As a pre-clarification to this video, my ire is directed to those who comment authoritatively but incorrectly on this subject not those who simply don't know or make a mistake - thought that was an important distinction to make!
Greetings from Canada. Superbly interesting video. Thanks for putting effort and research into this topic. I am wondering is there a "best" choice thinner for acrylic paints: for example, Tamiya can be mixed with water, lacquer thinner, acetone and alcohol, but is there one thinner it is most compatible with for durability, etc.
This channel is becoming so much MORE than just a “review model of the week” site. E.g., 1) Developing a metric for world’s best model company; 2) Expressing an understandable vision for improving IPMS; and 3) Explaining the chemistry of acrylic paints for non-chemists. Amazing scope, yet all are very well done. “Hat’s off to you,” Mr. Mann.
A friend recommended that I check out this video, and I really enjoyed it! There's so much wonderful stuff in here, thanks for making content like this :-) and... forgive me, but I must now point out a few minor quibbles hehehehe First Quibble: for the polymerization of acrylates, BOTH carbon atoms from the C=C double bond are incorporated into the backbone of the polymer, not just the terminal carbon atom. The double bond between them becomes a single bond, and each of those carbon atoms gains a new single bond to a carbon atom from another unit of acrylate monomer. The backbone of the polymer looks like this: (C1-C2)-(C1-C2)-(C1-C2)-(C1-C2). Your images of the forming oligomers are incorrect, ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-m9tPsNMa7Rk.html but the image of the full chain that you show later on is correct ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-m9tPsNMa7Rk.html Second Quibble: In your description of paint drying, you talked about the speed of polymerization. For most paints, the polymerization of the plastics in the binder is done before the paint is mixed, and the "drying time" really is just the solvent evaporating. The hardness and the durability of the dry coat come from tangled polymer chains, plus the difficulty of re-creating the emulsion / suspension that you described later in the video :-) Thanks again for a great watch! I'm always excited to learn more about paint 🙂
Hi Brent, thanks for the comment - as I'm a clinical biochemist, and you're a "proper" chemist, I bow to your superior knowledge of the exact mechanism of reaction! - my intent was to outline basics to non science people rather than experts! On the second point you mention, yeah, I glossed heavily over the exact mechanisms that paints cure, since it's very much determined by individual paint types. Of course for most, especially emulsions, the main polymerisation has already occurred, which I tried to show in the SEM photo, but again, lay people presentation rather than "peers". Of course this is generally only true for acrylics, not the other longer- curing paints like oils. Also must say that I am subbed to GH, and really enjoy your content - it was part of the inspiration I took for doing this in the scale modelling field!
Excellent. You obviously are a chemist as well as management consultant. This video was very imformative, even if difficult to follow. What we need next, as part 2, is what do we use with what brand of paint to get a good result, brush or spray.
Wow!!! This is WAY more info than I was looking for. I did'nt expect such detail and chemistry. I love it!!!! Thank you! I will have to come back and re-watch a few times to fully get it . Truly appreciate all you have done here. Thank you!!
It would be very helpful to have an additional video which talks about how the different categories of paint, enamel, lacquer, and acrylic, interact once they have cured. For example on a chemical basis, what happens when you apply a lacquer base paint over a cured acrylic base paint. is there any optimum order in which to do this? The advice one gets through social media is very confusing on this issue.
That's a great idea - I am going to do a follow-up video speaking about diluting different paints for use either by airbrush or handbrushing. This would fit nicely into that.
Thanks that will be extremely helpful. Could you also add in an explanation of the difference, if any, between drying and curing? Your videos are very well done and helpful.
There are two hazards when airbrushing any paint - particles of paint and the solvent. For Acrylic emulsions, you generally only need a particulate mask (N93) to keep particulates out of your respiratory tract. For anything diluted with organic solvent, you need something that is rated to trap solvents, so a proper chemical filter mask with replaceable filter cartridges
Thanks for that, a very informative video. On an allied topic most modellers are clueless when it comes to the terminology associated with the colour of paint. Any paint mark has four qualities - tone, hue, intensity and temperature. A review of videos or literature for artists will help clarify these terms.
Absolutely - I'd thoroughly recommend anyone watches art or mini-painting channels as they tend to cover colour theory and application much better than us as modellers!
Absolutely brilliant Alex. You explained the chemistry perfectly and made it fascinating. Even though I have been doing crystallography for 20 years I never thought it would be somehow useful in model making 😂 Keep things like this coming!
Thank you, at the very very least, if you are a youtuber, you should know this, but so many don't.. This leads to so many problems for people as evident on reddit
This is excellent material. A very educational video. Thank you very much for it. I have a doubt: at some point (minute 5 more or less) turpentine is mentioned as a mineral spirit. Perhaps I am confused due to a language issue (I am not a native English speaker) but I think that turpentine is a distillation of pine resin, therefore not mineral. Am I correct?
You're quite correct, my phrasing was "Mineral spirits like turpentine", which does sound like I'm grouping them together - I should have said "similar to" rather than "like". Turpentine (or oil of turpentine) is one of those "lighter oils" I mentioned, being derived primarily from pine trees and containing primarily terpenes - hence the name. Petroleum-based mineral spirits have largely replaced these as they are much cheaper and are available in finer-distilled forms that have very little odour compared to these compounds.
Brilliant! thank you so much for this, a breath of fresh air! Please have more of these if you can, going into more detail about the mixability of specific paints with specific thinners, it can help so many modellers finding new ways of doing things. For example, I only recently discovered that I can use lacquer thinners (like Tamiya Lacquer thinner, and Mr. Levelling Thinner) to thin 'standard', 'water-based' acrylics, like AK, MiG, Vallejo, and even Mission Models Paints (very surprised by that to be honest). When you first try to mix these with the lacquer thinners in a cup they seem to clump a little, but after some more mixing, it looks as if the lacquet thinner 'gets through' and they mix and thin and spray just fine. It's as if the paint 'finds its inner self'. Now, I know most people go the other way, prefering to avoid lacquer thinners and dilute everything with water and acrylic thinners (for very good healh reasons too), but being able to use traditional acrylics (which are also widely available and relatively cheap) both with their own thinners (and water) and with lacquer thinners, opens up so many more possibities, especially for layered weathering of our models. Not to mention avoiding certain, ahem, peculiarities, of branded thiners (looking at you, Mission Models 🙂). Any thoughts on this?
Yeah,it's a great point - this is mainly (I believe) due to the water content and miscibility with those limited water soluble components of the thinner (like isibutanol) - I think if you're adding smaller amounts of paint (and hence water) to the thinner, that is less of an issue. As always though, it will depend on all that "other stuff" in the mix and it's miscibility, which means the mantra will always be "test first"!
That was superbe Alex, took me back 40 years to O Level Chemistry 👍🏼 I didn’t really think about all the constituent ingredients other than the basic triad. Ian
It's a bit like being given a medicine for a disease or condition, and then being given another to counter the side effects, and then another to settle your stomach because of the other two medications!
@@MannsModelMoments I completely understand that analogy 👍🏼 As part of my profession I have some limited prescribing rights and had to do a pharmacology module in my post grad course. Anyone on long term multiple medications should be having a Pharmaceutical review for interactions and secondary effects. Under medical advice of course. Ian
Thanks for that. And by thanks I mean sod you! I’m off to Sainsbury’s to buy a vat of ionised water and I’m going to check all the labels on the ten plus makes of paints I usually use. 😀👍
I hear hobby painters say alot of things that dont make sense to painters. I think it stems from trying to save money, which is understandable. I heard a guy say "learn to thin your paints properly, and dont use additives" all in the same sentence.
I’ve always found the Tamiya acrylic paint in the little plastic lidded bottle was very “thin” and hard to use. I’ve always had best results with stuff like Humbrol enamel that uses turps to clean up. It can take longer to dry but seems to cover better.
The reason Tamiya paint seems "thin" are those alcohol and alcohol derivative components - it doesn't have the same surface tension or viscosity as the detergent modified water emulsions - making them easier to spray, but potentially more difficult to brush paint with
There is one specific Tamiya color I swear by: X-13 Metallic blue. I freaking love that one. I airbrushed my whole space marine army with it. It looks weird applied with regular brush, but through an airbrush, it is incredibly even and looks fantastic, even if you use matte varnish.
I had a great chemistry teacher back in the 1970's, but this was a revelation in how to make a complex subject understandable to a non-scientific person, thank you.
Stellar video. Two questions: 1. when native acrylic has set and dried is it soluble in organic solvents? It seems like the solvent can't undo the polymerization and when you wipe a lacquer painted model with thinner you're just breaking adhesion and "dissolving" larger polymerized chunks. Is that accurate? 2. what happens with the emulsifiers in acrylic emulsions as they dry? Seems like they'd just sit there a bit in the way. Is this why native acrylics set harder than acrylic emulsions (at least comparing mr color lacquer to vallejo or similar)? Also, I was always curious what enamels are - now I know, thank you!
I mean it really depends on the formulation that the company uses - any generalisation is just that - it's a bit like talking specifics about "insects" - they all have 6 legs, but an aphid and a Giant Asian Hornet bear pretty much nothing else in common! Depending on the solvent in a "lacquer" paint, you can potentially get some interaction with the surface chemistry of the plastic going on too (same with rattle cans). If you think about removing an acrylic-emulsion paint from a model, you tend to end up "peeling" it off the model - it's the bond to the plastic that breaks before the bonds with itself.
Holy crap, Alex, that was awesome!!! You really know your sh!t 🙂👏👏👏👏 How can a guy, who is two years younger than me, know so much more? After all, I have (a lot) more life experience - makes me wonder where my life took a wrong turn! 😎I am in awe of your expertise.
Very flattering, but it's just a matter of a subject being close to both my educational history and hobby, so it makes it easy for me. Ask me something about speaking languages or playing an instrument and I'd definitely be out of my comfort zone!
@@MannsModelMoments Haha, yeah, I know what you mean. Remember our conversation about "Sidkavitz"? Languages are kinda my thing - playing an instrument not so much 🙂But I do love it when you speak "Scienteese". Please do more of these, if time and effort permits!
Been working with acrylics for a few years, but only just (as in last few days) started using Tamiya. Needed a clear red paint and my water bourne ink wasn't working. So if I'm understanding you correctly, i can thin down the paint with water exactly the same as my other acrylics? This is good news, as it'll make them much easier to deal with, but also surprising, everything I've heard about them said IPA was a must. The bottles don't help themselves tbf, the number of warning messages makes it feel like you're painting with something that'll kill you if you do much as glance at it 🤣🤣
Well, just because it's water-miscible doesn't mean you can thin it as other acrylic emulsions - it really depends on what you're thinning it with. As I demonstrated in the video, you CAN thin with water, but it doesn't yield optimum results, because of water's unusual properties.
I speak as someone who used to make this mistake: you can dissolve tamiya acrylics in alcohol, but it will be a soupy, messy and lumpy mess unfit for airbrushing. The fact is you're far better off using their X20A solvent or mr color levelling thinner simply because they are superior carriers (meaning: the mixture won't be lumpy and runny)
I found this video very interesting, educational, and found nothing wrong with it. Factually, it's solid, and explains some nomenclature channels folks have fallen into like alcohol lacquer, or acrylic lacquers, or water acrylics, etc. This videos does a superb job of explaining what the chemistry is in the different paints; the pigment, the binder, and the solvent. Like talking about the surfactant based paints such as Vallejo, and AK 3rd gen. Or alcohol solvent acrylics like Tamiya and Mr Hobby. Perfect job Alex.
I started off using water as a thinner for Tamiya paints, then moved on to IPA and MLT. With Mr Color I always used MLT. People always told me how lucky I was it worked for me and water doesn’t work as a thinner for Tamiya. Never had an issue. Not once. I did with Mission model paints. Only their thinner works with their paint. The amount of colors that work with other thinners is so miniscule, not worth trying.
It probably didn't work for them because of some of the issues I mentioned in the video - hard or different pH water, as Tamiya can easily be thinned with water (though it's not ideal for its properties as I showed in the video)
It just goes to show the chemistry that paint companies put into a little bottle is very good that in MOST cases they can cope with some if the rubbish that's added to them, but if we think about what we're doing, we might get better results rather than just blaming the paint and not learning anything...
Incredibly well put together. Thank you for making this! Please make more educational content about our hobby! It is such a joy to have a deeper understanding of what we are using / doing!
What do you mean by "is it ok?" - if you mean will it mix, then yes, Tamiya will mix with both IPA and water. Vallejo paint it will depend on how much IPA you are talking about - all of the different additives in acrylic emulsions have different solubilities, and a lot of water-solublwe compounds are quite sensitive to it. 3-5% may be ok, but higher may cause problems - this is why so many companies selling their own thinners
This is a great video and agrees almost 100% with my own research. Except one thing. You suggest, that so called "water based acrylics" like Vallejo, Ammo Mig or AK 3Gen are just regular acrylics, similar to Tamyia X, only with more water content and some additives. I think they are not. Such difference in water amount or other components wouldn't explain their distinctive properties. They would be polyvinyl paints where the main binder is polyvinyl acetate (PVA). It causes them to be rather soluble than miscible in water before dry. They don't like pure acrylic solvents, even those miscible with water. They give elastic skin-like layer after drying compared to shell-like cover of acrylics. And after curing they are more resistant to mild solvents compared to acrylic resins. Which makes them better for brush painting as fresh layer of paints doesn't dissolve previous layers. Manufacturers call them 'acrylics' because customers get used to the term and understand acrylics as water-based, eco-friendly and so on. I think they may contain some addition of alcohol dissolved acrylic resins to improve durability etc, but they are technically vinyl paints.
Sorry, I don't believe you are correct in this, they're NOT polyvinyl as the MSDS usually call out their acrylic content (though not always, depending on manufacturer)
Could you please provide a link to MSDS for one of those 'water based ' acrylics? I couldn't find any. Moreover, either acrylic, or PVA resin are neutral substances so manufacturers don't need to include them on the ingredient list.
@@henrypaget8555 I have seen one in the past but tbh I have no idea where from or what it was! That being said, you're quite right that vinyl and acrylic polymers are not classed as "cause for concern", so any declaration is voluntary, and hence any company is likely going to try to keep any mixture they make as confidential. However, in the EU at least, a company can't label something as being that if it isn't. The paint would HAVE to contain acrylic resin or emulsion of some sort to be able to be labelled as such. Now it's technically possible that a vinyl co-polymer could also be present, but I highly doubt it since this affects the long-term water stability of the finish, and that would be a significant market disadvantage. The short term curing properties of a paint can absolutely be explained by formulation and additive differences without needing to be a completely different polymer base, so I think unless you have evidence to the contrary, we should consider anything labelled as an acrylic as an acrylic.
I tend to enjoy acrylic paints more. Better for indoor use, plus they tendo have a greater color range. But I hace found it difficult to find a good thinner, usually I use either distilled water or matte medium.
Whether something is a paint or an ink is a bit ambiguous these days, but generally speaking an ink is more fluid and tends towards more transparent pigments, whereas a paint has a thicker body consistency. I think that paint and hobby companies have their own "rules" on when something is an ink rather than a paint, but I think the consistency is the one I'd point to - so an ink is a high-flow pigment dense fluid, whereas a paint is a lower-flow pigment-dense fluid. You can think a paint to ink-like consistency, but it's pigment density will drop in doing that.
Ok so if water based acrylic is a myth you need to tell that to Vallejo..it states on the bottle that it is indeed WATER based.., Pro Acryl and even Citadel are water based. I can keep going as there are many brands that also say they are water based. So basically what you are saying is that every company that says this is falsely describing their product....Water is a solvent...
@reefhog "acrylic paints are water based" his second statement..then he clearly says that both are completely false...they are not both completely false.
Yes, I kinda AM saying that. The paints are NOT "water-based", they're based on an Acrylic Emulsion. They say they are water-based so that lay-people understand what they're diluted with, which is water. The solvent is not the basis of the paint, I can also tell you 99% of American paint companies are mis-labelling their house paints too - they say they are Latex paints, when they have nothing to do with LAtex at all, they're Acrylic emulsions (in the UK we refer to the same paint as Emulsion) Guess what, just because a company says something, doesn't mean they are correct - sometimes they describe something "a bit wrong" due to convention, ease of understanding for the end user or just because their marketing department wants it that way.
@@MannsModelMoments Exactly. We colloquially refer to paints as water based, simply referring to washing up and thinning. Water based by literal definition would mean water was the main ingredient.
What are you talking about "low quality" images? The example you cited is an HD image - do you mean what it represents? If so, it's an image to represent a day of time - how else would you do it??
@@MannsModelMoments Maybe so, but you've either been on RU-vid too long or have zero sense of humour if you didn't spot all that as a pretty obvious joke. Ah, well....
@@Frank_Nemo .No I've a good sense of humour (which is why I asked initially if it WAS a joke), but I've also had a lot of toxic trolls make snide comments, so attempt to qualify before giving an actual response - as the second reply didn't seem to indicate it was a joke, hence my "serious" reply. Unfortunately there are a bunch of toxic people who love to troll, so I have to be a bit "territorial" as it were!
@@MannsModelMoments I dont use acrylics in any form nothing that mixes with water ever The Laquers i use are hot, u can`t mix with water, anything that mixes with water dos`nt stick to plastic. How do know this well I am a NACE certified corrosion engineer who has experience of more paints u can shake a stick at But your video was decent
@@Jeff-cv4qn Once again, you're just not getting it - and you obviously haven't watched the video because you're spouting exactly the sort of rubbish a lot of idiots in the hobby do. Being Acrylic doesn't make a paint water soluble - the more you speak the more foolish you're appearing. The lacquers you use will be acrylics - try reading the bottle.
@@MannsModelMoments Cellulose, enamels and 2 pack are not acrylic and they are the only paints I use because i prefer them to water mixable paints I did watch your video and I thought u did a good job.
@@Jeff-cv4qn well you didn't specify which lacquers and given that nitrocellulose based paints are generally completely unsuitable for most modellers. and have been almost completely replaced by acrylic ones, you remain firmly in the minority. The point stands that you excludied acrylics as "water soluble" paints when that's exactly what the video explains they aren't!