simple green not working?

[terminator ultra]

I've been trying to strip some space marines with simple green. I have soaked them for ages and used a toothbrush. some are painted with citadel some are not. Help wanted!

[Grotsmasha]

This is going to sound stupid, but is the liquid green? A while back Simple Green switched from a green liquid to yellow. The yellow stuff doesn't strip like the green did.

[pawl]

I'll soon be testing out a new chemical to see if it's better, but isopropyl alcohol has always done the job for me. =]

[terminator ultra]

15 hours ago, Grotsmasha said:

but is the liquid green?

yes it is.

 

7 hours ago, pawl said:

isopropyl alcohol

how safe is this?

[Firedrake Cordova]

IPA is fine for use on GW's plastic or metal.  I've generally found just dipping a toothbrush in IPA and scrubbing the model is enough - the paint tends to "jump off the model" and doesn't need soaking.

 

It can negatively affect resin though (like so many things), so I'd be careful with that.

Edited February 6 by Firedrake Cordova

[pawl]

1 hour ago, terminator ultra said:

how safe is this?

Don't set fire to it, don't get it in your eyes and make sure you've a little ventilation. Other than that you're pretty much fine! Gloves are best for longer exposure though.

The chemical itself is in a few hobby products, and is safer than those in some others!

 

It'll strip plastic, though resin can be a mixed bag - some resins may go soft in it. I've had plastic bits sat in the stuff for more than a year with no adverse effects to the plastic though.

[terminator ultra]

36 minutes ago, pawl said:

. I've had plastic bits sat in the stuff for more than a year with no adverse effects to the plastic though.

ok what happened?

37 minutes ago, pawl said:

Don't set fire to it, don't get it in your eyes and make sure you've a little ventilation. Other than that you're pretty much fine! Gloves are best for longer exposure though.

The chemical itself is in a few hobby products, and is safer than those in some others!

ok that sound good I'm going to hav another try with simple green first because I bought quite a lot of it

[pawl]

1 hour ago, terminator ultra said:

ok what happened?

ok that sound good I'm going to hav another try with simple green first because I bought quite a lot of it

Short answer? The paint came off. The plastic was exactly the same as when it went in - not softened or misshapen or anything. =]

 

Never hurts to try again! Sometimes breaking the surface and soaking again makes all the difference!

[terminator ultra]

20 hours ago, pawl said:

The paint came off.

well it didn't unfortunately

Edited February 7 by terminator ultra

[twopounder]

Ipa is only good vs water based acrylic. It doesn't work well on primer, but it can break down super glue. 

 

Simple green is a surface cleaner. It's not meant to strip paint and will never be very good at it. Same with brake fluid. I've never seen those work but people keep recommending them for some reason.

 

Goobertown recommends LA's Totally Awesome. You can find the YouTube video of him testing 6 strippers and it completely removed all paint overnight.

Edited February 7 by twopounder

[Firedrake Cordova]

I'm wondering if pictures would help? I've never had a problem with IPA or BioStrip 20 failing to remove acrylic paint (including Vallejo's polyurethane primer and varnish) - it's normally been pretty immediate! It could be that it's got a different type of paint on it, which would need a different remover?

 

This is the video @twopounder referenced.

Edited February 7 by Firedrake Cordova

[pawl]

I don't know, I've known iso remove acrylics and enamels (both humbrol paints and an enamel varnish), neither with any real difficulty. At worst I've had to leave them overnight with a couple of scrubs to break up the surface and let the iso in.

 

Again, I'll be testing a new chemical soon, so hopefully there will be a new player in the game before long!

[twopounder]

I used to usa ipa and I've had mixed results. Overnight usually loosens it all up and a bit of scrubbing with a toothbrush gets most of it. But it always leaves various amounts of primer behind. I've had it do nothing, even in 98% solution too.

[pawl]

Don't forget that if it was applied with a rattle can then the presence of MEKs or similar will pit the surface of the plastic very slightly, which could lead to some small amounts of discolouration even after cleaning. I've found before that (regardless of the age of the plastic) sometimes there are colours left behind - it's not actual paint on top of the plastic, but seemingly paint in the plastic.

It's certainly never caused me any issues though, so I don't worry about it too much and just prime over it.

[Brother Carpenter]

IPA stripped the models I immersed down to the primer. Apparently the spray primer is more resistant to the ipa I use.

Breake fluid will strip everyting down eventually. My other hobby is restoring a 1964 Ford Falcon and you won't believe how much damage (monenetary) a leaking master brake cylinder or just spillage can cause in automotive paint repairs.

[twopounder]

3 hours ago, Brother Carpenter said:

IPA stripped the models I immersed down to the primer. Apparently the spray primer is more resistant to the ipa I use.

Breake fluid will strip everyting down eventually. My other hobby is restoring a 1964 Ford Falcon and you won't believe how much damage (monenetary) a leaking master brake cylinder or just spillage can cause in automotive paint repairs.

 

Primer is not just paint, which is why IPA doesn't work well on it. Its chemically etched into the plastic to make a permanent bond and also has a rough surface to help bind paint better. IPA will usually thin it and can even remove some, but I've never seen it totally remove primer from a model. It usually does a good enough job though.

 

I had a friend in high school who left his models in brake fluid for a week (GW paints) and they came out exactly how they went in. This is probably because, just like refrigerant and gas, its not the same thing they used in the 50s. There are websites that warn about brake fluid literally melting through your engine. These websites are the same ones that tell you putting a battery on a concrete floor will destroy it. Both are true if we still live in 1935. Somehow these have become permanently affixed as canon in auto mechanic lore, almost to the point of being like the Adeptus Mechanicus.

 

I'll just leave an interesting blurb here:

 

 

I count 13 total brake fluid formulas that range from castor oil based to silicone based and have varying levels of corrosion. Which type you use depends on the brake system and local regulations.

 

TLDR: Brake fluid is a catch-all term for a lot of different chemical cocktails and is not reliable like IPA, which is always a single chemical and so behaves far more reliably. Simply telling someone "use brake fluid" is a really bad idea. Future formulas may even damage polystyrene, as its not like the DOT requires testing against thermoplastics. 

 

I need to get some of LA's Totally Awesome to test, but everything I'm seeing shows this being the best option.

 

Here is another article over on DakkaDakka.

 

Its not a harsh chemical, doesn't off gas noxious smells like IPA and does a really good job from everything I've seen. Its on my list for the next dollar store visit.

[AlexAbroad]

For brake fluid, the type that strips paint is Dot 4 (in the UK at least). You can get it from Halfords for very little. It will strip GW paints and even primers pretty thoroughly and can be re-used for more stripping. HOWEVER it is nasty stuff, you absolutely should wear gloves, do not use it on resin. and it needs to be disposed of properly (ie not down the drain).  I do not use it anymore for these reasons.
 

 I’ve found IPA or methalated spirits (the purple stuff) more than up to stripping both plastic and metal of GW paint without damaging. I’ve found both ok on FW resin when used quickly, don’t soak the piece but give it a quick scrub with a dipped tooth brush. 

[Terminatorinhell]

On 2/9/2024 at 8:40 AM, twopounder said:

 

Primer is not just paint, which is why IPA doesn't work well on it. Its chemically etched into the plastic to make a permanent bond and also has a rough surface to help bind paint better. IPA will usually thin it and can even remove some, but I've never seen it totally remove primer from a model. It usually does a good enough job though.

 

I had a friend in high school who left his models in brake fluid for a week (GW paints) and they came out exactly how they went in. This is probably because, just like refrigerant and gas, its not the same thing they used in the 50s. There are websites that warn about brake fluid literally melting through your engine. These websites are the same ones that tell you putting a battery on a concrete floor will destroy it. Both are true if we still live in 1935. Somehow these have become permanently affixed as canon in auto mechanic lore, almost to the point of being like the Adeptus Mechanicus.

 

I'll just leave an interesting blurb here:

 

 

I count 13 total brake fluid formulas that range from castor oil based to silicone based and have varying levels of corrosion. Which type you use depends on the brake system and local regulations.

 

TLDR: Brake fluid is a catch-all term for a lot of different chemical cocktails and is not reliable like IPA, which is always a single chemical and so behaves far more reliably. Simply telling someone "use brake fluid" is a really bad idea. Future formulas may even damage polystyrene, as its not like the DOT requires testing against thermoplastics. 

 

I need to get some of LA's Totally Awesome to test, but everything I'm seeing shows this being the best option.

 

Here is another article over on DakkaDakka.

 

Its not a harsh chemical, doesn't off gas noxious smells like IPA and does a really good job from everything I've seen. Its on my list for the next dollar store visit

I actually bought a bottle of LA to try and see on some old models. 

[Bloody Legionnaire]

What country are you in? I'm in the US and simple green has always worked for me. I've even had it work on models that have been finished in lacquer dullcote. I've used the concentrated version for both stripping models and cleaning paint out of my airbrush paint cup with no issue. For more stubborn paints, leaving it in the simple green, scrubbing with a brush, and then putting it back in the simple green for another soak has worked.

I'm very particular about my models looking great, and I've noticed that even if I can get ever spot down to the bare plastic, having most of it gone is good enough to preserve detail once I reprime and then paint the models. As long as you're clearing away the bulk of what was there before, I think you'd be okay. 

[Bloody Legionnaire]

On 2/9/2024 at 8:40 AM, twopounder said:

 

Primer is not just paint, which is why IPA doesn't work well on it. Its chemically etched into the plastic to make a permanent bond and also has a rough surface to help bind paint better.

 

There's a tiny bit of misinformation here; namely, not all primers all the same.. and a primer is not a primer because it "etches" into plastic, or whatever surface you are priming. The purpose of primer is to allow something for the subsequent coats of paint to "bite" onto and allow the paint to adhere better. I had never used primer before getting into this hobby, because my dad brought me up painting models with enamel and lacquer paints which are durable enough to go on to the model without primer in ways acrylic is not. 

Bottom line: A primer is not a primer because it "etches" into the surface of whatever is being primed. 

[The Unseen]

It could be that you have the all-purpose cleaner Simple Green and not the Industrial Degreaser. They look almost identical, but only one strips paint. The other makes a passable kitchen cleaner though.

 

 

[Bloody Legionnaire]

On 2/11/2024 at 8:51 PM, The Unseen said:

It could be that you have the all-purpose cleaner Simple Green and not the Industrial Degreaser. They look almost identical, but only one strips paint. The other makes a passable kitchen cleaner though.

 

 

 

I'm using the concentrated "all-purpose cleaner" and it does the thing.. 

[twopounder]

On 2/10/2024 at 10:53 PM, Bloody Legionnaire said:

 

There's a tiny bit of misinformation here; namely, not all primers all the same.. and a primer is not a primer because it "etches" into plastic, or whatever surface you are priming. The purpose of primer is to allow something for the subsequent coats of paint to "bite" onto and allow the paint to adhere better. I had never used primer before getting into this hobby, because my dad brought me up painting models with enamel and lacquer paints which are durable enough to go on to the model without primer in ways acrylic is not. 

Bottom line: A primer is not a primer because it "etches" into the surface of whatever is being primed. 

 

https://www.krylon.com/en/products/automotive/automotive-self-etching-primer

 

This is incorrect. All primers have bonding agents - this is what makes them different from paint. There is either an adhesive or chemical that reacts with the plastic (this is what I was referring to with "etching") that binds the pigment to the plastic and makes a rough surface that paint will more easily adhere to. The different bonding agents are like the difference between super glue and plastic glue. Krylon Fusion for Plastic, for example, uses a chemical reaction, which is why it only works on specific types of plastics (EDIT: I meant to say that component of it. There is still a bonding agent so it will work on others, which is why its Krylon Fusion all-in-one now)  and didn't need sanding or prepping. This can make it very difficult to remove from models, whereas water based acrylics will run right off.

 

If you're buying models off ebay, you have no idea what paints or primers they used. Some are going to be tougher to remove than others for the reason above.

 

I finally made it out and picked up some LA at the dollar store. Close to 4 liters for $5, so way cheaper than IPA. The results? Pretty fantastic.

 

The DWK had been stripped in IPA (several days and several washes to get to this point)

\

 

I had tested speed paints on these terminators

 

 

The Cataphractii were mostly primed with some dry brushing. This is how they all turned out

 

 

Granted, I forgot about them in my garage for a few days, but they were 90% clean. I just  need a very light scrubbing with a toothbrush to clean off the rest. As a great bonus, it also made the crappy blue tak I had tried to use come off pretty easy too. Going to throw that stuff in the trash.

 

 

Edited February 21 by twopounder

[Bloody Legionnaire]

1 hour ago, twopounder said:

 

https://www.krylon.com/en/products/automotive/automotive-self-etching-primer

 

This is incorrect. All primers have bonding agents - this is what makes them different from paint. There is either an adhesive or chemical that reacts with the plastic (this is what I was referring to with "etching") 

 

Excuse me? You are confused and then said my statement was incorrect while validating it. You claimed "etching" is what made primer a primer and it is not. Self-etching primers exist, that isn't what makes a primer a primer. A primer is used for aiding paint adhesion...

You stated initially: "Primer is not just paint, which is why IPA doesn't work well on it. Its chemically etched into the plastic," and unless one is using self-etching primer, this is incorrect information.

https://www.gizmoplans.com/self-etching-primer-vs-regular-primer/ FYSA

Just stop confusing people and then defending it.. 

 

Edited February 21 by Bloody Legionnaire

[Firedrake Cordova]

=][= Let's not get too bogged down in what defines a primer. It's fair to say that the chemical composition of some primers causes them to be very hard to remove, whilst others are easier to remove. Knowing what paint was used and its properties is helpful in working out how to remove said paint (or whether it can be) - let's concentrate on how to remove the paint.  =][=

Edited February 21 by Firedrake Cordova