s called Class 1 Zone 1 in Australia. This means you must use an Air Drill and ensure that your work practices comply with safe, flammable liquids handling practices, including precautions to prevent the buildup of static electricity. Some of these precautions include:

  • Only use metal drums. Don't use plastic pails.
  • Don't mix on a timber pallet, make sure you mix on the ground or on a concrete floor. That way everything is grounded.

We can assist with your paint mixing and application questions

Talk to our technical team to find out if your current process can be improved to increase your productivity.