Remove Paint From Plastic???

The MP40 modelgun/dummygun I just got in has black plastic grips [nice condition] and black plastic 2-piece forearm...painted brown...

The brown is a crappy job; lots of dust or grit in paint - at least that's what it looks like...



Anyone know a solvent or stripper that will remove paint but not attack plastic??? (Soap & water don't work!)

Thank You!

Hi richie328,
You can try oven cleaner products, Easy-Off Oven Cleaner(not sure of the brand) it's a spray foam which contains caustic soda.
Personnaly i used it when i failed painting plasic models kits.
You spray it generously on your plastic parts, then you wrap it in a plastic bag, close it carefully, wait about 24 hours, and you brush it with a nail brush under clear water. The old paint will go easyly without attackin the plastic.

Folks who make tank/airplane models have a variety of methods for removing paints. There are different ones for acrylic and enamel ones. You might want to check on a modelling forum or guide.

Some of the products can change the plastic surface, starting from making them slightly matt to making holes ;-)
Some are industrial ones and you can buy them in a tool shop, some are modelling specific. Chemical composition is similar, but pay attention to details. For example brake fluid (glycol based) DOT3 can be used quite safely, while DOT4 will attack the plastic. Oven cleaner (I think it isopropyl alcohol is the working medium there) works quite ok on acrylic paints.

I use a local product (WAMOD acrylic solvent) that is likely not available outside of Poland. It removes acrylic and enamel paints as well as varnishes, while keeping plastic untouched. It works almost instantly, no need for longer bath. It's based on glycol mix adapted to modelling plastic.
http://wamod.w.interia.pl/zmywacz_a.htm
WAMOD main page:
http://wamod.w.interia.pl/oferta_a.htm

Make sure you test a small area (preferably hidden) first to monitor for unwated reactions.

smootik wrote:

the plastic. Oven cleaner (I think it isopropyl alcohol is the working medium there) works quite ok on acrylic paints.

Hi smootik,
I though that soda was the working medium, maybe i was wrong?
But it work with enamels. Of course, as you said, it can slightly change the the plastic aspect.

Many thanks for suggestions! I would never have thought of oven cleaner.

I have brake fluid on hand; I may try that in small spot on plastic and see what happens. Brake fluid is stored in plastic bottles; and I know it removes car paint...

WAMOD spounds good but can it be shipped internationally???

I will try to find airplane/tank forum and ask about paint removal...

Don't know about ABS (which I'm guessing the part in question is made of) but I've used brake fluid when paint stripping styrene model kits, with good results. Pour fluid in a jar of some sort, immerse part and let soak overnight.

Just use protective gloves when handling brake fluid - it's seriously toxic, carcinogenous stuff.

In case you'd want to add a bit realism to your (what I too presume is a Denix MP40), ZIB-militaria sells Bakelite handguards for the replica in question:

http://www.zib-militaria.de/epages/61431412.sf/en_GB/?ViewObjectID=26133329

Suomi KP/-31 wrote:

In case you'd want to add a bit realism to your (what I too presume is a Denix MP40), ZIB-militaria sells Bakelite handguards for the replica in question:

http://www.zib-militaria.de/epages/61431412.sf/en_GB/?ViewObjectID=26133329

Thanks for the link! But I want to strip brown paint off to black plastic to match grips...

Dronne wrote:

I though that soda was the working medium, maybe i was wrong?

Checked now - soda is one option and it's in oven cleaners I think.
The cleaner that I used is different, it has isopropyl alcohol. I wasn't clear.

WAMOD doesn't ship directly, they sell through local retailers, so I don't think this is the best option.
It was just to say that modelling guys for sure have their local favourite mixture :-)

Good point about brake fluid: HIGHLY TOXIC.
Use gloves, and protective glasses!
Better be sure than sorry, especially with eyes.

richie328 wrote:

Thanks for the link! But I want to strip brown paint off to black plastic to match grips...

You're very welcome. And yes, agree with you totally, the grips should be Bakelite too for authenticity.

Suomi KP/-31 wrote:

And yes, agree with you totally, the grips should be Bakelite too for authenticity.

I too would prefer Bakelite furniture for authenticity; but not worth it for Denix. If I re-do furniture in Bakelite, it will be for my early MGC68 MP40...

I like black furniture on black metal look. Brown is OK, but black is more sinister...

I tried soaking the forearms overnight in brake fluid [DOT 3] and scraping them with a plastic scraper this morning...Partially successful...And no reaction to plastic finish...



What's left is pretty hard...Didn't want to scrape off...

I'm going to run down to the supermarket in an hour or two and get some Easy-Off oven cleaner...If that doesn't work, I'll try some Citrus-Strip, which I know works good for stripping paint off wood...And it's in a plastic bottle, so may not react with the forearms...

Edit: ARGH!!!!! I get to the supermarket and there are *TWO* Easy-Off oven cleaners!!! One contains lye, the other is glycol-based!!! I can't recall which was suggested here, so I get the one with the lye base...The glycol-based cleaner is for self-cleaning ovens, which haven't been around all that long, while I can remember my mother using Easy-Off back in the 50's/60's...So the lye based must be the well-established standby...I'm doing a bit of testing in an unobstrusive inside spot to make sure it doesn't affect the plastic...

Hi richie328,
Are caustic soda or soda mentionned in the content of the product?

Dronne wrote:

Hi richie328,
Are caustic soda or soda mentionned in the content of the product?

"Sodium hydroxide [lye]" is the 'contents'...Which seems to work, as after a couple hours, I was able to scrub the paint off...



Now I am down to the surface of the black plastic, but as you can see, there has been a change in the color...I think this is oxidation of some kind, and now I am faced with what to do next...

1. Spray with clear lacquer/enamel
2. Spray with black lacquer/enamel
3. Use polishing or rubbing compound on the whitish-gray surfaces
4. Use auto wax on the whitish-gray surfaces

There may be other options...

I decided on # 3 followed by # 4...



It takes a bit of elbow grease, but the white oxidation (or whatever it is) came off with Rubbing Compound. In my work, I've found three compounds for removing surface oxidation - Grinding Compound (used to seat automotive valves - coarsest grit), Rubbing Compound (medium grit), and Polishing Compound (least coarse). I then use automotive paste wax.

For this application, polishing compound had no effect, but the rubbing compound did. The two halves above are Before and After.

Thanks to all who suggested a solution to my problem!

I'm glad it worked :-)

I was going to suggest polishing the whitish surface, lacquer or paint is going to fill it in and complete the surface, as you found out.