Air Brush Questions

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Rocketmaniac

Well-Known Member
I've been playing around with my new hobby air compressor and I come up with a few questions for the artists here on TRF.

First let me tell you a little about what I have. The air compressor is from "Airbrush-DEPOT" and is model TC-20. Right now it is set on 60 psi.

The actual air brush is one I got off ebay a year or two ago. I don't remember the brand. I believe it is a single action. It is one of the ones with solid plastic case or frame. You can't dissemble it.

And finally the paint. It is just some ordinary house paint from Lowes. (It's the pink for my daughter's Barbie Rocket)

Questions?

1. How much water do you add to the paint to thin it?

2. What is a good air pressure to the set the compressor to?

3. How far from your work should you be holding the air brush?

What I found out this morning is everything seems to be work ok, but I am not getting much paint on the rocket. After a while, I cleaned everything up and ran water through the air brush. It seem like a good amount was coming out the nozzle.

One last note. The only other time I have used this air brush was few months ago when I tried to paint with some "canned air" I knocked over the can and after a few seconds of lots of air, the air flow pretty much stopped. I cleaned up the air brush but was unable to run water through it. (no air supply)

Thanks

Rocketmaniac

Well-Known Member
Here's a pic of the air compressor

Rocketmaniac

Well-Known Member
and a close up of the label

Rocketmaniac

Well-Known Member
and finally the air brush

limd21

Well-Known Member
Originally posted by Rocketmaniac

And finally the paint. It is just some ordinary house paint from Lowes. (It's the pink for my daughter's Barbie Rocket)

Questions?

1. How much water do you add to the paint to thin it?

2. What is a good air pressure to the set the compressor to?

3. How far from your work should you be holding the air brush?

What I found out this morning is everything seems to be work ok, but I am not getting much paint on the rocket. After a while, I cleaned everything up and ran water through the air brush. It seem like a good amount was coming out the nozzle.

As one who regularly shoots house paint through an airbrush with great success, I'll chime in with my thoughts.

Most latex housepaint is pretty thick from the can, so it needs to be thinned quite a bit to get to a consistency that works with an airbrush. The general rule of thumb is to thin it to the consistency of whole milk. That may require 60% (or more) thinner to 40% (or less) paint. In contrast, most paints found in hobby shops are much thinner in stock form and the ratios of thinner to paint are reversed. In reality, however, I personally choose to mix a bit thicker - more to the consistency of cream. Typically, this is about a 50/50 mix. To shoot a slightly thicker mix, a bit more air pressure and a more open nozzle setting is required. This type of mix and airbrush setting is great for rockets where you're trying to get broader coverage of larger areas. The plastic modeling guys like to do much more finely detailed work and shoot thinner paints at much lower pressures.

In any case, for shooting this setup I usually go with about 40psi. Higher pressures can work, but you need to keep the nozzle opened more otherwise you may get what is known in a/b circles as "tip dry" where the paint dries on its way out and can lead to clogging. With this 40psi setup, I usually shoot 8-10 inches away from the rocket. More distance for more pressure, less distance for less pressure.

For thinner, my favorite is regular windshield wiper fluid. It's basically mostly water with a bit of alcohol which I think helps to make for a smoother flow. Some modeling guys use straight alcohol, but I think that exacerbates the tip-dry problem.

Keeping the ab clean is really important. The orifices are small and are easily clogged with drying paint. So when you're done shooting (or taking a break between coats), be sure to at least shoot some thinner or water through the ab. A full breakdown cleaning is what I do once my painting is complete.

My ab for rockets is the old standby Paasche H single action. With the large #5 tip, It is excellent for shooting rockets - with spray coverage that is better than a spray can.

Stymye

Well-Known Member
generally the paint has to be very thin, and spray "around" 30 psi
I'm not familiar with your airbrush, does it come with different needles?

try setting it up with just water and see if you can get the spray pattern and coverage you want, than change to paint , you may have to thin it down ,
don't adjust the brush and just add thinner or water till you get a simmular pattern and note how thin the brush requires, also some paints will work much better if they are filtered

*edit-just read limids post, good info

Rocketmaniac

Well-Known Member
Originally posted by stymye
does it come with different needles?

Nope, just one needle. It's only a plain jane air brush. I know in time I will need to get a better air brush. But for now, I want to try and get this one working ok. (I'm a un-employed, full-time student right now)

I will try a little less air pressure and a little thinner paint. I will also try different thinners. ie windshield wiper fluid and alcohol

Thanks guys

Rocketmaniac

Well-Known Member
Originally posted by BobH48
Here is a link to a magazine article on airbrush techniques.
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Thanks Bob,

good article. I quickly read through it and found a picture of a bent needle tip. Looking at my airbrush, this is part of my problem..... I guess I need a new airbrush sooner than I have hoped..........

Rocketmaniac

Well-Known Member
Here's an update;

I just got my new airbrush. I got a Badget 200-NH. I paid $41.95 from https://www.dixieart.com/ Right now, all orders over$45 have free shipping. So I ordered a bottle of paint and got free shipping.

I am going to try it out after I get home from school today. (tue, thur are my easy days.... only one class)

Rocketmaniac

Well-Known Member
Ok guys,

I've just done my first real airbrush painting and I have some more questions. Here is what I did.

I got everything setup and mixing the paint (standard Acrylic Latex) with windshield wiper fluid. I did about a 50/50 mix. I tested the airbrush on a piece of plexi-glass and got the spray looking pretty good.

So then, I started in on painting the rocket (my upgraded estes 4" V-2) It looked pretty good, a little thinner that standard paint cans. After 5-6 minutes the spray volume started to go down (color, not air-flow). I looked at the paint jar and it was getting close to running out so I stopped and quickly re-filled it.

At this point it was hardly spray was getting real bad (color, not air-flow). I noticed that between the "guarded spray regulator" and the "needle" there was a build-up of paint. So I took the airbrush inside and took the front end apart and cleaned it up.

When I went back to paint, I got no paint. I still had a good flow of air, but no paint being sucked out of the paint jar. (the airbrush is bottom feed) After a few more minutes I shut everything off and came back inside. I now have the airbrush apart and soaking in water.

I was running the air compressor at about 38 psi.

Anyone got any ideas?

Stymye

Well-Known Member
what size needle , you want to use atleast a #3 needle
it should come out in volume like a good brand spraycan paint
if you have to thin it that much, it's not the right medium to paint a 4" Rocket.and you will have to crank up the pressure to keep it from sputtering... but that also can cause"tip dry"

If your using craft paint (or housepaint !) strain it thru a piece of pantyhose. but keep in mind, the pigment is not ground well enough to get the best results from an airbrush so you have to thin it down so much that the paint will run very easily.

also check the bottle /pick up tube.. for any blockage

just some possibilitys

moocrew

Well-Known Member
wow...A/B help eh?...wish I had seen this one earlier.
Trust me once you good A/B you'll never go back.
All give all the info. that I think will help you. If you ever need anyother help Aim me or email.

First off.
Does that compressor have a filter on the "out" or "in" line that anywhere?
If not...those help..also help with clogging. These aren't absolutely nessecary but good to have if you invest in a really nice A/B.

My second question..
Is the A/B you bought single or double action?

Alright for Airpressure I usualy work no higher than about 20-22 psi.
With my double action anything higher than that is just over doing it...and I'm not in a big enough hurry usually to have to really crank it up...not to mention it can cause stress on the brush.

I agree with styme about "filtering" your paint...chunks of paint can be a real pain. I usualy shake my paint for about 2 min. Then I thin (if needed) then I shake or mix again for about 2 min.
After awhile you'll get a hang for how much area you can cover with a certain thickness of paint and can mix all the needed paint BEFORE you start painting...stopping half way through usualy is a pain and happens just when you're really starting to get that nice glass smooth stroke going.

As far where you should hold the brush when you spray...There is no "set" distance. it varys really. If you're going full blast then back of the roc abit runs are a kick in the pants. Just play around with it on some card board or something till you get a feel.

hope I gave something a little different atleast.
good luck

_matt

Rocketmaniac

Well-Known Member
This is an update to what I did on Friday and to answer the questions.

Originally posted by stymye
what size needle , you want to use atleast a #3 needle

First, the needle size? The ad only said "medium" tip.

Originally posted by moocrew
First off.
Does that compressor have a filter on the "out" or "in" line that anywhere?
There is something, but it may only be a "water trap" The attached pic gives you an idea.

Originally posted by moocrew
My second question..
Is the A/B you bought single or double action?
The A/B is only a single action. I was thinking it would easier to learn on a single.

Now for what I did on Friday. First, I put the unit back together and tested it with water. It worked!!! Then I figured out that I had put the "trigger" in after putting the needle assemble in. The "trigger" has a slot in it that the needle runs through.

So, I put paint in the jar and started painting. It worked pretty good, but still clogged up after about one jar full (3/4oz)

I will try out cutting down the air pressure even more.

Thanks for all the help

Rocketmaniac

Well-Known Member
oops, forgot the picture....

moocrew

Well-Known Member
filter no filter either way anything helps and that does appear to be some type of filter or trap.
I'm not real sure why the brush keeps clogging. You've explained pretty much everything that you do before painting....and I honestly don't know why it would keep clogging..it doesn't make any sense. my only other Guess would be the Thinning.
I've never used w/w fluid. From what i hear its good to use. But i've never tried it. I might strat to think that mabey the paint and the thinner of choice are seperating slightly and causing clumps...or its just not mixed well enough..I really couldn't tell you.

1 more question though.
Are you mixing the thinner and paint IN the jar you use to paint with...( the can you attach to the brush)?
If so this could very well be causing clogs. The thick paint sticks to the sides and I don't care how well you mix it there is always something you just can't get mixed in with the thinner.
Just an idea.

-matt

Stymye

Well-Known Member
Randy , this may or may not pertain to your situation

I think the problem most people have is the tip size
for doing general spraying,see if you can get a large needle/tip. Most airbrushes come ready to spray plastic models and t-shirts, but will not spray a larger pattern very well,no matter how much you tweak the paint and air pressure.
the needles are usually in the 5-10 dollar range

I played with my airbrush for a long time but would never get good results, eventually I gave up on it because, I could get better results with a spray can. I would have small patterns work for example camo squiggles and making lightening bolts, fuzzy flames, fading ect..but couldn't get a nice even coverage on a body tube no matter how much I tried.I got tired of fighting with it so I tossed it in a drawer and left it there for over a year in frustration

I had completely forgot that my A/B came with different needles, so one day I thought I would try the biggest needle as a last ditch effort,, and it made all the difference in the world ! It was like night and day !
you don't have to thin the paint down so much(if any)
some paints will coagulate(sp) when you add too much water
people suggest adding alcohol , windshield fluids,windex to combat that problem, but thinning the paint so much often gives drab results regardless. the larger tips allow the paint to be thicker and flow much better.and allow you to spray a larger amount at a lower pressure.

so that would be my #1 suggestion for spraying larger objects like rockets.use the largest needle for your type of brush.I am almost sure it will make a big difference.

my second suggestion is using quality airbrush paints, the pigments are ground very fine and spray very nice thru an airbrush and usually require no thinning.plus the variety and depth of color is amazing.

using housepaints or lesser quality craft paints will work, but take a little trial and error to get right..the pigments are much coarser and can give a beginning painter alot of trouble.I highly recomend airbrush paints(like createx) to start out with, once you can get good results with that (and you will) than experiment with other mediums.before long you will get the hang of it and can spray just about anything thru it.

Rocketmaniac

Well-Known Member
Originally posted by moocrew
1 more question though.
Are you mixing the thinner and paint IN the jar you use to paint with...( the can you attach to the brush)?-
Matt,

No, actually I am mixing the thinner and paint in a plastic cup and then pouring the paint into the jar that attaches to the A/B

Rocketmaniac

Well-Known Member
Originally posted by stymye
I think the problem most people have is the tip size
for doing general spraying,see if you can get a large needle/tip. Most airbrushes come ready to spray plastic models and t-shirts, but will not spray a larger pattern very well,no matter how much you tweak the paint and air pressure.
Andy,

I did a little research on the internet for Badger replacement parts. Do I need a large needle and tip? What about the head and Spray Regulator?

Here's a website I found with the actual part breakdown diagram.

https://www.reuels.com/reuels/page292.html

Which of the parts do I need?

Stymye

Well-Known Member
ok...I went back and read the whole thread and looked at the pictures .what you have is a spray gun , not an airbrush.
That would be great for spraying medium viscosity materials such as glazes or even urethanes...I have not used one, myself so I can't say what I suggested so far will work with the sprayer like you have .

Rocketmaniac

Well-Known Member
Originally posted by stymye
ok...I went back and read the whole thread and looked at the pictures .what you have is a spray gun , not an airbrush.
Are you talking about the first pictures? I got rid of that thing a while ago. I just got a Badger 200NH airbrush.

Here's what it looks like

Stymye

Well-Known Member
ok ,, much better !

you will need the large needle (Bad50-0171)