Sanding between primer and color coats?

thespaniard180 wrote:

So if I understand you correctly, sanding after the primer coat (assuming the primer coat went down without orange peel, etc.) is needed only for cosmetic reasons?

Exactly. Otherwise it is not necessary to sand over your primer coat, you can just go ahead and paint on your color coat.

You want to look for things you may mave missed prior to painting primer coat. Most cases the primer coat will make small imperfections, indents and scratches stand out. Yes, most are cosmetic due to handling, mistakes or things missed while assembling.

Primer coating surface of model before painting color coat actually makes your color coat bite down harder to the model surface so that when you start masking process the tape will not peel your color coat when you remove it. I usually apply two primer coats and between coats is when I look for things I did not see before and fix them before painting second coat. After that I am ready to paint color coat and finish my build.

thespaniard180 wrote:

I did a brief search and it seemed like sanding between the primer and colored coating of paint isn't always necessary. When might it be necessary and when might it not be necessary? I will prime with MM acrylic white primer and cover it with MM flat black acrylic or a mixture of MM flat white acrylic and flat black acrylic. Once the MM acrylic white primer is completely dry, is there any reason to sand (or wet sand)? What should I look for to decide whether to sand or not? Thanks

To sand or not to sand... that is the question.

Depending on how carefully you assembled your kit and did not scratch, dent, or other caused some small damage that would require sanding than your OK. I use Games Workshop Skull White spray paint as a primer and it sprays on very fine, infact it rivels Tamiya L Fine White spray primer. What I look for are small imperfections or some small damage from handling that may show up later when you paint primary colors. You will want to repair that before you paint your primary colors. This may require some small gaps that need to be filled or a scratch that will need to be sanded away. Use a magnifying glass or Opti-Visor and look for things that could show up and ruin your finish. If the none of the above are present on your model than no sanding is needed.

Another thing to watch out for when airbrushing primer is orange peel effect. This is a pebble look that will appear on the surface and will definately need to be sanded away and the model surface smoothed to allow repainting. This often happens when you airbrush to far away or paint drys to fast.

Good Luck.