Iwata external MAC valve

I'm wondering too. I've always wondered what the MAC valve does that my regulator won't do.

Mike, you out there?

I have 2 Iwata brushes and I have no idea, other than giving you another place to control the pressure, what this valve would do for me. I guess, if in your setup, your regulator is out of reach, it would be great. But for me, it seems overkill.

Rich

hkshooter wrote:

I'm wondering too. I've always wondered what the MAC valve does that my regulator won't do. Mike, you out there?

Moi? I have never used one and it seems to me like a gimmick although I have heard some people say it works great. My point is, and always is, why do we need this type of airbrush for modeling? These kind of things of airbrushes that are designed to push the envelope so to speak on getting the finest lines possible are geared to automotive and fine art airbrushing with very thin paints and very small pigments. Most model paints just don't fit that criteria and even if they do what are you trying to accomplish? Do you want to build a 1/32 scale P-38J and freehand Richard Bong's wife "Marge" on the nose?

My regulator is right next to me, no need for another one. Good point you made about the brush capabilities too, Mike. I just can't see my needs or abilities needing any more air brush than those which I have.

Many thanks for the comments. I guess the jury is still out regarding the MAC valve.  It appears that it is really not necessary.

 Morto

morto wrote:

Many thanks for the comments. I guess the jury is still out regarding the MAC valve.  It appears that it is really not necessary.  Morto

The Iwata web site provide a very good guide on usage of airbrushes:

http://www.iwatamedea.com/uses/guide.jsp

The MAC valve is aimed at the illustration artist. Mike is right that modeler seldomly need that kind of a MAC control. And the value of an external MAC device is not established.

F105-Thud wrote:

With the MAC valve fully in, no air comes out of the airbrush. Open it up gradually, and it`s just like using a regulator, you can adjust the amount of air to your hearts content, depending on how much your compressor is pumping out of course.

This valve does not regulate air pressure, but regulates the amount of (CFM) of air supply. In otherwords it's what's known as a needle valve. The air pressure will build up ahead of the valve, but not downstream from the valve. A regulator works the opposite way, and does not control the amount of air volume going thru it.

gary

Thanks again for all of the comments.  I'm still considering the external MAC valve as I think it will help with low CFM needs.

Morto

squeakie wrote:

F105-Thud wrote: With the MAC valve fully in, no air comes out of the airbrush. Open it up gradually, and it`s just like using a regulator, you can adjust the amount of air to your hearts content, depending on how much your compressor is pumping out of course. This valve does not regulate air pressure, but regulates the amount of (CFM) of air supply. In otherwords it's what's known as a needle valve. The air pressure will build up ahead of the valve, but not downstream from the valve. A regulator works the opposite way, and does not control the amount of air volume going thru it. gary

For all practical purposes they are the same thing. 

The CFM of an airbrush is so low it's almost not even worth considering. 

Here is an excerpt from airbrushtalk.com: 

11. How much air is necessary to operate an airbrush?

As a rule of thumb, you need « cubic foot of air (cfm) at 30 pounds per square inch (psi) to propel an airbrush. You can work at lower or higher pressures, depending on the materials sprayed and the effects desired, but the cfm requirement remains the same.