Metal Miniature primer test!

Tldr

Wash/scrub minis. Soak minis in 5% vinegar for exactly 2 hours. Rinse. Dry. Prime with gesso or Tamiya spray primer, or airbrush acrylic primer.

Tests

Tested a variety of priming methods, half the miniatures were soaked in white vinegar for 2 hours and then rinsed in an attempt to etch the surface to aid paint adherence. Durability was tested by scrubbing with a toothbrush for 3 seconds.

1. Paint: Tamiya Spray spray can primer
   Application: sprayed from can
   Notes: went on super smooth, I probably put it on too heavy
   Durability: Great, Minis soaked in vinegar 2 hours were best

2. Paint: Gesso from Hobby Lobby
   Application: Small cheap brush
   Notes: Using brush forced me not to miss spots
   Durability: Great, Minis soaked in vinegar 2 hours were best

3. Paint: Monument Hobbies White Primer
   Application: Airbrush
   Notes: Way better than expected for a plastic mini primer, almost as good as gesso, no thinning required for airbrush
   Durability: Very Good, Minis soaked in vinegar 2 hours were best

4. Paint: Tamiya Spray primer decanted and mixed 50/50 with airbrush thinner
   Application: Airbrush
   Notes: Clumped up, may have reacted with thinner
   Durability: Poor, may be reaction or un-evaporated propellant, vinegar treated worked better.

Summary

Wash, and Dry minis. Soak minis in 5% vinegar for 2 hours. Rinse and dry. Apply either generic store bought gesso with a brush or Tamiya Spray primer, sprayed from a can. These two paints worked best. Primer from Monument Hobbies worked almost as well (Don't switch if you prefer it). I didn't own any other primers to try.

Method

1. Wash and dry minis. I used Dawn dish soap and a tooth brush.

2. Vinegar soak

   Miniatures soaking in vinegar. The bubbles mean it's working! Not all miniatures provoke bubbling, so it might be working even if you don't see bubbles.

   

   This liquid probably contains metals you do not want to ingest. Dispose of properly. Rinse and dry the minis.

   Before and after vinegar treatment comparison, vinegar treated miniatures on right. You can see the patina etched in from the vinegar turns the metal dark.

   

3. Prime with your favorite primer. `

   Back row is Tamiya spray primer, Middle row is Gesso, Front Row is Monument Hobbies acrylic primer through an airbrush.

   

4. Paint

   Paint your minis. No matter what primer method I used, they all painted up pretty much the same.

   I painted these with Army Painter Speedpaints 2.0, except the eyes and mouths, which were Monument Hobbies Pro Acryl. The regular paints went on opaque to cover the speedpaints.

   I'm not a great painter, and playing games is my hobby, painting is not.

   

   For scale comparison, the mini on the right is 28/32mm, while all the rest are 15mm