TECH TIP: Mask for better silver stain application

Stains are corrosive to metals. I use brushes with plastic ferrels, a plastic palette knife, mix stains in plastic or glass containers and use a dedicated badger blender for stains.

Mask the area to be stained with contact paper.

Apply the stain broadly with a brush - keep the entire area evenly damp. The mixture should not be too wet. Consider this as a guideline: If you applied it to a horizontal surface the mixture would not drip.

Blend it with a badger blender.

Stop blending before the stain starts to dry. Dry the stain at this point with a hair dryer but be careful not to disturb it with too much "wind". When dry, remove the mask and watch for any stray flakes of dry stain that cling to the glass by static electricity. Remove these with a soft brush. Fire the stain face up in the kiln. It will contaminate the kiln shelf if fired face down. If you must fire the stain down use a removable barrier layer - like disposable fiber paper or a dusting of whiting.

You can blend the wet stain in a complex shape by masking as described above.

Here is another example of shading the application of stain. 

Question about Float Glass & Texture

Q: I will be contacting you in the next couple of weeks about scheduling the private class with you. In the meantime, I have another question. Is it OK to paint on regular float glass assuming that I will use enamels later on it or is that a no-no? If so, what do you do if you do not want any texture on the glass you are painting on. Artique works great, but the kind I have has A LOT of texture and I would rather use something flat. What do you think?

A: Float glass has a tin coating on one side that will affect silver stain and some enamel colors. You should always test float glass with a short wave ultraviolet light (sometimes marketed as a Tinscope or Tin-light). Mark the appropriate side of the glass for your use. Silver stain takes more intensely on the tin side of float glass. Enamels are another story. Sometimes interaction with the tin side is bad. I have had problems with some blue, green & turquoise enamels going grey or black. Other enamels, especially gold based colors – like pink, magenta, red & violet actually are more intense and saturated on the tin side - go figure! The answer, if you haven’t guessed it, is to test each color first.

Here is the link to the page on this blog that references UV light & Float Glass: http://thepaintedwindow.blogspot.com/search/label/UV%20light

As far as texture goes, that’s a subjective call. Personally, I paint on mouth-blown Lambert's or Desag (which is similar to Artique). I prefer the texture of these glasses. If I’m painting a face I would avoid a mouth blown glass with a lot of seeds and choose something smoother but surface striations are OK by me – that’s what we’re paying the extra money for after all! If you really find the Artique texture objectionable you can always flip it over – the back side is considerably smoother.

Happy painting!

BOOK RELEASE: Silver Stain - An Artist's Guide

I'm releasing my book: Silver Stain - An Artist's Guide.  In addition to all of the information in my silver stain tests included here on my blog there are dozens of additional illustrations and Technical Tips on glass painting.

You can view a 15 page preview of the 80 page book with this widget:

Silver Stain by J. Kenneth Leap | Make Your Own Book

Working on a book

The blog is great but some of you still like turning pages so I've started making a book on silver stain using "Book Smart" by Blurb!. The working title is:

Silver Stain An Artist's Guide

cover shot

screen capture

Applying Silver Stain by Hand

Silver stain applied with a brush

Wear a dust mask while handling the dry pigment. Use brushes with plastic ferrules, when possible, and mix stains in glass or plastic containers as silver stain is corrosive to metal. Clean your brush immediately after use. A dedicated set of silver stain brushes is recommended as silver stain can contaminate your other pigments. Silver stain can be mixed with any glass painting medium. Oil vs. water techniques will have an effect on the density and texture of the application but will not effect the color of the stain. The color results from the reaction of the chemistry of the stain and the chemistry of the glass. For the samples in this study I mixed the stains with distilled water and applied them with an airbrush. To achieve a gradation of color by hand: wet surface, apply stain, and blend with a badger blender. This guideline holds for both water or oil mixtures. It is better to achieve a gradation by diluting and blending while wet than by stippling the dry application. Most stains have their own binder so it is not necessary to add gum Arabic although adding gum may improve the flow of water mixtures. In some stains the binder is very stiff so you may find it easier to clean up stain while it is slightly damp or take my approach and mask areas to be stained with contact paper. 

The Temperature Tests

In the next round of testing I selected 3 stains and made samples fired at 100° F increments from 800° F to 1400°F. The kiln was held at the temperature indicated for 20 minutes. This test reveals how temperature effects the silver stain reaction. The sweet spot appears to take place between 1000° F & 1100°F. In the images below, the upper row of tiles are the tin side of float glass and the lower row are Lambert's glass. The first tile in each group was left unfired. At temperatures above 1300°F the clay body in the stain began to fuse to the glass which accounts for the dark tiles. None of the 1400°F tiles are transparent as the clay body could not be removed. The additional tiles in the 1000°F range are discussed in the next entry.

REUSCHE D292465 (Amber H465)

REUSCHE 1383 (Orange #2)

REUSCHE 1384 (Yellow#3)

Firing Silver Stain

The samples were fired in an electric kiln over a 2 hour period to 1100° F and held at that temperature for 5 minutes.

Samples are fired "face up"

BEFORE: Unfired samples

AFTER: Fired samples (before removing clay residue). Note the color change of both the clay and the glass compared to the unfired samples above.

Notes about Airbrushing Silver Stain

 APPLICATION NOTES:

At the time of application the following observations were made. Ease of straining and applying paint was noted. The amount of gum was judged by stippling with a white hog stippler.  If no comment appears about a particular attribute on the chart below it indicates that the performance was average for the group

Reusche (USA)
1382	Good stipple
1383	Sprays good, medium gum, stipples good
1384	Spray OK, stipple OK
1388	average
1390	Spray OK, stipple OK
D292465	Sprays good, heavy gum
Debitus (FRANCE)
10% S. Chloride	Gritty, hard to spray
20% S. Chloride	Gritty, hard to spray
40% S. Chloride	Sprays OK
20% S. Sulfide	average
40% S. Sulfide	Very soft, no gum
Amber	Very hard, lots of gum
Copper Red	Very soft, no gum
Oster (USA)
Ancient Winchester	Sprays good, stipples good
Ancient Walpole	Sprays good, hard to stipple, more gum than others
Ancient Lemon	Sprays OK, grittier than others, soft stipple, less gum than others
Keracolor (GERMANY)
76050	Mixes well, spray OK, firm stipple- about perfect amount of gum
↑1:4↓	Mixes well, sprays good, easy to stipple
73028/A	Very soft, little or no gum

Applying Silver Stain with an Airbrush

Use an eyedropper to transfer the paint.

Add paint to the airbrush. I use a Paasche H-5.

Apply the paint in a gradation to the test samples.

Number the samples. This stain is Reusche 1382.

Remove the samples from the easel.

Mixing Silver Stain for Airbrush Application

For my samples, I mixed 2 teaspoons of silver stain with distilled water.

Stir with a brush in a plastic cup.

Strain the mixture. I use 220 mesh silk screen cloth.

Most of the stain will be too thick to pass through the mesh.

Add additional water and stir, forcing it through the mesh with the brush.

The mixture should be the consistency of heavy cream.

Preparing the Glass Samples

Clean with glass cleaner

Attach double face tape

Mount samples on the Glass Easel

Moisten with alcohol

Clean samples again