Gloss paint drying matt

[danbuoy]

I'm using a spray can of Humbrol Acrylic 15 Gloss Midnight Blue, to respray a diecast model. Its going over a coat of Tamiya light grey primer. First coat went on fine, nice and glossy, but 2nd and 3rd coats are distinctly matt in patches and I cannot work out why. All three coats have come from the same can, which was thoroughly shaken before use, and the can held the same distance from the model. There were over 24 hours between each coat.

 

After realising how little you get out of one of these cans, (I initially decided on this route because I thought it would be less faff) I have done some other diecast models using the Humbrol 15 enamel from my airbrush, which has gone on nicely, with 2 or 3 coats per model.

 

Now I'm wondering what to do about the problem model. Should I try another coat from the spray can or can I try spraying the enamel paint from my airbrush over the acrylic that is already on the model (once acrylic is fully dry)?

 

Or do I bite the bullet, strip the paint off again, re-prime and start again?

[Steve Noble]

Are you spraying in a moist environment? Sometimes with acrylics they can take on moisture from the air and go matt, the technical term is 'blooming'

[danbuoy]

It was in the shed, but I think both evenings it had been raining, though not actually when I was spraying but it was moist outside and door was open.  Would that be enough? Not the warmest evenings either, especially for July. 

[Steve Noble]

It's possibly moisture from the air. Try to respray when it's warmer or in a warmer place and it should be okay then..

[sapperastro]

Also, try warming your spraycans. immerse them halfway in a bowl of warm (not hot) water for 15 minutes or so. I find this also improves the experience.

[danbuoy]

Thanks both. Weather is much better this weekend. I can only really do any spraying in the evening and forecast looks slightly better for tomorrow so will try again then, after warming can first.

[danbuoy]

Well tried spraying again last night, on a much warmer and drier evening and after letting the can sit in some warm water for 15 minutes. Result, perfect gloss finish! Thanks for the advice! I'm amazed at what a difference a slight change in the weather made though between the 1st and 2nd & 3rd coats.

[Steve Noble]

Yes, weather can make a massive difference. It's a problem I used to have a lot when I used Halfords rattle can paints, especially with the Appliance White, it always went matt finish in the cooler, wetter months. I used to warm the can and warm the model parts gently with a hairdryer, before and after painting to prevent it. Glad you are sorted now and happy if I helped 😀