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preshading and lifecolour
lespauljames
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England - South West, United Kingdom
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Posted: Sunday, November 06, 2016 - 03:40 AM UTC
Hey all !
I'm having a bit of trouble with my preshading. I cant seem to get a consistent finish. I usually use lifecolour. I seem to be getting sub par atomization with the paint as when I try to build up transparent layers it looks a bit speckled. Spraying about 25-30psi. I seem to get a lot of trouble with inconsistent spraying with these at lower pressures also. When trying for fine detail I get the spray tapering out. Is that tip dry?
Scrodes
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Ontario, Canada
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Posted: Sunday, November 06, 2016 - 04:09 AM UTC
This is probably hard to answer without photos of what the paint looks like.


It could be dry tip. How much are you thinning the paint? Air pressure is usually less important than the ratio of paint to thinner as long as you're not pooling paint.


From what you wrote, I think it actually sounds like you're getting an orange-peel type of finish, no? If you are, it's because your paint is too thick. You want it thinned to about the consistency of milk - it should run down the side of the cup,trailing some of the colour.
lespauljames
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England - South West, United Kingdom
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Posted: Sunday, November 06, 2016 - 05:59 AM UTC
Matt, its not orange peel my paint is very thin, I use 20% flow improver to slightly slow the drying time. I don't have pictures as yet but I can do some tests over the next few days. I could say my paint consistancy issimilar to alclad out of the bottle.
thegirl
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Alberta, Canada
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Posted: Wednesday, November 09, 2016 - 06:51 AM UTC
What are you using for thinner and your needle size James ?

To get excellent atomization of the paint you need the right thinner to break down the paint particles and your needle sizes matters as well along with air pressure .



Terri

lespauljames
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England - South West, United Kingdom
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Posted: Wednesday, November 09, 2016 - 04:41 PM UTC
Hey Terri, iwata hpb, so a 0.2, when I thin lifecolour I use water and flow improver. I think I may have thinned the paint too much (I thin the jars ready for spraying). As rlm02 grau had a similar problem but when I used a fresh jar I don't think I thinned it as much and it went down better.
as for air pressure I used to spray everything at the lowest setting my compressor could offer but as of late I have had to to use higher. 15-20 psi. As I think my needle or nozzle has a minor defect and lower pressures tend to splatter now when they didn't previously.
thegirl
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Alberta, Canada
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Posted: Thursday, November 10, 2016 - 06:13 AM UTC
Hi James ,

Stop using water for airbrushing if you want excellent atomization of the paint . Water doesn't break down the pigments or ( melt the paint particles ) enough . Not saying you're doing something wrong . But having worked in an auto body the artist the can in to airbrush graphics and such I asked them a lot of questions .

When paint starts to misbehave it's the type of thinner you are using . Even though acrylic can be cleaned up with water doesn't mean that it can be used as a thinner .

Type of airbrush also does matter . Any airbrush can spray paint and this comes down to your needle size . Most airbrushes on the market have the standard sizes . .2mm right up to .5mm Not small enough . The finer the needle the better atomization of the paint .

I use A Paasche Eagle Talon with a .66mm needle and run my pressure between 15 and 20 psi 25 for natural metal .
You need the higher pressure so it pushes the paint faster along the tip forcing the paint break down into smaller atoms .


I haven't used Lifecolor paints but I do know they are water based . If they have their own thinner they I recommend you give it a try . Ask around and see what other folks are using . If you are set on using water then use distilled water . Don't use tap water or water with minerals in it . These interact with paint charging it's behavior and it's not consistent .

I use Tamiya paints , but I only thin them with their own lacquer thinner . I don't use their X20-A for airbrushing . Only when I hand paint . Tamiya isn't a water base acrylic . It's cellous . Alcohol gums it up . Vallejo model air has work it's way on my paint rack and here I use their brand of airbrush thinner . I never never had any issues or troubles since I myself stop using water .



Terri

Joel_W
Staff MemberAssociate Editor
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Posted: Friday, November 11, 2016 - 12:01 AM UTC
James,
I've experimented with Lifecolor paints for the last 6 months, and have just about given up on them for anything but general wide pattern airbrushing. I only used their proprietary thinner. As for thinning their paints, which are on the thin side, I generally used for light colors 2:1 and dark colors 1:1.

As for using flow enhancers, you're using way to much, as about 10% is the max. 2-3 drops is all you really need per 3/4 full airbrush cup. You're also using it for the wrong purpose. Flow Enhancers are exactly that, they enhance the flow as would a few drops of dishwashing liquid by breaking down surface tension, they don't stop the drying time of the paint medium.

To slow down the effective drying time of the paint, you need to use a Retarder. Again, a few drops per cup is all that you need.

The use of either medium or both will have the effect on acrylic paints behaving more like enamel oil paint.

when I'm working in close for detailing or tight patterns, I'm within a few inches of the model surface. I lower the flow rate of the compressor to 12-14 psi. That's the psi when the airbrush is shooting paint, not when it's in the off position, which is a meaningless figure. The only thing that figure is good for is after a while you'll know what the drop in psi is on your system, so you can preset it. There is just to many variables to have the same drop from one system to another.

What I continually found with the Lifecolor paints when I wanted to do detail/close up painting is that at low pressure they started to spurt as if the airbrush was running out of paint. Turning up the psi and maintaining the close distance caused the paint to "splash". Variations of thinning ratios and psi adjustments never led to a working formula for a full paint session without constant issues.

And yes, tip drying especially when I paused for a min or two was a constant issue.

I went back to my old friends: Tamiya Acrylics, and Model Master enamels (just for certain applications). I thin Tamiya acrylics with their Yellow cap Lacquer based thinner, and can draw the thinnest of lines without any issues. When I do that type of work, I do add 2-3 drops of Enhancer. I don't use a retarder at all.

BTW, their X-20A is nothing more then equal parts ISO to distilled water and 10% Enhancer. That's as per Bobby Waldron.

Model Master enamels I thin with their Red can Universal Mineral Spirits.

Joel