Hello all, I recently stripped the paint off of a plastic Athearn model using hardware store-bought paint thinner without problem; the paint came off quickly and I further prepped the model for painting. When airbrushing the model, I inadvertantly sprayed too much paint one one side which led to the paint pooling and dripping down. Eager to fix the mistake, I then took the same paint thinner and began to rub off the wet paint with a paper towel dipped in thinner. This time, however, not only did the wet paint lift off, but the plastic underneath the paint began to curdle, bubble and welt... it was obvious the plastic was being damaged. My question is this: Why, when first stripping the factory paint did I not run into any problems, but after removing wet acrylic paint (airbrush mistake) did the plastic become damaged? Is there a paint thinner that is known for not damaging plastic? How should I fix my "paint pooling" mistakes in the future? Wait for everything to dry completely and then strip again? Also, is it a necessity to remove factory paint before dressing a model in a new paint scheme? Thanks in advance for any help you can offer!
Isopropyl alcohol works well and won't damage plastics. Since you are in the USA you should be able to get the high strength stuff (> 90%) at your local pharmacy. Ammonia based window cleaners (like Windex) work really well at getting acrylic paints off when you make a mistake - you can also use Badger Airbrush Cleaner if you can find it (very similar to Windex but specifically formulated to take off acrylic paints) For those of us in countries where the only isopropyl alcohol available is the 70% stuff, Windex make a good substitute - it will strip some paints very well. Not so sure about Kato and Windex, I haven't tested. Kato paint is notoriously hard to remove and most paint strippers will severely damage the plastic that Kato uses. Isopropyl alcohol is regarded as the only way to safely strip a Kato shell.
Hi Rob,didnt know we had more Aussies here.I can get 99% iso at my local chemist.500mls about $25,add 40mls of water to that 500 mls will get you a safer 91%.
I nearly fell over when my chemist told me it was $25 - I just couldn't do it - I'm an American ex-pat and the stuff should be 99 cents a liter! If I need to strip a Kato...
I have used the 70% alcohol. I have even had Aztec nozzles soaking in it for two days to loosen old acrylic paint. It loosens and then will come off.
I've had to special order the 91% strength at a local pharmacy. It was about $2 a liter (quart), versus $1.49 for the 70% strength at a Wahlgreen's drug store. I can get the 70% strength for $.25 a quart at a surplus store.
I got some 99% and added water to get around 90%. How long does it need to soak? Minutes? Hours? Days? Thanks, Loco1999
Just grab an old tooth brush & scrub away till paint comes off,wouldn't advise hours or days though,just scrub till it comes off (would advise safety glasses,you dont want alcohol in your eyes!). Rereading the original question,makes me think maybe there was a chemical reaction with the water based paint & paint stripper.If using acrylic paint & a mistake happens,just wash paint off with warm soapy water .
Thanks for the info. Those shells soaked overnight and the paint still won't come off. What am I doing wrong? Loco1999
Hello, There was a product made, expressly for removing paint from plastic. I have two bottles of it, and would tell you more, but of course, I can't find them. Some people have used brake fluid. It works. You may need to use a toothbrush for more thorough removal. I do not attempt to remove every bit of the factory paint. Most of it is very thinly applied, anyway. For removing acrylics while still wet, do as suggested above and dip in soapy water.
with stripping, its always good to start with less agressive meathods and move up. If Iso isn't working, then move up to Easy Lift Off. It is safe for most plastics, but don't soak overnight in ELO! http://www.testors.com/catalog_item.asp?itemNbr=1641
yankinoz and jason, being an expat aussie in septic land (sould I change my name to ozinyank?), I'm only too aware of the exhorbitant prices you pay retail over there. My advice is, find some occupation that uses iso commercially, then call one of em from the yellow pages and ask em where they buy the stuff wholesale. You might have to buy it buy the gallon, but the price will be way down there like it is in the USA. I recall using isopropyl alcohol for something a few years ago and it cost bugger all..... You could even just try calling around the chemical manufacturers in the yellow pages and see who is making the stuff. Trust me, the mark up from manufacturer to wholesaler to retailer is AT LEAST 100% at each leg of the chain, so prices blow out real fast. Aus lacks the competition the septics enjoy. As for your plastic having a heart attack.... 3 possible causes. 1) You used significantly MORE alcohol the second time. 2) the plastic was 'sensitized' by the first application and the 2nd kicked it over the top (ie, the plastic was slightly deformed, but not enough exposure to make it go ballistic) or 3) a chemical reaction to that particular paint...it doesnt take much %age of a chemical to make it go really silly. Acrylics are water based and recommend water for clean up...seems like a good plan to use the recommended clean up medium to me
