I have been fumbling along with airbrushing with water-based acrylics for a while and need some advice on best methods for measuring how much paint to use and how much to dilute that measured amount. For example, let’s say I want to paint a diesel shell (HO)- what quantity of paint would be sufficient to do the job, Could (or should) I preserve the remainder, or remix a new batch if a second coat is needed? Cedarwoodron
I mix a fresh batch each time i paint, What I do is use some sarringes (spelling?) That I get from a nurse that Is a friend of mine. they have nice markings on them that makes it easy to suck the amount of paint out of my paint bottles and the same with my thinner. (I was told to mix to the consisty of milk.) I write the ratio of paint and thinner I have used on a scrap of paper that way if in need more paint it’s easy to mix up another batch… I hope that make sense or helps.
Thayne.
I use inexpensive pipettes that can be found at art supply places. ( A pipette is a plastic tube about 8 inches long with a small squeeze bulb on the top. Squeeze the bulb, stick the end of the tube in the paint and release the bulb to suck up paint (or water or alcohol or whatever is being used to thin the paint.)) I use a waterproof marker to mark the pipette in 1 inch increments. So 5 inches of paint and 1 inch of water make for a 20% dilution, which is what Polly Scale recommends, I think.
I make fresh mixes for each paint job.
As far as how much to mix for a given job - that’s hard to say, but it is something you learn from experience. I honestly can’t say how much I mix for a given job. It’s easier to toss a little extra than to make more. I generally use the color cup as opposed to the jar, and on occasion I have seen I was getting low so I quickly add more paint and thinner to the cup and mix it up quick with my custom-made-all-expense-spared paint stirrer, which is a piece of 14 guage copper wire with a small loop in the end.
George V.
FYI: it’s syringe
I use paper soda straws to mix small amounts of paint. Just dip it, cover the open top end with your finger, and the liquid will stay in the straw until you remove your finger.
I too use syringes for measuring paint and thinner. They’ve already got millilitre markings on them so it’s easy to measure. One trick I use is to suck up more paint or thinner than I want then squirt the excess back into the bottle until it’s down to the mark I want on the syringe. It’s easier than trying to suck up a precise amount.
I mix the paint/thinner right in a jar that fits my airbrush and have found that the paint manufacturer’s web site is the best place to find info on thinning any particular brand of paint. Paint-to-thinner ratios are pretty easy to judge by-eye in a straight-sided clear container.
I’m not sure how you’d determine the amount of paint needed for a single item, as I don’t usually paint unless I have sufficient work to make it worth my while - usually four or five items, but often 20-40. Depending on how often you paint (using colours that you’ve previously mixed and thinned) but you should get two or three weeks of shelf life from water-based paints that have been thinned for airbrushing. Lacquer-based paints that have been thinned generally seem to have a long shelf life, often measured in months, but for both types, the brand of paint, method of storage, and, often, the colour will have an effect on how long the paint will remain useable. When in doubt, mix and thin a fresh batch.
Wayne
I use a Badger 200NH single action air brush and Polly Scale paints. I use them ‘as is’ right out of the bottle. (I have the jar adapters and just screw them on the jar and paint.) I mix the paint up with a spin paint mixer from Micro-Mark. Pressure is usually about 35 psi.
So far so good.
I’ve actually found that you don’t really need to measure the paint / thinner ratio. For acrylics, you just need a little thinner in the color cup. For enamels maybe a 1:2 ratio of thinner to paint will work. The thing to remember is that you can always adjust the air pressure to balance out the consistency of the paint. Thin paint will spray well at 15 psi; thicker paint in the low 20s. So if you don’t get it exactly right you can always fiddle with the air pressure to compensate. Also, make sure to put the thinner in the color cup first otherwise the undiluted paint will clog the nozzle.
In terms of amount of paint, just guess and if you have too much, you can always put the rest back in the paint bottle. Even though the paint you are putting back in is a bit thinner than the paint in the bottle, the latter dries out over time so it all balances out in the end.
Based on what these responses tell me, I could elect to thoroughly mix the Polly Scale water-based paint in it’s original jar and use the adapter top to spray from or do a little bit of diluting, but less than what the jar instructions say and still get a decent quality of coverage. I have already available the separate jars with the feeder attachment and feel more comfortable with the original or those jars, as opposed to the color cup, which I fear will spill before I get the job done right. Thanks fir the feedback. I will experiment with all the tips and hope that an artist’s muse will guide my paint sprayer! Cedarwoodron