"WANTED"--Various plastic parts preparation methods before airbrushing

Probably the easiest clean up method is soaking in warm water and dish soap, rinse and let air dry.  A primer is a good idea afterwards, offers a good base for paints to adhere to.  I've been using Mr.Surfacer, thinned with lacquer applied with airbrush.

regards,

Jack

Hmm, you will probably get a million and 1 different responses on this one!! I personally only perform 2 steps on my builds in order to prep for final paint. If its an aircraft, I usually give the finally assembly a good wipe down with some 0000 steel wool. Armor tends to be a little more difficult and I usually just go straight to the primer step with it. Be careful with steel wool though as it will take away detail pretty quick if you get carried away with it. This roughens the surface a little and gives the next step , a primer coat, a bit of a surface to bite into. Afterwards, I airbrush on a flat enamel in a neutral color. Lately I have been using flat gull grey in the Model Master enamel line. I only finish with acrylics and thin most of them with 91% ISO although there are a few that just don't like it. I usually end up applying tape to the paint within minutes of painting an area and sometimes this tape stays on for days at a time, even weeks. I only use Tamiya tape which is fantastic. Ever since following these steps, I have had zero paint lift off of any build.

You didn't say if kit was styrene or resin.  Resin kits often have a mold release that must be washed off. I seldom wash styrene kits, though there is one company (forget which) whose styrene appears to have an oily contamination.

Ordinarily I prime directly on styrene without washing.  I use Krylon primer which has a pretty good bite.

Also, what type of paint are you using.  Some types have worse adhesion than others.

I've noticed a lot of the Zvezda kits still have a good bit of mold release agent on the sprue. I too hardly ever wash a styrene kit but I will have to on the Zvezda kits I own. Seems I recall seeing a lot on some ICM kits as well.

I do not wash styrene before I began assembly because to be perfectly honest I don't even think about it until its to late!

Now if I do lots of handling, puttying, filing, sanding etc. I do wipe off the model with one of those lint free microfiber towels soaked in water with a bit of detergent in it.

I also sometimes wipe the model with one of those "tack rags" that furniture finishers use. Especially larger models or one those needs to have an absolutely smooth finish, like a car.

I've heard mention in other forums of a "plastic prep" that comes in a spray can that many users swear by. I forget the name of it but do remember its pretty pricey.

Poly S plastic prep, By Testors (Poly Scale).

I wash in warm, soapy water, rinse and  air dry.  When ready for primer, I scrub seams with an old toothbrush, go over all surfaces with a tack cloth, then prime with enamel and paint with MM enamel.

I don't anything to clean the plastic, as if there is any release agent or finger prints on it from building it, it will all get washed off when I wet-sand the entire model down to finish off the joints, etc.  I do quite a bit of fine wet sanding to prepare for painting, and that will certainly take any crud off.  After the last sanding session, I avoid touching it as much as possible so as not to get any skin oil on it.

The only time I've had a problem with paint peeling after it has been airbrushed was when I used acrylics. And that was when I tried applying tape to mask it for a different color to be applied.  That was probably due more to the paint not being completely cured or the tape being too tacky. I hardly ever primer a model before I paint it. I don't always wash the plastic before painting either but when I do I usually use glass cleaner or denatured alcohol. Most of the time when you have a problem with paint peeling or coming off after it has been applied it is due to not allowing the paint adequate time to cure. In that case I'd go for a little overkill and give it several days or possibly even a week or more to cure completely.

I'll chime in:

I never worried about washing my styrene kits before airbrushing, until the day I started spraying a bunch of parts, and watched in horror as the paint puddled and separated all over the surface, instead of drying to a nice clean finish!

Now I don't take any chances...doesn't take long to dip the sprues in some soapy (Dawn) water, dab them with a sponge and rinse 'em off!  And it's worth the peace of mind, to me, at least!

As far as paint adhesion goes, I resist the urge to start working on freshly-painted parts for a couple days, to let them fully cure...I've pulled some paint up with tape before, and it's a bummer to have to re-do....I find that flat paints are especially prone to *grabbing* by masking tape.

Dave