Primer and acrylics

I usually prime all black before adding the final paint colors, I started doing it for preshading and found that the paints do stick better and no longer come up with the masking tape.

I always prime with black Vallejo poly primers.  It also serves as preshading.  

I always prime unless I am doing a cockpit interior or wheel wells which won't be masked.  My experience is that Model Master priming is a requirement as it has poor adhesion over bare plastic.  I did the wheel wells of my last 109 without priming using Vallejo Model Air acrylics and I tested the overspray on the wings with both Tamiya and Scotch Blue tapes and neither pulled it up.  No real experience with Tamiya as I only have used it on armor which I always prime.

I use Vallejo's acrylic polyurethane primers.  I have three colors; grey (which dries almost white), panzer dark grey and black.  You can mix them to get whatever shade of gray you need.

Better safe than sorry would be my recommendation.  As others have said, priming is useful in reviewing your work before the final coat(s).

John

I think priming is a good idea whatever type of paint you are using.

When I do prime,I use Tamiya Fine White Primer or Mr Surfacer 1200,both in the rattlecan

I primarily use Tamiya acrylics (airbrushed) and have never really had a need to use a primer.

However, when brush painting with Vallejo Modelcolor, I like to apply a primer coat (airbrushed) of a suitably coloured Tamiya flat acrylic.

Do you airbrush or rattle can primer?

I just read  Vallejo recommends to use primer on all there acrylics. I have used it both ways and it does cover better with a base at least on larger parts it makes a difference.