Category Archives: Fusing

Fusing products, technical information and tips from Stained Glass Express.

Types of Glass

Other than basic opalescent and cathedral glass, there are further breakdowns of glass types under these two main headings. Opalescent is mixed with white and cathedral is see-through. Every manufacturer has its own variation of how it has handled these variations, so we end up with an industry filled with amazing options.

OPALESCENT

Opalescent glass was first developed and patented by John La Farge in 1879, but it was Tiffany who created the masterworks in glass using this type of glass. The Tiffany studio would often create a piece of glass just for the particular piece they were currently working on.

So within this category, there are the following variants:

Mixes. You can have a mix of one color and white. You can have a two- or three-color mix, or even a mix with more colors. The more colors that are mixed, however, the more difficult it is to not end up with a muddy glass. Mixing many colors with success is certainly a skill.

Iridized. Many manufacturers were adding an iridized coating to their glass. This is very thin metallic coating that gives the glass a mother-of-pearl effect (or for those who don’t care for it, an oil-slick effect).

Textured. There are many textures that can also be added to glass, such as flemish, granite, hammered, ripple, starburst, vertigo, corella classic and moss. Again, different manufacturers produce slightly different looks and may call them something different.

Solid Opals. Glass that is a solid color.

CATHEDRAL

This glass has been around a long time. References as early as 675 A.D. talk about colored glass in buildings.

Textured: There are many different textures of glass available. Some examples would be waterglass, reeded, English muffle, artique and Celtic.

Streakys. This style of glass is still a bit see-through. Some color is mixed with clear.

Circles from Squares

Courtesy of Bullseye Glass

These beautiful cabochons were made from square pieces of glass.

You can create nicely rounded cabochons from stacks of 0.75(20 x 20 mm) squares, thanks to heat, gravity, and the 6 Millimeter Rule. But be careful…they’re addictive!

Some Design Layer Possibilities

  • Blue/Vanilla part sheet: Scatter Steel Blue Opalescent coarse frit (000146-0003) onto a base of 3-mm Clear sheet glass, then sift a heavy layer of French Vanilla powder (000137-0008) over the top to cover. Fire to a full fuse. Maximize depth by arranging the Clear side toward the top of the stack.

 

  • River Rock Reaction (See Quick Tip: River Rock Reaction)

 

  • Pieces of Citronelle Opalescent (000221-0030) and

 

  • Turquoise Blue Opalescent (000116-0030).

 

The Stack

Top (6 mm): A “lensing” layer of Clear. This layer will stretch considerably. 

Middle (3-4 mm): This “design” layer will stretch and be visible through the top layer. Use part sheets or pieces of 3-mm sheet glass.

Bottom (6 mm): Typically not visible from the front. This layer will stretch the least. 

Tips

  • 6-mm Tekta Clear is a natural for this project. It’s more efficient, with fewer pieces to cut, clean and assemble!

 

  • Measure and score a grid of 0.75″ squares, then run them using the Rule of Halves. Two layers of 3 mm will also work.

 

  • A dab of GlasTac Gel will keep the stack together before firing.

 

  • The stacks flow out to about 1.25″ (32 mm) in diameter, so give them room.

 

  • For the cleanest release, we recommend firing on ThinFire.

 

Cabochon Firing Schedule

 

Rate Temperature Hold

 

1 400°F (222°C) 1225°F (662°C) :30

2 600°F (333°C) 1525°F (829°C) :30

3 AFAP 900°F (482°C) 1:00

4 100°F (56°C) 700°F (371°C) :00

5 AFAP 70°F (21°C) :00

 

Note: This heatwork goes beyond what the glass is tested for. Some styles

may opalize and/or shift in compatibility. Test before making multiples.

Y96 Firing Schedule Guidelines

Please adjust hold times for the size of your project.

Remember, this is only a guide.

 Full Fuse

  • From room temp to 1,000F at 300 degrees per hour, hold 10 minutes
  • From 1,000F to 1,250F at 300 degrees per hour, hold 20 minutes
  • From 1,250F to 1,425F at 300 degrees per hour, hold 15 minutes
  • Crash from 1,425F to 950F, hold 60 minutes
  • From 950F to 800F at 200 degrees per hour, hold 10 minutes
  • From 800F to 150F at 300 degrees per hour
  • Natural cooling to room temperature

Tack Fuse

  • From room temp to 1,000F at 300 degrees per hour, hold 10 minutes
  • From 1,000F to 1,250F at 300 degrees per hour, hold 20 minutes
  • From 1,250F to 1,350F at 300 degrees per hour, hold 10 minutes
  • From 1,350F to 950F AFAP, hold for 60 mins
  • From 950F to 800F at 200 degrees per hour, hold 10 minutes
  • From 800F to 150F at 300 degrees per hour
  • Natural cooling to room temperature

Slump Fuse

  • From room temp to 1,000F at 300 degrees per hour, hold 30 minutes
  • From 1,000F to 1,225F at 200 degrees per hour, hold 10 minutes
  • From 1,225F to 950F fairly quickly, hold for 60 mins
  • From 950F to 800F at 200 degrees per hour, hold 30 minutes
  • From 800F to 150F at 300 degrees per hour
  • Natural cooling to room temperature

REQUIRES EYE CONTACT.

REMEMBER, THIS IS ONLY A GUIDE.

Wissmach Luminescent Glass

Luminescent glass is different than iridescent glass. It is low-fire—not high-fire like iridescent—and is intended for reverse fusing.

What is reverse fusing?

Reverse fusing means placing your piece facedown on the kiln shelf and building backwards, fire-coated side down.

If you are firing on a textured mold, place a piece of ThinFire between your boron-treated mold and the glass. If you fire your piece with the coated side up or cover it with another piece of glass, you will lose the coating.

If you are slumping and do not go over 1,200 degrees, you can place the luminescent side up and not lose the coating.

Luminescent glass is food-safe and has been tested by the U.S. Food and Drug Administration. However, please note that once the piece has been fired in your kiln, it is no longer a Wissmach product; it is your product. If you have been firing glass that could leave lead or cadmium traces in your kiln, that could get on the product, which would render it unsafe for serving food or beverages.

 

 

 

 

LEFT: Luminescent glass fired with ThinFire in between, with the coating facedown.

RIGHT:  Luminescent glass fired facedown, directly on the mold.

 

Firing Schedules: Courtesy of Petra Kaiser and Wissmach Glass

Standard Fusing Schedule – 2 Layers Thick

Segment 1: 600°F/hr up to 1,000°F, hold for 10 minutes

Segment 2: Full/9,999 up to 1,410°F, hold for 10 minutes

Segment 3: Full/9,999 down to 950°F, hold for 60 minutes

Segment 4: 100°F down to 700°F, hold for 1 minute

Tack Fuse, Polishing and/or Slumping into a Mold

Segment 1: 300°F/hr up to 1,000°F, hold for 10 minutes

Segment 2: Full/9,999 up to 1,300°F or 1,350°F
(depending on your desired results), hold for 10 minutes

Segment 3: Full/9,999 down to 950°F, hold for 60 minutes

Segment 4: 100°F down to 700°F, hold for 1 minute

Draping over a Mold and/or Polishing

Segment 1: 300°F/hr up to 1,000°F, hold for 10 minutes

Segment 2: Full/9,999 up to 1,200°F or 1,220°F (depending on your desired results),
hold for 10 minutes

Segment 3: Full/9,999 down to 950°F, hold for 60 minutes

Segment 4: 100°F down to 700°F, hold for 1 minute

NOTE: Not all kilns are alike. Your kiln size, controller type and individual project may require some alteration to the schedule for best results.

Bottle Club

FUSING GLASS BOTTLES OR “HIDING THE EVIDENCE”

Don’t you just hate to throw out those wine and liquor bottles?  They are quite nice with the graceful shapes and the beautiful colors.   Make them into fused art!

First (and most important) step is to clean them.  The labels and any glue must be completely removed to be sure that no residue is fused onto the glass.  Use very hot water with ½ cup baking soda and 1 tablespoon of dish soap.  Submerge them in the water and let them soak for 10 minutes then add 2 cups of white wine vinegar.  Roll your bottles around so the vinegar mixes in.  Let them soak until you can get the labels off.

Once the bottles are clean you have some options.  You can just lay it in the kiln and full fuse it.  This one just has a little decorative wiring and some etching.  You could add a decorative knife and have a nice little gift.

Another option is to use a bottle mold.  There are all types available.  See the full collection here.

There are textured molds.  The one above has a lovely Tree of Life motif.

Drop molds, such as the one above, make an interesting shape.

You also can use a textured flat mold, such as the one below, and then slump it into a bottle mold.

You may get devitrification with some bottles.  To prevent it, spay with a divit spray like Spray A.

 

 

Tiffany Aventurine – A Celebration!

How beautiful is this VASE!?  (I FEEL LIKE I COULD JUST POST THE PICTURE AND IT WOULD BE ENOUGH!)

This vase was made c. 1910.  It is Aventurine Lava Blown Glass by Tiffany Studios.  This is currently on display in the new exhibition at the Morse Museum called “Iridescence—A Celebration”.

This vase was among Tiffany’s treasured A-Coll (Artist Collection) pieces exhibited at Laurelton Hall.  It is a striking vase and was made by draping lava like aventurine glass over iridescent gold glass.  The name aventurine references the quartz-like glass with sparkling particles developed in Murano, Italy around 1910 when this was made.

You can use aventurine glass for your treasures also.  Available from Bullseye and Oceanside in flat glass and frit.   Usually available in black, blue or green.  It has been a little tough to get lately but we have some.  Click here to order.

 

 

Glass Fusing Q&A

 

Q: When I fuse my projects, sometimes I get medium to small bubbles. What causes them and how can I prevent them?

A: Bubbles can be caused by many different things. First, uneven stacking of glass can result in air trapped between layers. To prevent this from occurring, check the placement of all the glass pieces and insure they are sitting properly on the base. Since the edges of the glass fuse before the center of the glass, cut your base glass 1/8” larger than the top layer to allow air to escape. Second, check the glass prior to fusing. Some glass may already have contained bubbles inside the glass, which may or may not affect the outcome.

Q: After I fuse my pendants, I get uneven areas around the edges. What’s happening with the glass?

A: You did not fire it long enough or to a high enough temperature for a full fuse. Try firing for a little longer time.

Q: Sometimes my glass pieces look like a porcupine with spiky edges. What causes the glass to spike?

A: Spiky edges can be caused by over-firing your piece. The spiked edges are caused by the glass grabbing as it is trying to shrink.

Q: What caused my layered glass pieces to flatten?

A: If the glass piece has flattened out too much, you have over fired the piece. To prevent this from happening, reduce your power and shorten your time. After your first firing, open the microwave and using Fireworks Hot Mitts™; carefully lift the lid to inspect the fuse piece. If the desired results have not been achieved, continue firing in 30 seconds intervals.

Q: I tried to make a 1 inch pendant with embellishments, however after I finished fusing, the glass shrunk. How can I prevent this from happening the next time?

A: Glass naturally wants to be ¼ inch thick when heated. Your glass will shrink or expand to obtain this depth. A good tip to remember is that if your piece is less than ¼ inch when you start, it will shrink up to reach this depth. If your piece is larger than ¼ inch when you start, it will want to flatten out to reach this depth.

Q: What causes two pieces of dichroic or iridized glass to blow apart in the kiln?

A: Repelling glass will occur with dichroic and iridized coatings. The coatings can’t be placed together for fusing purposes, because they repel each other. The only way to avoid this is to encase the coated glass with a non-coated glass, such as clear. This will cause the coated glass to be encased and sealed.

Q:  Yuck, this film appeared on my fused glass. What is it and how can I prevent this from happening?

A: This dull white crystalline substance on the surface of your glass is known as devitrification. This is one of the most talked about glass fusing problems around. It can occur when your glass remains in a temperature range 1000ºF-1300ºF too long. You need to minimize the time spent in this temperature range.

Gray or Scummy Edges – Gray or scummy edges can occur on pieces that have been fired once and then cold worked before refiring. Cold working involves using either a grinder or glass saw on a piece of glass. These can be avoided by thoroughly cleaning the glass before refiring the piece. Keep a bowl of clean water near your work area and soak the glass right after doing the cold work procedure. This will keep the edges damp and allow the piece to be cleaned easier. Scrub completely and let dry before proceeding with the refiring process.

Q:  My glass cracked! What happened?

A: Cracking glass either during or after firing can be caused by a several things: thermal shock, heating up the glass too fast and compatibility.

Thermal shock occurs either by taking the piece out of the kiln too soon, or by opening the kiln and exposing the hot glass to cool air.

If the glass cracked in the kiln and it has an “S” shaped crack, the piece has heated too quickly. Slow down!

Finally, if the crack occurs along the line where the two pieces of glass meet, then the two touching pieces are not compatible. Make sure the glass you are using have the same COE (coefficient of expansion).

Q: How can I prevent my glass from shattering?

A: Glass Shattering in pieces over 1” with more than 1 layer may sometimes shatter. To prevent this from occurring, reduce the power. This will allow the glass to heat slower and will be less likely to shatter. Next, make sure your glass is clean and dry before firing.

Q: My fusing instructions say to clean my glass before firing, can I use a glass cleaning spray or detergent?

A: We don’t recommend it. Detergents, dish soaps, multi-purpose cleaners, some window cleaners, ammonia and even denatured alcohol should NOT be used to clean glass. These can actually promote devitrification. We suggest diluted white vinegar or rinsing your glass with distilled water.

Q: Every time I put my fuse glass project together, the pieces roll off before I can get it to the microwave. What can I do to prevent this from happening?

A: To hold your fusing project together, mix one drop of glue.   Apply a very thin amount on the back of the glass using a brush and allow the glue to dry thoroughly before firing.

.. AND THE WINNERS ARE

Each year CBS (Coatings By Sandberg) sponsor a contest called “Dichroic by Design”

Here are this year’s winners!

First Place

Karen Pester “Noah’s Arc”

 

Second Place
Nathalie Strickland “Butterfly Fish” and “Hatching Turtles”

 

 

 

Third Place

Laura Dawson “Fish Totem”

There are also a few Honorable mentions, which are also wonderful.    If you want to see more, you can by following this link: CBS Contest and Winners

PAINT POURS—THE RAGE!

Paint pours are one of the most fun, exciting things to come along in our industry in a while.  It is easy, and the results are amazing.

Many people are doing this on canvas with acrylic paints, but in this industry we are going it on glass with enamel paints that can be fired.

To do one of these projects you need:  paints, layering mix, little cups, stir sticks, butane torch (optional), tray for catching the paint.

https://www.stainedglassexpress.com/glass-paint-layering-mix-8-oz-.html

https://www.stainedglassexpress.com/painting-markers/colors-for-earth-glass-enamels/

Some of the terminology you will hear are as follows:

Dirty Pour.  You pour/layer your paint in a cup and then set the glass on top of the cup and flip it over.  Let the colors slide down and then lift the cup.  So many variations.  You can slide the cup around before picking it up or tilt it.  After the cup is off you can blow with a straw or blow with the butane, drag something through it.  You can also just kind of sling/dump the paint from the cup.  Use more than one cup.

Straight pour:  Paint is poured/drizzled/dropped on the surface one at a time.   Then you can use the variations above.

Once the color is all over the surface you can wait a bit and then gently skin over the wet surface using an old credit card, palette, knife, fan brush etc.  You can use the butane to bring up bubbles or pop air bubbles.

Other fun things are to use a colander for pouring, or a sifter to sift dry powdered color on a wet base, a slotted spoon to create patterns, funnel to create pours.  Let your imagination run wild!

 

 

WHICH SIDE IS THE COATED SIDE OF DICHROIC

Some Info from The Frog Blog

Dichroic glass is so beautiful and there are so many uses, it is just delightful.  However, there are a few problems that knowledge can help deal with.

One is that it is impossible to tell 96 from 90 COE if you get them mixed up.  The answer to this one is—DON’T mix them up.  Keep them labeled.  If you keep scrap, keep it in a well-marked box.

It is often important to know which side the dichroic coated side is to get the look you are going for.  If it has a dark base, no problem—you can see it.  However, on a transparent base, it can look the same on both sides!  Reasons you may want to know this?

Cutting.  Always cut on the non-coated side of the glass.  It will help prevent chipping, especially on textured glass.  It also saves your cutter.

Coated Side Down.  When using the coated side down or capped with clear glass, the dichroic glass will have a smooth glossy surface and sparkle like glitter.  It will also change colors between the transmitted color and a completely different reflective color, depending of the angle of view.

Coated Side Up.   If you use the dichroic glass with the coated side up or uncapped, the dichroic surface will have a highly metallic sheen.  The piece may additional be rough and textured depending on the type of dichroic glass you are using.

This is what to do.  Place the glass over a dark background.  Look at the glass at an angle so that you are seeing the reflection of the dichroic.  Touch the surface with a paperclip (don’t scratch it).  The paperclip will reflect.

To know your answer.  Does the reflection meet the paper clip, or there a gap between the clip and its reflection?