Tuesday, 27 April 2010
Tuesday, 20 April 2010
Tuesday, 13 April 2010
pretty good. I've also put vinegar onto canvas by accident (thought it
was water) but it created a neat faux-finish look. Would you recommend
vinegar & sugar? Or is that a bad idea... I don't want to attract any
ants - haha!
Here were a few of my thoughts about adding sugar, salt and vinegar to her acrylics...
The question you sent is very interesting. Sand is a rather benign mineral that once glued down by the acrylic binder will be stable unless there is not enough “glue” to hold the individual sand particles in place. Sugar is very hygroscopic by nature this means that it likes to pull and hold onto moisture from the air or wet acrylic paint. What an artist may find is that films with sugar added in could be permanently water sensitive, possibly even mold, and yes attracting ants is a possibility. Golden makes Clear Granular Gel that has an acrylic solid in it that has some resemblance to very large sugar crystals. This product may be too regular in shape for this artist or does not allow them not sprinkle it on. Another option could be looking into recycled glass products as they are available in many sizes and grades.
Using vinegar in art is untested and would have to be considered veryexperimental. If one were to try this there are a number of issues to be aware of. First acrylic paints are produced with an alkaline pH that allows the acrylic binder particles to remain stable in water. If an acid like vinegar was poured onto wet acrylic the pH would be altered and there most likely would be acrylic shock that occurs. This may granulate the paint and would definitely weaken the physical properties causing less resistance to water, and solvents in the future. We have not tested the effect of vinegar, also known as acetic acid, on the longevity of art materials and would suggest caution when this may be of concern. While acetic acid is volatile we do not know how long it would take for a quantity to leave an acrylic paint film. This means that the curing process may be slowed dramatically causing unforeseen issues of stickiness or intercoat adhesion when layering. Also, some pigments are very sensitive to acids, for example if vinegar is placed on a dried film of Ultramarine Blue it will turn areas of contact white permanently.
Flooding dried Light Molding Paste with acrylic paint and water stains could offer interesting effects without the use of an acid. Also dripping or misting Airbrush Colors, or Airbrush Medium into stains made of water and acrylic paints offers many effects of diffusion, repulsion. If there is another specific effect this artist is trying to achieve we would be happy to try to figure out a way for them to create it.
Wednesday, 7 April 2010
I Introduction: What is acrylic paint
Acrylics paint is made with synthetic resin (poymer) as the medium (liquid) to bind the pigment (colour), rather than natural oils such as linseed used in oil paints.
- dries quickly
- water soluble
- versatile - can be used to emulate oil, watercolors or encaustics
- milky when wet (slightly opaque) but dries clear as opposed to oil paint which keeps the same colour wet and dry. à dry colour is always different than wet colour.
- shrink considerably (approximately 25-40%) upon drying.
Student vs Artist Grade acrylics:
Student grade acrylics
- less expensive pigments (or mixtures of pigments) so the
range of colors is limited.
- In the cheapest brands, they've lots of filler (chalk and kaolin or China clay.) .
- As with so many things, you get what you pay for.
- Don't mix together as successfully (in terms of color produced, not consistency),
- results as vibrant as artist's quality paints.
Professional Grade Acrylics:
What we have at OPUS, categorized in terms of consistency/thickness.
1. heavy body
heavy body acrylics:
smooth, rich, buttery consistency.
ability to "stand up" and retain brush strokes or palette knife marks
excellent flexibility when dry, greatly diminishing the possibility of cracking
- Liquitex (heavy)
- Stevenson (heavy)
- TriArt (heavy)
- Golden (heavy body)
- Open acrylics: Ideal for portraiture and landscape painting
Remain wet on the palette for prolonged periods without skinning over.
2. Medium body
(includes airbrush and ink)
consistency of pudding,
level out and don’t hold peaks.
Blend really nicely.
- Holbein acrylic gouache (medium body)
- Liquitex (medium/soft body)
3. Liquid /airbrush/acrylic inks
high pigment load or color strength
great for staining and washes
Great for fine line and details
illustrators loves them!
- Chromacolour (fluid)
- Golden fluids (fluids)
-Golden airbrush paints (very fluid)
- Liquitex and ---- acrylic inks (extremely fluid)
Gessos & Grounds
-light moulding paste
DEMO: liquid acrylics on absorbent ground and light moulding paste ground.
- Many pigments that are known to be toxic – cadmium & cobalt
- Acrylic paints contain additives such as thickeners, levelers, defoamers and surfactants to stabilize, prevent moulding and prevent them from drying too quickly. Your Skin my react to these.
- Acrylics de-gas when they dry. This gas can be toxic.
Reduce the chance of ingestion/absorption/inhalation by:
- Wear gloves or barrier cream
- Wash your hands thoroughly when you’ve finished painting.
- Don’t eat while you’re painting or have food in the studio
- Ensure there’s decent ventilation in your studio
- Keep your art materials out of the reach of kids.
II Mediums and Additives:
Gloss & Matte polymer medium
Colorless paint, as they are composed of 100% acrylic polymers similar to acrylic paint. A general purpose liquid medium useful for creating glazes, extending colors, enhancing gloss and translucency and increasing film integrity. Has a unique feel that is much more oil-like or resinous in nature and that promotes flow and leveling.
Show what we have
DEMO – using OPUS matte medium to seal a paper substrate surface. Using OPUS matte medium to extend paint
DEMO – using fluid medium to create glazing layersMediums for pouring layers –
GOLDEN Acrylic Glazing Liquid - is liquid medium designed to have longer working time than typical acrylic mediums.
Liquitex Glazing Medium - designed to dry quickly for rapid layering
Liquitex Gloss Medium and Varnish – not a true varnish, can be mixed well and easily with liquid paints to create layers of translucent glazes. Will crack if poured too thick.
GAC 800 - Adding small amounts of GAC-800 to the Fluids can reduce the crazing that occurs (that works especially well with the Fluids )
GAC 800 Sample to show - this medium can be poured thickly and used to embed objects without cracking.
The GAC’s liquid mediums defined:
- GOLDEN GAC - Golden Artist Colors
- Specialty Acrylic Polymers are based on 100% acrylic polymer emulsions.
- useful as mediums or modifiers of acrylic paints.
- can be blended with acrylics to extend the paint to:
1. regulate transparency,
2. create glazes,
3. increase gloss,
4. reduce viscosity
5. improve adhesion
6. Improve film integrity.
-have only a minimum amount of thickeners, levelers, defoamers and surfactants to ensure good film formation.
- very fluid and thinner than other GOLDEN Mediums.
- will reduce the thickness of most GOLDEN Acrylic Paints.
Gels can be thought of as colorless paint, as they are composed of 100% acrylic polymers similar to acrylic paint. They can also act as adhesives in collage and mixed media that dry to form continuous films with excellent flexibility with chemical, water and UV resistance.
Soft -> Regular -> Extra Heavy
Soft Gel Gloss –
moderately pourable. Hold only slight peaks. The recommended acrylic to function as a glue for collaging. Soft Gel Gloss is ideal for glazing and other techniques where transparency is desired. Useful as a non-removable isolation coat, applied over the painting and before the varnish (must be thinned with water - 2 parts Soft Gel Gloss to 1 part water). Adding water and thining it prevents clouding.
DEMO – using Golden soft gel as an isolation coat.
Regular Gel - Same creamy consistency as GOLDEN Heavy Body Acrylic colors. Ideal for extending paint and regulating translucency without changing the consistency of the Heavy Body and Matte colors. Hold moderate peaks and texture. The Regular Gel Gloss is ideal for glazing and other techniques where transparency is desired.
DEMO – using regular gel to create underpainting texture – on its own or mix with paints.
DEMO – putting regular gel on top of your painting to add depth and texture and thick glazes on your paintings
Heavy & extra heavy gel - Thicker consistency than GOLDEN Heavy Body Acrylic colors. Blend with colors to increase body. Good for holding peaks. * note that it dries translucent – not perfectly clear.
Clear tar gel - mixes with the Fluids for dripping purposes, and can yield lines that range from spider-web fine to brushstroke thick.
Sample Handout - using ALL various gels as glue to adhere and embed stuff into your painting
Self leveling clear tar gel - isolation coat that dries evenly
(GOLDEN medium that work especially well with the Fluids)
Impasto Gel Medium - (steveston) like regular gel but has marble dust so its opaque.
Modeling Paste - regular, light and coarse. Can be used as a ground and to build up texture into your painting.
Acrylic Flow Release - is a surfactant. A surfactant is a concentrated surface-active liquid which reduces surface tension, thus improving wetting and increasing the flow of acrylic waterborne paints.
Retarder – slows the drying time of paint. Allows greater time for blending, working outside.
IV Painting Substrates and Accessories
glass, board, canvas, linen, paper.... (display)
BRUSH HEAD BASICS:
1. round – use to dab & make a line
2. flat head – landscape, horizons, washes/glazes
3. bright – less flexible than a flat, more control
4. Filbert – oval dabbing and filling in shapes, most versatile
What we carry:
Fortissimo – ($)
- natural hog hair
- oil brush works great for acrylic
-stiff and thick hair – good for dry brushing and brush stroke effects
- really soft
- great for the fluids/inks
- won’t work so well with the heavy body paints
- More firm
- even firmer
Windsor and Newton water mixable brushes ($$$)
- have a fan brush, great for blending
Robert Simmons ($$$)
- hold a lot of water/paint
- very soft
- lots of selection of small sized brushes for detail
Other - palette knifes, rubber shapers are cool to use too!
Peel- away palette
Clear plastic Palette
Cansen disposable palette
Stay Web Palette
Wipe acrylics off with a papertowel so you don't get it down the sink
Master's paint cleaner and brush conditioner
Glass jar with coil