reconstituting dried acrylic paint

[John Allen]

Have many bottles of model shipway paints that have dried up. I have used a Dremel and bit to break the paint down add water and bring it back, this is a tedious process. Today I took a bottle of red that was totally dried up. Put a small amount of water in it and put in microwave for 10 seconds. It did not distort the shipway bottle which is a heavy plastic and paint softened enough to stir with a stir stick. That being said This may be a stupid idea, not knowing the chemical nature of the latex paint and or any residue left in microware.

Therefore moi being a dumb soul when it comes to chemistry and all the little molecules and atoms flying around what is the danger if any.

[Jaager]

John,

 

I have zero experience acrylic paint, but I think there are two major classes of color coatings:  paint and washes.

A wash - pigment in a solvent.  The wash applied, the solvent evaporates, the pigment just sits on the surface.  A dried up can of wash just needs more solvent to reconstitute it.

An applied pigment has nothing to hold it on the surface if exposed to external forces - rain,  splash, abrassion,...

A paint is pigment, a binder, and a solvent.   Paint applied,  the solvent evaporates,  the binder undergoes a chemical reaction as exposure to Oxygen increases.  A larger, more complex polymer is formed.  It sticks to the surface and keeps the pigment in place.

 

 

I think that dried acrylic has a different chemistry.  You may be able to mechanically shatter the plastic of the polymerized binder, but it will not work as a binder when this new gemisch is applied as a paint, even if you can make the mess into small enough bits to suspend in the solvent.  It is now a wash.

 

Another factor,  pigments have interesting chemical names,  cadmium, titanium,  heavy metal type elements.  Not really healthy to breathe.  Thinking about it, it probably a good idea to wear a mask or work in a hood when sanding dried paint.

 

If you are paid a reasonable wage,  the time spent recovering the dried mess,  even if it were not a fruitless exercise, is likely more costly than new paint.

[Bob Cleek]

Free yourselves from the tyranny of "model paints." They are a huge rip-off when you consider what the paint costs to make, package, and ship. In most instances, I expect the manufacturer's cost of the bottle is more than the cost of the paint and, yes, those partially used little bottles dry out before you get around to using them up.

 

There's a radical alternative. It takes a bit of a learning curve to master, but the basics are easily acquired and, for ship modeling purposes, the basics are pretty much all you need to know unless you want to get into really sophisticated weathering techniques which are, themselves, easier this "old fashioned" way. Do as the fine artists of old did. Mix your own paints. You will have complete flexibility in terms of consistency, flow, drying time, color and hue and save a considerable amount of money otherwise wasted on dried up little jars of what they pass off as paint these days. You won't have to grind your own pigments and mull them, though. That's done for us when commercially produced artists' oils, turpentine, and a bit of Japan drier are used. With the limited pallete we use in ship modeling, you won't need to buy a lot of different colors, either.

 

Here's all you need to know: https://figurementors.com/limitted-palette/the-science-of-oil-paints-with-kyle-kolbe/

[John Allen]

That's an eye opener, thanks for the link.

 

[mtaylor]

John,

I'm curious.  Did you try the "reconstituted" paint?  

[Bob Cleek]

19 hours ago, mtaylor said:

John,

I'm curious.  Did you try the "reconstituted" paint?  

I'd tend to think it wouldn't work because, even if you ground up the hardened paint very finely, you'd have a bunch of dried binder mixed in with the pigment and when you tried to reconstitute that,  you'd run into problems. Once an oil binder polymerizes, or an acrylic binder cures, I don't think that process can be reversed.

[mtaylor]

I had a feeling that you're right, Bob.  But I thought I'd ask anyway.

[Charles Green]

Bob Cleek/Painting Book:

 At the end of the article you cited, an up-coming book by Kyle Kolbe, "Artists Oil Color Miniature Painting Handbook" is mentioned.  Did this book make it to print?  I haven't been able to locate it.

[wefalck]

We had this discussion at other places I think already.

 

Acrylic paints are dispersions of acrylic acid molecules in water (possibly alcohol) with finely ground pigments suspended in them. The curing of these paints happens in two stages or perhaps parallel processes: the solvent, the water evaporates, and the molecules begin to intertwine, trapping the pigment in between. The first process happens within minutes (when spray-painting) or an hour or so (when brush-painting), while the latter process will continue for days or even a week or two. It is not possible to redissolve acrylic paints without breaking up the molecules, i.e. destroying the binder. You can, of course, grind up the dried paint, but all you get is a slurry, but not a paint. You would need to really finely grind it and then add new binder, i.e. acrylic acid solution - but this is not really worth the effort und almost certainly will not yield a satisfactory product.

 

The same considerations apply to dried out oil-paints. Here the binder is lineseed oil and the curing process an oxidation induced by short-wave radiation, namely UV-light. Once oxidised, the process cannot be really reverted. Again, if you grind up the paint, you will end up with a slurry and would need to add more lineseed oil as fresh binder.

 

Not sure that making your own paints from scratch is really an efficient process. Of course the painters of old did this, but then jumped onto the confectioned paints, as soon as these became available around the middle of the 19th century (facilitating the open-air painting of the School of Barbizon and somewhat later of the Expressionists). You are not likely to arrive at the same level of homogeneity and dispersion of commercial products. The resulting product may be ok for painting by brush of small areas, but probably nor for painting larger surfaces, let alone for spray-painting. This is one reason why the technique of painting, sanding, painting, sanding, and finally polishing was developed.

[Bob Cleek]

On 8/14/2020 at 8:04 AM, Charles Green said:

Bob Cleek/Painting Book:

 At the end of the article you cited, an up-coming book by Kyle Kolbe, "Artists Oil Color Miniature Painting Handbook" is mentioned.  Did this book make it to print?  I haven't been able to locate it.

All I can find are references to Kolbe's "forthcoming" book. I guess it hasn't come forth yet. His blog piece (link above) is widely cited, however, and I found it pretty comprehensive. 

[Roger Pellett]

A number of now old timers, Rob Napier and Eric Ronnberg among them advocated custom mixing of paint from tubes of artist’s colors.  Ronnberg in particular used acrylic artist’s colors to paint his collection of large scale New England fishing Schooner models, now in the Mystic Seaport Collection.  During the 2015 NRG Conference we saw these models in Mystic’s storage area and they looked like they were freshly painted.

 

I tried this technique to paint my scratch built longboat model.  I mixed colors from acrylic artist’s pigments, added some acrylic matt medium and thinned them with water.  They sprayed beautifully with my Badger 350 airbrush.  When I was satisfied with the results, I overcoated with a light coat of Dulcote.  

 

I will paint my next model the same way.

 

Roger

[John Allen]

On 8/11/2020 at 9:50 PM, mtaylor said:

I'm curious.  Did you try the "reconstituted" paint?  

Hello Mark,

Been out of the loop for a while. Sybile wife of 52 years passed May 8th. I am just be beginning to deal with it. Years ago she was an ACLS Paramedic and I a Marine Policeman. Little Bio Hurricane Frederick took out Dauphin Island Bridge. We went on calls together, her medicals my rescues. for a 3 year period. this was before life flight so transport times were between 2 to 3 hours depending on weather by boat and C.G. Training choppers if training in the area. We were tied to the hip, and as close as 2 people could be.

Apologize to all know this was not the area to post. 

 

To the paints, I have reconstituted semi dried (the totally dried hard as a rock I did not attempt) they were soft enough to break down, added very little water and mixed with a drill bit on a Dremel. They seemed pretty thick (totally smooth no chunks or hard pieces.) even had to add a little water to thin. That being said I had used a couple of colors on the interior of the Hunley I am trying to destroy. They seem okay when dry, colors seemed as bright as a new bottle, whether they last who knows. Having shallow pockets I'm cheap. I do not have the skillset at this time to expend dollars on tube acrylics and mix colors I would and up with a model looking like a Rat Rod. So I'll muddle along until someone takes the word model out of acrylics and the price and packaging becomes reasonable.

[bruce d]

John, I am so sorry to hear of your loss.

[Roger Pellett]

John,

 

i’m sorry To hear about the loss of your dear wife Sylbie.  From your earlier posts, it seemed like the two of you enjoyed many adventures together such as “the snake in the bedroom story”  May these memories be a blessing to you.

 

Best wishes

 

Roger

[Canute]

John, my condolences, brother.

[JeffT]

Sorry to hear about your loss. My condolences.

[mtaylor]

John,  I'm saddened to hear of your loss.  As Roger said, hold the good memories, they are a blessing.

[Jack12477]

John, sorry to learn of your loss. My condolences also