For acrylic paints, such as Polly Scale, I have had fantastic success with Windex and a toothbrush. It worked almost instantly and I didn't notice any damage to styrene or resin models.

Great tip thanks!

For N-scale I've had good results using Scalecoat paint stripper, except for yellow.  Yellow will eventually come off, but it takes longer, so you're pushing the safe limit for damaging the plastic.  Don't try to get every last bit of paint off if it doesn't want to come. Settle for a smooth finish of residual paint.  You won't see this after repainting anyway.

10 - 20 minutes at room temperature is about right, but err on the side of caution.  Experiment with some old shells first!  Scrub gently with a soft toothbrush to get in the cracks.   When done wash completely with dish soap and a toothbrush to remove residue.  Don't throw the used stripper away!  Put it in a separate container and let it sit.  After a week or so most of the dissolved paint will settle out and you can reuse.  When you do want to get rid of it., take it to a paint store or gas station to recycle, or like me, you might have disposal facilities where you work.  Protect the environment !  

Brake fluid works too, but it's really nasty stuff and you can't see what's happening.  Scalecoat is clear and made for the job.  Use it instead.

My best results have been with Atlas, MT, MDC and Athearn.  Quality plastic is more resistant to damage. Be very careful with Bachmann and Lifelike!  Their plastic doesn't stand up well to paint remover.  Try isopropyl first.

Scalecoat stripper can also be used as a weathering technique by arresting the process early with dishsoap and water.  I've had good results here, especially with boxcar red, but definitely experiment first!  

ebear

My last resort is blasting with baking soda.   For older MTH (O scale) models I have found no chemical that will even soften much less remove paint without damaging the plastic.   Even then, for an 18" passenger car, using a full size sand blaster @90PSI it still takes 4-10 pounds of baking soda to clean the shell completely.  Unless it's done in a closed cabinet the medium will get everywhere (as with any blasting medium) but at least it's environmentally benign.

Richard

Denatured alcohol is the solvent in brake fluid.  The biggest difference is that the denatured alcohol is mixed with a lubricant in brake fluid.  I've also found that Pine Sol used full strength will remove paint form old Athearn shells.  They have changed the paint on their new r-t-r models, and I assume the same is true for the Genesis line as well.  I friend of mine and I were trying to get paint off a new r-t-r Athearn Gp50, and found that the only solvent that worked without damaging the plastic was Scale Coat rinse away.  The denatured alcohol and Pine Sol did nothing and we didn't want to try more caustic chemicals for fear of damage to the plastic.

Don't get denatured alcohol confused with Isopropyl alcohol rubbing alcohol. Denatured alcohol is what is also called wood alcohol or ethyl alcohol. these are poisonous to drink unlike Grain alcohol that is used in booze and is made from fermented corn drippings.

Isopropyl Alcohol is used for First aid treatment of minor cuts and skin abrasions and many times used to cool people with high fevers and it also contains distilled water. It isn't a poison but if adjusted it will cause great stomach discomfort and extremely painful cramps if a small amount is swallowed

Denatured alcohol will strip a number of paints and dissolve some plastics and Isopropyl alcohol won't bother most paint or plastic.

Dan

is alcohol based... why not stick to alcohol?

And, as noted, do not confuse wood, grain, and Isopropyl alcohols... some are natural, some refined, some poisonous.  Also, Pure grain alcohol (90+ %) can be obtained at liquor stores.

Denatured alcohol will strip a number of paints and dissolve some plastics and Isopropyl alcohol won't bother most paint or plastic.  Paint stripper that won't bother most paint?!

The stuff I use very effectively is labeled "Isopropyl Rubbing Alcohol 91% USP - First Aid Antiseptic" and a 16-oz. bottle cost me $3 at the drug store. It works on pretty much all plastic model railroad stuff except Kato. Lower concentrations of alcohol aren't very effective. The 91% can be reused -- mine goes through a paper coffee filter and back into the bottle after stripping paint.

The paint shop also has bottles of:

Testors ELO ($10.49/8 oz.) with glycol ethers and isobutyl alcohol

Scalecoat Paint Remover ($8.49, 16 oz., probably more now) containing secret stuff and a warning about using it on Atlas HO, and

Chameleon Model Paint Stripper ($6.99/8 oz.) which contains 2 propanol; dimethyl carbinol and 2 butooxyethanol.

You can see why 91% isopropyl alcohol is the first choice.

"hopefully more people will submit more"

Dan - what are you waiting for ?

About 91% isopropyl alcohol: Yes, it works well - I successfully stripped two Bachmann diesel shells and was amazed at how well it worked (did need an old toothbrush to get some of the stubborn spots, but they came clean with little scrubbing).

I've used 91% isopropyl to clean engines and used a tooth brush but, then most of my engines are Brass and almost all my older engines have been painted by me and 91% won't touch Floquil oil based paint. I've never tried stripping a Bachmann engine or washing one because I only own 2 and their both new and still in the boxes. But I have cleaned MTH Diesels with it and it never bothered them either, I wonder what kind of paint is used by Bachmann.

I'm glad you told me about Bachmanns engines I would have hated to ruin their paint.
When it comes time to clean them I'll just use soap and water and hope they don't paint their engines with water base paint.

Dan

Mark Schutzer recommends Jasco paint remover followed by bead blasting for work on brass locomotives. This stripping will effectively remove any epoxy so then proper repairs can be made via resistance soldering.  His work on his website looks very nice once this treatment has been applied.

What a great idea. Can't wait to try it

I use 91% Isorpopyl (rubbing) alcohol, or Scalecote Wash away. Sometimes original Pine-sol. The advantage with Pine-sol is it smells slightly better then the rest!

None have dried plastic out. The Wash away is the only thing I've seen remove both Broadway Limited (mentioned in the article) and Kato paints. Pine-sol does a number on diecast cars (aka the 1:87 matchbox cars!).

As stated, be prepared to leave the model overnight. I have an old pickle jar full of pine-sol for diecast vehicles. I have another, empty one that I use for the other two strippers, and I fill it for specific model I'm stripping.

I have a brass model I'll most likely be custom painting for a customer, I'll seen about submitting an article on how I do it.

There's one maybe a bit unortodox paint removing process which wasn't mentioned here, but was working fine with me and somebody might want to try. I am using an oven cleaner, "borrowed" from our kitchen (over here it's called "Mr. Muscolo" or something like that). You know, it's a spray which creates a lot of foam, which cleans the ovens... Anyway, it works fine with factory painted models of most kinds, and most importantly, without damaging the plastic. I have painted and repainted most of my models more than once, and all the damage on the plastic was always done only by me if I handle the shells too hard with the brush.

It takes a bit time though - spray the shell generously, then put it in a plastic bag, and seal it (you can put more shells than one in one bag, doesn't matter). Let it do the job over night, and next day wash it with warm water (using some toothbrush is helpfull). Most of the paint will peel off, and the plastic will be intact! If some paint is still stubborn on some places, simply repeat the process (sometimes the printed railroad logos on the shell can be stubborn to come off), but a stronger push with a toothbrush or some similar plastic brush makes it to go away. I have never checked what type of paint was used with different manufacturers, it worked equally well with most of them. Disadvantage might be that it doesn't really smell like roses, and it is suggested to use rubber gloves (which I usually don't, as never have them when I need them), plus my wife was angry on me a few times when she wanted to clean the oven and found the spray can empty...

Erik

plus my wife was angry on me a few times when she wanted to clean the oven and found the spray can empty...

Sometimes a household product is useful for a model railroading application.  In fact some times they are useful for other odd jobs around the house.  I have found that it keeps the peace with my wife, if I make a point of telling her anytime I borrow something out of the kitchen to repurpose for some other project!  It used to frustrate me at work when I would need to dump a bucket of used oil and the waste oil tank was full but the service manager had not been told that it needed to be pumped out.  There were any number of other little things around the shop that were frustrating just because people would break something or fill something and not let anyone know about the problem just leaving it for others to find!  It would frustrate me if I was doing a job around the house and went to use an item that I knew I had available, only to discover that my wife had used it for something else that made it unusable for my project (never happened, but it would be frustrating if it did.)  I presume that it would frustrate her if I took a cheap sponge that she uses in the kitchen and used it to clean the tip of my soldering iron without letting her know to put it on her shopping list for replacement.  Somtimes I will be going to the store, and just pick up whatever it is that I used or need; but if I use something from her kitchen, and am not going out right then, if I put it on her shopping list, and tell her I used it, it is much less frustrating for her.