Mr color paints

[chrisonord]

I recently bought a pot of Mr Color RLM Grey black in what I thought was matt. Heard good reviews about Mr Color stuff so thought yeah. Anyhow. I tried to thin it to put through the airbrush, it just separated from the thinner and gunked up the airbrush, big time. I had to use cellulose thinners on it. Also it is semi gloss that had been sent to me not the matt, which I suppose isn't too much of a problem. Also, it stinks as bad if not worse than cellulose thinners, seriously it is nasty. Does anyone know what it is made from as it certainly isn't Acrylic that's for sure.

[jcf]

The Mr. Color paints are an acrylic-lacquer, an acrylic resin base dissolved in a "hot" solvent carrier made up various high VOC butanones etc., they are not water-based. The word acrylic refers to the chemical make-up of the resin that forms the paint film, it has nothing to do with water.
Aqueos Hobby Color is the GSI-Creos "water-based" acrylic line.

The term "water-based acrylic" is itself misleading, the paint "base" is an acrylic resin in a carrier of water and various other things, alcohols are common.

The carrier in a paint and it's solvent are generally the same thing and you only want to thin the paint with the
same thing.

However there are exceptions i.e. the Aqueous Hobby Color can be thinned using the thinner for the Mr. Color "lacquers" because the carrier of the "water based" paint is a combination of various alcohols, glycols and esters, all of which are chemically friendly with the hot solvents used in the lacquers also the acrylic resin base and the pigments are the same. However the lacquers cannot be thinned with water or the Aqueous Hobby Color thinner, it's a one-way street. The same thing can be done with Tamiya "water-based" acrylics and lacquers. BTW Tamiya also has a line of alkyd enamels.

As an aside "cellulose" lacquers fell by the wayside for most uses a long time ago being replaced by synthetic lacquers, originally phenolic and then acrylic. They were the standard in autobody paint in factories for a long time before being displaced by the water suspenion systems due to environmental concerns. However they are still the most common in autobody repair. The majority of spray paints, even those marketed as "enamel", are synthetic lacquers of various sorts.

The reason that acrylic resin based paints can be water thinned or hot solvent thinned is down to solution vs. suspension. In a hot solvent lacquer the resin is dissolved in the carrier and the paint film forms as the solvents evaporate. The paint film can be dissolved by its thinner. In the case of the water thinned paint the resin is in suspension as extremely small globules that adhere to each other and form the paint film as the "water" evaporates, there is also an element of a chemical shift during curing which is why you can't remove dried water-based acrylic with water. Once the water is gone the paint film is no longer soluble with just water. 

As to the finish, neither the Mr. Color nor the Tamiya lacquers are "dead matte", they all have varying degrees of luster, which is one of the reasons they recommend adding small amounts of their flatting agents to the paint prior to use, the idea being that you can adjust the level of matte to your own requirements.

[Rick Lowe]

Just don't overdo the flatting agent - it can make the whole paintjob look white and chalky.
I Know This Now.
Also don't leave a freshly-sprayed model in a cold garage overnight... 

[chrisonord]

I think I will be putting it in the box of no return as I really don't like using the stuff.

[zenrat]

Thanks for the lesson Jon.
Clear, plain english labelling on packaging would help.

[PR19_Kit]

Clear, plain english labelling on packaging would help.

Now don't be silly Fred, that would mean they'd limit their sales to people who actually WANTED their product. 

[jcf]

Thanks for the lesson Jon.
Clear, plain english labelling on packaging would help.

It's one of those things that's decades old, at some point somebody or other started referring
to water-thinned/water-borne acrylic/polyurethane varnishes/paints, and acrylic latex paints, as
water-based and it carried over into general usage. It's not going to change especially as the
"water-based" products are seen as being greener, which they aren't really. Sure they don't use
high VOC organic hydrocarbon solvents, but they're just as much a product of the petrochemical
industry. Ironically the main ingredient of the polyester alkyd resin used in most oil-based paints
is primarily soybean oil. Other oils like rapeseed oil are used and linseed oil is still used for higher end
products.
Fish oil was also used in the early 20th century, especially during WWI, because of plant oil shortages.
Yes, the paint did end up smelling slightly fishy and the resin colour shifted with exposure to UV, it
was really bad with white and light colours as they became very yellow, very quickly.

The figure painters who use artist's oil paints thinned with real turpentine can be said to be the
greenest modellers because the paint is pigment milled into linseed oil and the turpentine is
produced from pine trees. All hail the plant-based modellers.
🤣

[zenrat]

...The figure painters who use artist's oil paints thinned with real turpentine can be said to be the
greenest modellers because the paint is pigment milled into linseed oil and the turpentine is
produced from pine trees. All hail the plant-based modellers.
🤣

What are the models themselves made from though?
🤔

[jcf]

...The figure painters who use artist's oil paints thinned with real turpentine can be said to be the
greenest modellers because the paint is pigment milled into linseed oil and the turpentine is
produced from pine trees. All hail the plant-based modellers.
🤣

What are the models themselves made from though?
🤔

Cast or printed resin, printed filament, old school is white metal (lead in the oldest - yay, it's recyclable 🤣).
Some of the filament types used in printing are plant-based.

Neil is the greenest modeller you'll ever meet, his computer and 3-D printer are solar powered,
he only uses plant-based filament to print his figures, only paints them with oil-paints using
oil expressed from flax-seeds (linseed oil) he grows himself with pigments created from
natural sources (luckily for Neil he generally does figures from desert campaigns, the mineral
derived pigments are easy, he's still having trouble producing reds, blues and bright yellows)
and he only uses white shellac (shellac being a resin produced by the female lac bug) for varnish.
🤣

[Rick Lowe]

So 'Shellac' is derived from 'She-Lac Bug'? 

[Andrew Gorman]

It comes from bugs!  An interesting process:
https://www.youtube.com/watch?v=lQcQ0yuekZ0

[zenrat]

Neil's actions are commendable, if extreme.