Once again I come to you with my model trainman’s hat in hand and a question raging around in my head. I have decided that it is time to take the plunge and to start weathering my rolling stock and what better place then my recently aquired, gently used cars.
As is the case with so many of us in these times, money is most certainly an issue, so I have purchased good quality acrylic paints of some basic colors, and plan to blend them to create my desired shades. Rather then ‘wasting’ the entire bottle of paint, I thought I would measure out small amounts of the component colors and store the custom blend in small plastic bottles that we have on hand. Since my layout is in N scale, the amounts of paint that I need are quite small, so I thought that a medicine dropper would be the perfect way to get an exact, replicatable blend of colors. The problem is that the moment I drew the paint into the medicine dropper it instantly coagulated into a rubbery blob that would not come out of the medicine dropper. The only way to move it, and how I found that it was a rubbery blob was using a toothpick and narrowed wooden skewer to pull it out with. So, the questions are:
As a point of curiousity, does anyone have any ideas of why this happened? Is it likely to occur everytime I try to use a medicine dropper to measure out a precise quantity of paint?
What methods do you,more experienced/skilled modeller use to measure out a precise amount of paint so that the same amounts can be repeated in order to replicatea particular shade?
In a related, but separate question. Based on articles I have read in Model Railroader, and in threads on these forums, I also tried to dilute a small amount of my acryllic paint with 70% alcohol. But, as soon as the paint touched the alcohol it coagulated into a rubbery mess on my brush. Is this common? How do you get around it?
Not sure why your paint should coagulate going into the dropper unless it was not well mixed or old paint. Hope someone else can shed a little light on that.
As for diluting acrylics, I have seen some posts saying they have used distilled water, Tap water can conetain minerals and other contaminatants that will react with the paint. Don’t recall anyone saying they used alchol, but memories can fail or I just might not have read the post.
Sounds like you have old paint. Not sure why that is happening when the paint touches your brush either.
I use artist’s quality tube acrylic paints and use Acrylic Flow Medium to mix it with to make it flow better, smoother and not gob into corners, dry out or coagulate, etc. It comes in a large clear bottle about 3 inches tall and should be sold where ever Artists tube acrylics are sold.
{Don’t know how it will react with cheapy acrylics though or how it works in an airbrush.}
I’m not sure what you mean by “good quality acrylic paints” ? What are they exactly? Are you sure they are water-based acrylics? It does sound like those paints are either old or being contaminated.
Many of us use the inexpensive (50-80 cents a bottle) craft paints available at Walmart, they are good quality and work very well for a miriad of MR uses including weathering. Measuring exact amounts of paint is not critical for weathering. All weathering and aging is not the same. Consider getting some chalks or weathering powders (get a Micromark catalog or visit them on line - micromark.com )
As for thinner, get a bottle of acrylic thinner at the paint section of your hobby shop. When that bottle is empty, fill it with an 80/20 mix of water/70% isopropl alcohol. Unless you have real hard water and/or high calcium content, you can use tap water, otherwise use distilled water which you can buy in jugs at your supermarket.
Whenever I go to McDonalds, I grab a handfull or two of the little plastic condiment cups they keep over by the ketchup, they make great little mixing cups. If I’m handbrushing paint on the model, I’ll just pour a few drops straight from the bottle(s) into the cup. To add a drop of another color, I use coffee stirrer sticks to transfer a drop at a time and then use it to mix the paint. For washes add a couple of drops of paint and then add 90% more of water. You have to experiment a bit to get the hang of weathering and don’t start with your nice newly aquired cars, start with some cheapos.
Thank you for your quick responses. By quality acrylic paints, I meant that we purchased it at an artist’s store, where I was told that it is a “quality acryllic” usable for everything from professional artist’s work to crafts. And, it is water based and non-toxic. So, I am guessing that I was sold a bottle of old stock! Is there any way to tell, other then to ask and hope to get an honest answer from the staff? I have to confess that I didn’t realize paint had an ‘expiration’ date. I thought if it is still wet, it is still paint! [:$]
So, if my paint wasn’t ‘bad’, a medicine dropper would work? I am not so much concerned about getting the colors exactly the same on the weather effects, but later when I get more practice with a brush and start to paint my rolling stock, railroad buildings, etc.
As for diluting with alcohol, it is late on a Sunday night, but if my memory serves it was referenced in a discussion about adding grout lines. My thought was that by diluting with alcohol, the pigment would be more dispersed, leaving a thinner layer and it would dry more quickly then if I used water.
So, I ask yet another question (please forgive my new guy ignorance), but could people offer opinions on wether I should dilute with water or alcohol, or are there specific times where one is used and other times the other?
You still didn’t mention the brand of paint, if it was Apple Barrel or Creamcoat in a bottle, it should be fine. The reason we suspect the age of the paint is because we have seen acrylics behave that way when they have been sitting on the shelf too long. The plastic bottles aren’t completely air proof and can draw in air by osmosis through the plastic bottles. The other possibilty I mentioned was contamination with solvent thinners like laquer thinner or mineral spirits, these can also turn acrylics into a gummy mess.
There’s really no reason to use a medicine dropper as acrylic color don’t stay consistent, they’re slightly different from bottle to bottle and everytime you open the bottle, more air gets in and also changes the shade (darkens). But if you want to use one, that’s fine, just make sure it’s clean and and solvents you use (if you use them) to clean it are completely dry.
You do not need to mix your own RR colors as Polyscale and Modelflex offer virtually all the RR colors.
I am not in favor of using staight alcohol to dilute the paints. It makes the paint dry too fast and if you’re hand brushing, it can cause the paint to gum up the brush. You only need enough alcohol to help the paint flow, use the formular I suggested in my earlier post. These are water-based paints and designed to be thinned with water.
Thank you Modelmaker. I confess to being very ignorant on the issue of paints, though you have likely already guessed that!
The brand recommended by the artist supply store is Americana Acrylic paint. The lady at the store said she uses it, and that it is very good. Their website describes it as “an all-purpose, premium quality acrylic paint used for decorative painting, home decor, and general craft painting projects. Americana is water-based, non-toxic and has a matte finish that can be varnished to create various sheens. This paint can be used on almost any surface”. Sounded good to me!
I didn’t realize about the shade of the color varying over time in the bottle, let alone each time I open it up. So, what would you recommend as the best way to take a controlled amount out of the bottle? There is a little flip top lid, but the paint doesn’t drip from this little hole, so much as ooze out, and all over the lid of the bottle. It makes quite a mess, and wastes a great deal of paint. But, I do wonder if there may have been something contaminating the glass of the medicine dropper. My wife purchased a few at Wal-Mart for little more then pennies each. Since they are medicine droppers, we thought that there would be no need for me to pre-clean them!
As for cleaning solvents, the only thing that I use is water. That is why I am going with acrylic paints only, and not doing any spraying due to a variety of health concerns.
Is the material that you recommended to assist with paint flow very expensive? I will heed your advice regarding the use of alcohol as a thinner, and stick with the commercial blend, and then replace it with the formula you recommended.
Water {distilled would be best} IS good for thinning water-based paints like acrylics.
I would still look into aquiring and trying a bottle of Acrylic Flow Medium in the better artists paint sections and see how that works for your purposes. It should work with any acrylic paint and wont dry to quickly and/or evaporate too quickly.
I would still use an dropper to “measure out” your paints and dilutions {be sure to clearly write down amounts so you can duplicate it later.}
Also there is a battery operated mini paint stirer available at hobby shops I would invest in to thoroughly mix paints.
The big question is the viscosity of the paint you have! If it is too thick it is almost impossible to use a pipette (medicine dropper), I would recommend that you dilute the paint you will use to a consistency of buttermilk as there is no need to have “one shot coverage” when weathering.
I agree with the last two posters. Also, if the paint is too thick for the medicine dropper, you could use a straw as a pipet. I guess I’m a bit lazy, I’m a custom painter and mix paints all the time, so in general I just pour the paint directly from the bottles into a plastic cup (mentioned in my first post). If I just need to add a drop or two I use a wooden coffee stirrer that I dip in the paint bottle and then drop a drop at a time into the cup and there’s nothing to clean up.
When I switched to acrylics (almost 10 years ago), I bought a couple bottles of ModelMaster (Testors) Acrylic thinner, (see your local Model Train or R/C model shop), which worked fine. When they were empty I refilled them with 80% water and 20%- 70% Isopropl Alcohol (98 cents at your local drug store). I’m still using the same bottles. The 20% alcohol helps cut surface tension and facilitates paint flow. People will recommend other products for enhancing paint flow, but I’ve found that my mix of water and alcohol works just fine and it’s cheap.
The recommendation of a buttermilk consistency for hand panting is good. Half "n Half to light cream is another comparison if you don’t drink buttermilk! For spraying with an airbrush, you want to thin down to a consistency of 2% milk to whole milk.
For weathering, you are likey to need to use washes more than straight paint. A wash is usually about 10% paint and 90% thinner. The pigment will collect in the nooks and crannies. This is built up in successive layers until the desired effect is achieved.
Thank you again for the wonderful information and help.
Modelmaker51 I am unable to get to a LHS to purchase any Acrylic thinner, but I do have the Isopropyl Alcohol and spare containers of various sizes, so I am planning to mix up a batch for myself. But, I have two more dumb questions to ask. How much Acrylic thinner do you add per volume of paint? And, do you add the thinner to the stock bottle of paint, or to the amount of paint you have set out for a particular painting job?