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Hi all:

Sorry for this question if it's been covered previously... I tried searching w/o success...

I've not ever modelled with an airbrush/compressor before and I'm shopping around for an economical combination that will be successful for me.

One question that has come up is the PSI range. What is the ideal range for spraying models? 10-25? Lower, higher?

Thanks. md

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That question is not easily answered, as you will need to vary your pressure depending on how your paint is mixed and what affect or finish your trying to shoot.

But you will need at least 25-40lbs pressure from any type of air-source, you will regulate the pressure with a regulator.

And you should always set your pressure with the trigger down (air flowing) as the static pressure with the valve closed will be higher.

I have to say I seldom look at my air pressure gauge as I set my pressure to (as mentioned before) my spray pattern coming out of the brush, But I usually start at 20psi then adjust up or down form there as needed.

Curt

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20 psi or less works for me.

25 psi would be an absolute upper limit for me.

Sometimes less than 10 psi if I'm working close in and want good control over things.

Think of it as lightly brushing paint on with air as the brush.

Bob

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The air pressure you use depends on what type of airbrush you are using. Ones with the paint cup underneath will need more pressure to suck the paint up, normally about 20 to 25 pounds. However, a gravity feed airbrush has the paint cup on top of the airbrush and requires much less pressure, about 10 or 12 pounds.

Also, the amount of pressure depends on how thin the paint mixture is that you are spaying, with the thinner the mix the lighter the air pressure.

But the big factor is the type of feed you are using. So just talking about air pressure without specifying the type of feed is not very meaningful.

Warwick

Edited by wdw
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Ah... light bulbs are coming on...

I'm looking at a gravity fed, double action brush. Paints will be acrylics and enamels, thinned as usual, most of the stuff i've been building is 1/72 jets, so some small detail is needed, but some broad use too.

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I'm looking at a gravity fed, double action brush. Paints will be acrylics and enamels, thinned as usual, most of the stuff i've been building is 1/72 jets, so some small detail is needed, but some broad use too.

If you will be using a double action gravity feed, you don't need a powerful compressor but you should get one with an air tank if your budget permits. It will extend the life of your compressor because it will only kick in when your tank falls below a certain PSI. You get more quiet time to work and less compressor running in the background. Oh, and try to stay away from those diaphram compressors and look for piston type instead. They're noisy!

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For some reason, no-one ever mentions airflow, which is just as important. If the compressor doesn't deliver a minimum of half a cubic foot of air per minute, it's unlikely to keep even an average airbrush supplied.

Edgar

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That question is not easily answered, as you will need to vary your pressure depending on how your paint is mixed and what affect or finish your trying to shoot.

But you will need at least 25-40lbs pressure from any type of air-source, you will regulate the pressure with a regulator.

And you should always set your pressure with the trigger down (air flowing) as the static pressure with the valve closed will be higher.

I have to say I seldom look at my air pressure gauge as I set my pressure to (as mentioned before) my spray pattern coming out of the brush, But I usually start at 20psi then adjust up or down form there as needed.

Curt

For some reason, no-one ever mentions airflow, which is just as important. If the compressor doesn't deliver a minimum of half a cubic foot of air per minute, it's unlikely to keep even an average airbrush supplied.

Edgar

Both Netz and Edgar have good points. The compressor needs to have sufficient capacity with margin. 0.5 CFM AT 45 psi or higher flow and pressure is very important. You need some margin to maintain a steady flow.

This kind of CFM and PSI is small for tool/garage compressors which are too noisy for indoor use. Many small airbrush compressor cannot meet this requirement. This can be easily tested out. Connect you airbrush to the compressor the normal way. Set the regulator pressure to 50% higher than what you use, say, 30 psi. Push down on the airbrush trigger fully to get a strong air stream. The regulator pressure reading should not change more than 0.5 psi lower and remains steady no matter how much you push the trigger.

If the regulator pressure gauge reading changes too much, there are several possibilities:

1. Poor compressor quality that cannot maintain pressure. It is particularly true for older diaphram type airbrush compressors. But is also true for many cheap compressor sold on Ebay.

2. Low quality orifice type regulator. A higher quality regulator should say "true diaphram type". The orifice type is what you may probably get paying $20-30 for the regulator at a hardware store, such as Lowes or Home Depot.

3. The manufacturer installed the gauge incorrectly. It allows the flow dynamics to affect the reading.

I use a 17-21 psi setting for most of time using the Iwata Eclipse HP-CS. Down to 15-16 psi occasionally using very thin paints such as NMF. Sometimes, user reports low pressure setting due to incorrect readings. It must be taken into account.

My compressor? I use an older model Paasche DA400 when they were still made by Sparmax in Taiwan. The 1-gallon airtank and large face gauges are home-made add-ons. The regulator is at the workbench after the 25-feet coiled airline. The airtank is NOT necessary to keep constant pressure with the DA400 compressor which is strong enough to keep pressure well on its own.

3813927753_3bb9295b07.jpg

Edited by Kei Lau
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I've not ever modelled with an airbrush/compressor before and I'm shopping around for an economical combination that will be successful for me.

eBay is your friend there. :whistle: Then again, if you're in the US, I heard that Harbor Freight can sometimes beat eBay...

There are many different views in terms of what airbrush and compressor to get. You can spend hundreds of your hard-earned $$$ on airbrush and compressor that can last you a lifetime (hopefully...), or you can spend less than $100 for both if you don't really care about the longevity.

Personally, I'm more of the latter. Got my airbrush and compressor off eBay, very similar to THIS. Been 2 years since I got mine, and still going strong. :thumbsup:

HTH

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A max of 35 psi sustained capacity with as much CFM as possible. Airbrushes don't need 120 psi, but they do need volume. More psi capacity is acceptable as long as you have a good regulator to drop the pressure down to a normal working range of 10-25 psi again with sufficient CFM. Read your air brush spec sheet for requirements.

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Thanks for the replies guys... just to continue this... I do already have a compressor, but I'm afraid it might not be good enough. Let's see what you all think... maybe it will work w/ some mods...

It's a Craftsman Industrial, small pancake style (I think that's what it's called), 1.5 hp, 4 gal tank, 120 psi, delivers 4.7 scfm @ 40 psi, 3.3 scfm @ 90 psi.

The dealio is it does not have a moisture trap and the little dial that tells you how much air is there is small gauge that isn't precisely graduated under 20. I'm wondering, is it difficult to add a moisture trap and is it difficult to change the gauge? It'd be great if this could work w/ little work and $...

Thanks again.

Michael

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Thanks for the replies guys... just to continue this... I do already have a compressor, but I'm afraid it might not be good enough. Let's see what you all think... maybe it will work w/ some mods...

It's a Craftsman Industrial, small pancake style (I think that's what it's called), 1.5 hp, 4 gal tank, 120 psi, delivers 4.7 scfm @ 40 psi, 3.3 scfm @ 90 psi.

The dealio is it does not have a moisture trap and the little dial that tells you how much air is there is small gauge that isn't precisely graduated under 20. I'm wondering, is it difficult to add a moisture trap and is it difficult to change the gauge? It'd be great if this could work w/ little work and $...

Thanks again.

Michael

The tools/garage type compressor has too much of everything, pressure and airflow, oil and noise. You can get a regulator/moisture trap unit like this to reduce pressure and hope that oil will not get to the airbrush. But you also need a high tolerance of noise and a very understanding family to use it indoor.

ABDTFR2000_200w.jpg

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The tools/garage type compressor has too much of everything, pressure and airflow, oil and noise. You can get a regulator/moisture trap unit like this to reduce pressure and hope that oil will not get to the airbrush. But you also need a high tolerance of noise and a very understanding family to use it indoor.

ABDTFR2000_200w.jpg

Thanks for that link. I own a small farm with no one around for quite a ways, so neighbors aren't an issue. The wife and kids are fine as well as long as I'm in the garage, lol.

Since it's just 20 smackers, I think i'll give it a shot and see what comes of it.

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Has anyone used the Paasche D3000R compressor? I'm looking for a new compressor with an air tank.

The Paasche D3000R should work fine with most airbrushes.

Also take a look at the Paasche DA400R. I will pick a more powerful motor over a weaker motor with tank in choosing compressor for airbrush uses. The DA400R is only $20 more.

DA400R.jpg

If budget allows, also take a look at the Sparmax and Iwata compressors for better quality and long term durability.

Edited by Kei Lau
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The Paasche D3000R should work fine with most airbrushes.

Also take a look at the Paasche DA400R. I will pick a more powerful motor over a weaker motor with tank in choosing compressor for airbrush uses. The DA400R is only $20 more.

DA400R.jpg

If budget allows, also take a look at the Sparmax and Iwata compressors for better quality and long term durability.

Thanks for the advice. :)

Doesn't a tank reduce pulsing when spraying?

BTW, I use a Paasche VLS airbrush.

Edited by crowe-t
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Thanks for the advice. :)

Doesn't a tank reduce pulsing when spraying?

BTW, I use a Paasche VLS airbrush.

In theory, the tank helps. But you shall not sense the "pulsation" if you have have a good compressor. See my earlier post on this thread about adding a tank to the Paasche DA400.

In the old days, the single diaphram compressor are so weak in power, people complained about pulsation. Most of the modern piston driven compressors are powerful enough, including the better made, single piston ones, that a tank is not necessary to reduce pulsation. But the tank still helps to reduce the motor on-off and eventually prolongs the compressor life, again, in theory.

If your budget allows, consider the Sparmax TC-5000 or the Iwata Powerjet Pro. Both are twin piston with tank. If budget is an issue, I would choose a dual piston over a single piston with tank. The twin piston one runs cooler and slightly quieter.

Any of the compressor discussed should work fine with your VLS.

Edited by Kei Lau
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  • 2 weeks later...

In theory, the tank helps. But you shall not sense the "pulsation" if you have have a good compressor. See my earlier post on this thread about adding a tank to the Paasche DA400.

In the old days, the single diaphram compressor are so weak in power, people complained about pulsation. Most of the modern piston driven compressors are powerful enough, including the better made, single piston ones, that a tank is not necessary to reduce pulsation. But the tank still helps to reduce the motor on-off and eventually prolongs the compressor life, again, in theory.

If your budget allows, consider the Sparmax TC-5000 or the Iwata Powerjet Pro. Both are twin piston with tank. If budget is an issue, I would choose a dual piston over a single piston with tank. The twin piston one runs cooler and slightly quieter.

Any of the compressor discussed should work fine with your VLS.

The Iwata PowerJet Pro has a 2 liter air tank? Wouldn't a larger tank(3 liter) be better?

The Iwata compressors seem to be priced higher then others.

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As I gain more experience with the airbrush and different paints and/or mixing ratios, I find that I spray best with really thinned paints (50/50 paint/thinner for enamels, sometimes a bit more thinner too!) and low pressures, about 10PSI and even 5psi...works really great so far. Anything at 20psi comes out hitting too hard I find.

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As I gain more experience with the airbrush and different paints and/or mixing ratios, I find that I spray best with really thinned paints (50/50 paint/thinner for enamels, sometimes a bit more thinner too!) and low pressures, about 10PSI and even 5psi...works really great so far. Anything at 20psi comes out hitting too hard I find.

I don't think that 5-10 psi will work with most modeling paints. Make sure that the pressure gauge readings are the same before and after you push the airbrush trigger. If not, your gauge is not reading accurately.

If the paint hits too hard (whatever that mean), you are unlikely to be using only 20 psi. You may have a pressure gauge problem.

Edited by Kei Lau
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I don't think that 5-10 psi will work with most modeling paints. Make sure that the pressure gauge readings are the same before and after you push the airbrush trigger. If not, your gauge is not reading accurately.

If the paint hits too hard (whatever that mean), you are unlikely to be using only 20 psi. You may have a pressure gauge problem.

I installed a new regulator on the compressor, but I suppose it's possible that it does not read correctly, however, on my guage, those are the pressures I go by. As for the pressure gauge readings both before and after I press the trigger, they will most certainly have to be different because pressing the trigger will release pressure, decreasing the reading. I think that was stated earlier in this thread too.

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I installed a new regulator on the compressor, but I suppose it's possible that it does not read correctly, however, on my guage, those are the pressures I go by. As for the pressure gauge readings both before and after I press the trigger, they will most certainly have to be different because pressing the trigger will release pressure, decreasing the reading. I think that was stated earlier in this thread too.

The pressure gauge should measure the static pressure at the compressor outlet. If set up correctly, the reading should not change. With a good setup, the compressor pressure should not have changed according to the amount of air or thickness of the paint you use.

If the reading changes when you press the trigger, it is either the compressor is too low powered to maintain pressure, or the gauge not set up correctly to measure the static pressure. Yes, my first compressor, a Silentaire Scorpion-1, did that. The motor does not have enough power. I set the pressure at 25 psi with a Paasche H. The reading drop to less than 10 psi when I airbrush. My Paasche DA400 will not do that. Please, see my earlier post.

So what are the 5-10 psi you quoted? Before or after you press the trigger. If after, how many psi it drops when you do?

Believe me, if you set your compressor at 5 psi, it may not work very well when you press the trigger. Well, it may not work at all.

Edited by Kei Lau
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