Enamel spray painting questions ?

[modelwarrior]

Airbrushed some enamel today for the first time using AK Rust streaks and Vallejo airbrush thinner. Seemed to go perfectly apart from two small issues. Cleaning the airbrush afterwards was a real pain in the arse and the plastic I painted after 8 hours is still slightly sticky.
  My questions :

How long will Enamel take to fully go off on plastic and what is the best way to clean enamel paint from an airbrush(i usually use standard airbrush cleaner and airbrush cleaner brushes) ?
Also how long would you leave between enamel coats ?

 Thanks

[Fitz]

The airbrush can be cleaned with white spirit or turpentine, followed by warm water with some dishwashing detergent. If you want to be able to use it again for spraying acrylics you have to make sure you get rid of every trace of the spirit.

Avoid soaking it in spirit if you can, as that can rot the seals in the brush and valve.

Some enamels are known to react with the plasticizers and/or release agents in some moulded plastics to delay, or even prevent, proper curing. It pays to use a good primer before spraying an enamel top-coat.

[modelwarrior]

Sort of put me off using white spirit. Would white spirit not just evaporate after a short time anyway,thus saving the cleaning every trace ?

[2010sunburst]

Bit surprised you used Vallejo airbrush thinner….that’s designed for their air colour acrylic range, not for enamels?  Might be the cause of your sticky paint? 
To clean the airbrush, spray through with thinner to remove the residual paint, then strip it down and use liquid reamer or cellulose thinners to clean off any remaining paint residue.  Once the brush is clean, reassemble it and spray through with clean water to prevent damage to the airbrush seals.  The better quality airbrushes, Iwatta etc, will have seals that are impervious to any solvent, so this would be less necessary.

[modelwarrior]

Sticky paint is now dry so just reading on line its takes enamel a lot longer to cure apparently(24hrs). The airbrush was cleaned properly as usual but it just took a hell of long time to do. Also enamels and acrylic thinner is fine to use according to the web,just a slight different finish.

[2010sunburst]

I used enamels in modelling for many years (Humbrol, Testors, and Phoenix mostly) and would say they were always touch dry in about twenty minutes.  They took 24 hours to cure properly, sure, but were certainly not sticky after eight hours.  The best thinner I found for airbrushing them, by the way, was Phoenix Precision quick air drying thinners.  Sprays like liquid silk and is touch dry almost on contact.  If you are planning on using enamels a lot in the future it might be worth investing in a tin.
Still don’t get the Vallejo thinners working though  . Vallejo has water as a solvent and enamels has mineral spirits.  They are pretty much immutable.  I know enamel paint formulas have changed significantly since I used them regularly.  Some of the chemicals that made them work so well in the past have been banned, so perhaps that is the reason why this works. 
Still, if you get good results, and are happy with the way it works, then more power to your elbow buddy 👍

[modelwarrior]

It was a once off job spraying a large amount of terrain but if I ever take up hard core enamel airbrushing I will take your advice and buy a specialist enamel thinner.

[2010sunburst]

Good stuff!  I’ll shut up then 
Personally for hard core airbrushing I’d go for something else LOL….

[SteveBurt]

I suspect the water base thinner is the reason the paint took so long to dry. I’ve noticed before that solvent based paints go sticky if put on damp surfaces and take ages to dry out

[Captain Harlock]

You mixed basically acrylic resin with abit of flow improver and retarder with a solvent based paint. You were very lucky that it dried in the first place. Enamels can be thinned with white spirit or lacquer thinner, like the Gunze thinner ot the one for AK Real Colors.
You must always wear a good mask with filters cause these colors can cause many respiratory issues or allergies. I actually know such a case.