I gave this primer another chance, trying to finish my Warspite gun turrets with MM acryl primer airbrushed on a clean surface. Terrible results, tried to mask it off with Tamiya tape and when removing tape the paint did not adhere at all to surface of turrets. What a waste of time? never had this problem with Alclad lacquer. Anyone else try this stuff?
welcome to the forum. can you provide a few more details please? Did you thin the primer? if so what did you thin it with? what ratio of thinner to primer?
I used to be on the “old forum” for a long time,thanks for the welcome. no thinner, it airbrushed on perfectly with no thinner. I do have Testors Acrylic thinner. why would thinner make it adhere better? thinner is used for better airbrush flow? or am i missing something here. Thanks for your help. 
Gotcha. Welcome to the new forums long timer:)
First I’d thought maybe too much thinner or non-compatible one had been used. Then it sort of hit me isn’t MM Acryl Gray Primer a color NOT an actual primer? MMA sprays well and adheres poorly to plastic unless a real primer is used in my experience. I think its necessary to prime before using the primer gray color.
Hopefully one of the more acryl savvy painters will chime in.
all these years I thought this was a primer! wow…how many others have made my mistake? So Model master 4680/grey primer IS A COLOR! thank you so much…live and learn even at my age. Back to using Alclad primer before acryl paint.