Print

Print


The ground might also be a factor. 
K

On Sep 12, 2014, at 10:47 AM, Bruce Bartrug <[log in to unmask]> wrote:

This is just a guess (a SWAG based on the chemistry of acrylics) but that would happen with all brands all colors. Only, however, when the binding acrylic resin (medium) is diluted to a point where it won't bind the pigment.  Most acrylic media recommend not diluting them more than 10% with water.  That's a minimal amount, and I feel the rubbing off of color would occur somewhere past that point.  However, there are glazing and airbrush media that overcome the dilution of the binder resin, and these are readily available.

Egg tempera is one of the most durable and archival materials to use.

b

On Fri, Sep 12, 2014 at 11:28 AM, Karen Ackoff <[log in to unmask]> wrote:
It would be interesting to experiment a bit more with acrylics - diff brands, diff dilutions. 

I work with egg tempera, and as long as it is tempered properly, it can be diluted as much as you want (though egg tempera does not lend itself to washes due to its fatty nature). To temper it, I first make a pigment and water paste about the consistency of toothpaste. Then I take a small amount on my palette and approx the same volume of egg yolk medium (approx 2/3 egg yolk and 1/3 water), and mix with a palette knife. Then you can dilute it as much as you want. Some pigments require more/less binder, so this is approximate. Once mixed with egg medium it must be used while wet. While you can reconstitute it after it has just dried, the molecular structure is altered and the binder loses strength.

Probably more than you wanted to know. 

While I have used acrylics, I don't use them often, but have not had them rub off. I wonder if it happens with all brands, all colors. 

K

On Sep 12, 2014, at 10:16 AM, Lynette Cook <[log in to unmask]> wrote:

There's also a Golden "Airbrush Medium", though it is different from the Airbrush Transparent Extender and it clearly states on the label NOT to use the Airbrush Medium with varnish.

I notice that the transparent extender darkens the area in which it is used just slightly (where water will not). This is most obvious in areas where the extender is used "as is" without much paint pigment in it. A slight annoyance, but I can work with it.

Lynette

On Sep 12, 2014, at 8:02 AM, Bruce Bartrug wrote:

The Golden Airbrush extender is a good product.  I also have used it to thin acrylics.  It's an acrylic medium and one doesn't need to add water to dilute the color.  That may not give the same flow characteristics as diluting with water, but it's close.

b

On Fri, Sep 12, 2014 at 10:56 AM, Lynette Cook <[log in to unmask]> wrote:

I second Bruce's comment. I've been using acrylics since the 80s and never had a problem. And have no problems with the paintings I still have that are 30 years old - even on those where I used quite a bit of water to thin the paint down. In the "old days" I often didn't bother with varnishing, either. None of my painting teachers mentioned it in college. So I was floored about a year ago when I learned that thinning the acrylic down with water too much could lead to the paint flaking off even years down the road.


________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv


________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv




--
Bruce Bartrug
Nobleboro, Maine, USA
[log in to unmask]
www.brucebartrug.com

The world is a dangerous place, not because of those who do evil, but because of those who look on and do nothing.  - Albert Einstein

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv