The paint mixer is responsible for mixing paint for the painters. He/she tracks supplies and material usage. They are also responsible for tracking/flagging paint hours for their shift. RESPONSIBILITIES. • Mixes paint (solvent and water base) for use in painting according to formulas.When you don’t get your paint mixed well enough it can wreak havoc on your project causing you to spend even more time sanding and repainting when all you want to do is be DONE WITH THIS PROJECT once and for all. Mixing you paint properly is KEY. You can shake it (just make sure your lid is on tight or you could end up with a mess like I did that one time…)or you can stir it with a stir stick but unless you REALY spend a lot of time doing either of those tasks, you’re not going to get it well enough. Using a paint mixer in your electric drill is the best way to get your paint mixed properly.