Cleaning plastic before painting

Can I use use windex to clean the plastic before painting ?

2 Likes

Welcome! I bet you can use Windex but personally I use Isopropyl alcohol to clean my models. But Windex probably works fine.

Dishwashing detergent works fine, too!
:smiley:

2 Likes

I would be careful with Windex as it contains ammonia which dissolves latex (acrylic ) paint .
Iso alcohol would be safer - I always use Dawn dishwashing detergent.

If you do use Windex, just rinse the model off with water, let dry and then
paint.
Cheers,

i use Dishwashing liquid or ISO,in some country Windex contain ammonia,here you can buy with or without ammonia

I use Dawn dishwashing detergent. I figure if it can take oil off sea birds, it will work with my models. I used to use it directly in the sink but after losing a kit part a couple of times to the garbage disposal I wash in a separate Pyrex dish. I picked one up for a couple of dollars at the Goodwill store. The trouble is my wife thinks it’s her’s. Maybe I should get her one for her birthday! Nah, I 'd be in the doghouse for a while.
Take care and stay safe friends,
Don

1 Like

I thought I better include a word of warning. Dawn will work great on unpainted plastic, it has taken a little paint off of a model I was working on.
I solved that problem by using Ivory dish soap instead for painted surfaces. My wife can’t understand why we need 2 different brands of dish soap.
Take care and stay safe friends,
Don

I generally wash my unfinished models before I paint them. I do this as subassemblies and / or individual parts.

I wash these in warm, soapy water in the kitchen sink (with a stopper in place), rinse well in clean, warm water, and allow them to air-dry overnight. When washing I use a large, soft water color brush to gently agitate and scrub the surface. If I have lots of small details or potential for parts to break off, I’ll use a large plastic bowl rather than the sink, and carefully examine the sediment on the bottom before pouring it out. After I rinse, I place the subassemblies and parts on paper towels to soak up the excess water and hold them while air drying. I’ll often use the kit box and / or lid to hold and move all of this.

I also check any places where water could have accumulated and not dried out by using my airbrush as a compressed air gun, blowing into the nooks and crannies to force any water out before I start spraying paint.

There is usually a lot of surface contaminants that accumulate over the course of a build, and not just the possible mold release agents that might be on the surface. There’s dust from the air, there’s sanding dust, there’s swarf from carving, filing, sawing and drilling, etc. A thorough cleaning is a good practice.

Cleaning the surface before painting also means that I don’t generally spray any primer just to improve paint adhesion. Any primer’s I use are selective and judicious for purposes like checking filled seams or to create a uniform base color to help with subsequent finish coats.

I have used Windex for years and have had no problems with it at all. I should probably clarify that I use it on the bare plastic and nothing that has already been painted. Once I have all of the subassemblies completed I spray them with Windex and then rinse everything off with warm water. Once everything has dried it is ready for the base coat of paint. That’s my process anyway. :slight_smile:

Randy