Priming.

True primer will work better because the particles of pigment are usually smaller than in regular paint. They won't fill in the smaller detail as much. If you can't get primer, then use what you can get. I know that some people use automotive primers or Krylon laquer.

I wouldn't recommend priming with acrylic though, use enamel or laquer. One of the main reasons for priming is to give the final coats of paint something to adhere to and enamel or laquer will adhere to the plastic much stronger than acrylic would.

don't waste your money on those tamiya spray bottles of primer... sure, they work well, but for the price, they are not worth it.

I use Krylon light grey (for general useage)
and gloss black (for nmf)

If I don't have any auto primer, I'll use flat black, flat white or flat grey because I'm using it for two reasons basically - to help in the spotting of any imperfections I've missed and to give a good base for the color coats. I don't use reds because they can bleed through the color coat.

Usually you do not need to prime plastic unless you are doing a natural metal finish. As suggested, Krylon sandable auto primer works real well. Be careful as this stuff is toxic. Spray it outdoors and wear a mask to be safe.

Mike

I do prime, just to make sure the base coat is as close to perfect as I can get it.....and of course to check for gaps and such I may have missed.

Priming is great for spotting gaps and also for some hard to paint colors like white, red and yellow. Get true primer although sometimes I will use a basecoat of paint as a primer. Resin detail sets will need to be primed too.

Question: after using a sandable primer, do you need to wet sand if the primed surface appears smooth? Just wondering.

Mike