Full fuse firing schedule for window or bottle glass

Ramp                                                   Hold Temp                               Hold Time

300/hr                                                   500                                            15 min

250                                                       1100                                          10 min

250                                                       1550                                           8 min

9999                                                     1030                                          20 min

50                                                          940                                            no hold

100                                                        740                                           off 

Kokomo Glass kiln firing schedule

Some General Information about Fusing with Kokomo Glass

Annealing Temperature for Cathedral Colors:

Anneal: 945 F
Strain Point: 872 F

COE: Generally in the neighborhood of 92-94, but you will need to test each sheet if they are from different runs. Even different runs of the same color can have significantly different fusing properties.

Annealing Temperatures for Opals:

Opal D Anneal: 891 F Strain Pt. 833 F
Opal M Anneal: 914 F Strain Pt. 851 F
Opal ML Anneal: 930 F Strain Pt. 862 F
Opal L Anneal: 936 F Strain Pt. 867 F

Typical Ramping Up?Allow 1 hour per ¼? of thickness. All kilns behave differently. Test in your kiln to adjust for faster or slower times. Projects with more surface area may require slower ramping.

Typical glasses will begin to sag at around 1050 F.
Annealing:Soak 1 hour per ¼? of thickness @ 945F
Ramp to strain point 872 F

(1/4" thick piece should take 2-3 hours)

Soak @ strain point 15 minutes per ¼? thickness
Ramp down to room temperature.
For ¼" thick piece, turn kiln off and do not vent until 250 F.

If you are fusing Kokomo glass, Experiment, Experiment, Experiment and Test, Test, Test. Some colors devitrify more than others. Reds and yellows hate to be fused.
Finally as to whether the ring mottles can be used in fusing: 
As far as slumping our glass, Kokomo has experimented with slumping our glass & have found that on the opals it is critical to catch the glass right when it falls then vent the kiln down to 1050F as quickly as possible, then follow your normal ramp down.

Youghiogheny Glass full fuse firing schedule

From room temperature to 800F at 300 degrees per hour, hold for 10 minutes
From 800F to1120F degrees at 300 degrees per hour, hold for 10 minutes
From 1120F to1250F degrees at 200 degrees per hour, hold for 10 minutes
From 1250F to 1560F fairly quickly, hold for 10 minutes
Crash from1560F to1020F and hold for 45 minutes
From 1020F to 800F at 60 degrees per hour hold for 30 minutes
From 800F to 300F at 100 degrees per hour hold for 5 minutes

Uroboros and Spectrum System 96 glass full fuse firing schedule

Today I thought I'd share my favorite firing schedule for Uroboros glass (it works great for Spectrum 96 COE too).  This is for full fusing two layer pieces.

300° - 1150°  hold 30 minutes

200° - 1370° hold 20 minutes

400° - 1470° hold 5 minutes

9999° - 950° hold 60 minutes

150° - 800° hold 10 minutes

300° - 500° no hold

You will notice that when fusing transparent glass you will not need as much heat as firing opaque glass.  It is only a matter of a few degrees.  You can tell if you need to turn down the heat used on your highest full fuse temperature segment if you have small glass burrs sticking out on the sides of your finished piece.

It is advised to try this schedule with your kiln on a test piece first to make sure it is good for your kiln!  Kilns don't always heat up to the same temperatures as other kilns do.  If your finished fused product seems slightly indented or distorted on the side edges, you need to turn down the high temperature.  Mine is 1470° (hold 5 minutes).  You might want to program your kiln to heat up to 1450 instead and perhaps hold longer.  Again test your glass sample first before firing your good piece!

Painting kiln glass, notes

This information written by Deborah Read is really good for glass painting.  If you would like to read more from her, click here to view her webpage.

Painted Beads 101

Note: the following method is only one of many that can be used. This is how "I" am using the various paints to make "my" painted beads. Follow all product safety instructions !

Black Trace Lines

I prefer a black trace line on my beads - basically painting a black outline and filling in those lines with color or mattes to give the bead color or depth. This can be accomplished in many ways, but my preference at this time is using a Reusche Trace Black powder and mixing with Squeegee Oil. There are many types of binding mediums that can be used to mix this trace powder but I use the Squeegee Oil due to the fact that there is little smell while painting and during firing. You are using an oil to give you more time to use the paints and I find the oil gives you a really nice "flow" to the paint. I am also using Reusche brushes purchased directly from Reusche.

Materials list for Trace Lines:

Brush Method Squeegee Oil (Thompson Enamels A-4)

Reusche Trace Black E-401 (Delphi Glass, Reusche direct, many sources for this)

Reusche Tracing brushes (I got from Reusche)







Another option could be the Paradise paints in powder form that is now available

Pallet Knife (for mixing), Eye Dropper (for adding Squeegee Oil) Sheet of glass (for mixing on) Turpentine (for thinning mix for painting)





Its hard to say how much paint to use - depends on how much painting you expect to do - It is easier to make more than it is to have made too much and waste it.

I take about a teaspoon of E-401 and put into a pile on the mixing glass and add squeegee oil, using an eye dropper, till it is a thick paste.





I mix using a pallet knife. Once made you can either paint or use this thick paste on stamps - I tend not to thin the paste for rubber stamps.









If I am painting I take a little turps on my brush and pull some of the paste from the main pool of paint and thin out enough that it is still dark when applied to the glass. I use a roller to apply to the stamps but again whatever works for you.



Materials List Painting:

Pen/ink method

Using the same Reusche E-401 I mix with Clove oil to a consistency that gives a solid black line when used with and ink pen nib - I am using an inexpensive ink pen and nib for fine lines. Came as a set.

You just have to get used to how to mix your paints and how to use the pen - Took a couple of times not to get big blobs of paint on the glass - but at least it wipes off.





After a while its pretty easy

Samples of the ink drawing: Easy to get fine lines





Glass

When using Morretti rod - use Morretti sheet glass (I got from Frantz) so what ever you have in flat use in Rod - Compatibility issues

Clean your glass and either stamp or paint the trace line

The best part of painting on glass is that if you make a mistake you can wipe it off.

FIRING

Fire piece - painted side up



I fire the Reusche up to 1325F but you only need to fire between 1100 and 1425 for it to adhere - so to save time you can fire above 1100 and shut off kiln - and you can cool quickly -

I am using a HOAF infrared kiln that runs on Propane and it take about 6 mins for it to get to 1325 and about 10-15 min to cool enough to grab out of the kiln for the next step.

At this point I now have a permanent trace line on my glass that will not come off. I can either continue to apply mattes (part of traditional glass painting and you should really look into classes) or I will paint with colors.

PAINTING WITH COLORS





Currently I am using Paradise Paints as they can come premixed (with Pine Oil) The only drawback is the smell - you really do need good ventilated area to use and when you fire. (To purchase go here: http://www.paradise-co.com/paints/pricing.html ) They now have powder form to mix with whatever medium you want to use. I am gong to use the squeegee oil for less smell - testing will let you know how they work out.

Another option may be using the Paradise Paints powder form in the same way - Works great with squeegee oil and or pine oil- just mix well and thick

There are Fusemaster, They have a larger color pallet than Paradise. A lot of tranparents.

Thompson and other various enamels on the market you can use or try. I would use the squeegee oil with them also - I am currently purchasing the Paradise paints in powder form so that when I finish using up the premix I will mix my own with the squeegee oil and I will not have to deal with the smell. !

PAINTING

The Paradise Paints are thick and cannot be thinned with Turps (that your using with your Reusche) they suggest not thinning or it will give a thinner and less opaque color on your glass. (But if you do thin you use Pine Oil) and they require Mineral Spirits -paint thinner, lacquer thinner or acetone for clean up - do not use these to thin the paints or any other thinner you may have used with paints. I have been using directly from the jar - thick and applying. Since you have your trace line - its like a coloring book and you fill in. Paradise also advised that if you warm the paints they will thin out in consistency but not in color opacity.

(Reverse painting)









If you make a mistake you can wipe the color away and your black trace line will still be there !

I fire these paints at 1325F also - only to be consistent - you can fire these at a lower temp to get them to adhere - you need to vent up to 500F for binders to burn off and to keep your red - red (read paint info).

I have tried putting pieces into my bead kiln and then using - bead kiln is only up to 950 but it burns off binder - makes area stinky ! so I rather get rid of the smell all at once and this way I can make a lot of pieces and torch at a later date without worry that I may scratch the paint off.

So you may choose to do a day of painting when you know you have to get up and do other things and be able to walk away knowing you can come back and resume where you left off.

Works in progress - various stages - fired - unfired - painted unfired

APPLYING TO A BEAD

Now comes the tricky part (not the hard part) the tricky part. You can put pieces into your cold kiln but I found I could introduce them to the edge of the opening and push them in - being such flat thin pieces they have not broken or shattered on being introduced to a hot kiln (mine is 950 or so) NEW HOT PLATE TECHNIQUE. I bought an industrial hot plate that goes up to 1000 degrees F and this allows me open sides and top to be able to see my painted piece and line it up better

(they must be painted side up !)



Here are options for making bead - you can either eye it or before you put piece in the kiln/hot plate or mark your mandrel for the length of the piece your applying - I have been using a permanent black marker on my bead release on the mandrel - you do not need a big mark - just enough to show where ends are. I put the pieces in the kiln on an angle so when I place the bead to stick to it I get a better angle on how to attach.

The worst part is figuring out how much glass to apply to your base bead - before you wrap your flat piece on - can be tricky but remember - if your piece is too big once you apply (and hope you get most of your design on) you can use glass shears to cut off the piece (cool huh !). I have been outlining the piece on my marver and rolling my base to see if it fits within the parameters.



Once you have your base bead made (and I try to make that base a little smaller than what is necessary so I can tuck the ends of the flat glass piece in to make a neater bead) here comes the really tricky part.

I heat up my bead to glowing but not runny and you know that the glass is going to stick to anything glass you touch - open door to kiln and touch it down on your piece to grab - you need to line up where you want to start the attachment, as it is difficult to re-center once attached - you can heat up an move but you may distort your picture.



I try to center on pic so that I have main area of pic attached to bead and work from center out applying . I did try to use tweezers but trying to open the door grab - hold onto hot bead was really a tricky balancing act this way one hand on door one hand on bead and glass.

Quickly remove from kiln and into end of flame and heat up - start from center and heat up glass (keeping bead hot but try not to have direct flame on painted side as you can burn off paint as torch is much higher than the enamel firing range)



See the black lines in face - I did not apply enough paint and I burned off in flame

Now work side to side heat up glass (working from center) and using any tool that feels good (I use my Sharon Peters razor tool) to push slowly down and work the glass onto the base bead - working from center and making the most out of the pic till the edges almost meet - here you judge if you have to trim any glass - and get the edges together - heat and melt - heat and melt keeping them from overlapping and giving a lump.

Work your bead and keep it good and hot - you need to make the outside glass one with the inside glass - marver shape and do edges - I heat ends and work till done

Get it good and hot - wait till ready for kiln and put into kiln and anneal

and you too can have too many painted beads lying around !

System 96 Firing Schedules - reference guide

Find all of this valuable information and more about System 96 glass on their web page by clicking right here.

Firing Guide

FAHRENHEIT (need Celsius?)

Firing Schedule:		Guidelines for firing projects up to 3/8-inch thick.
Slumping Schedule:
THICK Firing Schedules:		Guidelines for firing THICK projects ranging from 1/2-inch to 2-inches thick
Forming Chart:		Forming stages, definitions, and temperatures for firing System 96 products.
Bubble Squeeze:		Adding a stage during firing to reduce or eliminate bubbles
4-Segment Firing:		How to easily adapt our 6-segment programs to 4-segment controllers

Firing Chart (For projects up to 3/8" thick)
Segment	Rate		Temp	Hold
	(°F per Hour)		°F	(minutes)
1. Heating I:	300		1150	30
Moderate ramp up then hold to allow soft glass to settle. Soak even longer to reduce bubbles.
here is data
2. Heating II:	200		1370	20
Slow ramp to squeeze out trapped air.
here is data
3. Heat to Forming Stage:	400		See Forming Chart	Desired Effect
Heat glass to forming temperature. Consult Forming Chart.
here is data
4. Anneal I:	9999		950	60
Fast ramp down then hold to thoroughly equalize temperatures.
here is data
5. Anneal II:	150		800	10
Slow cool through sensitive zone, then hold to equalize.
here is data
6. Cool Down:	300		100	0
Moderate ramp down to minimize thermal shock.

Slumping Chart (For projects up to 3/8" thick)
Segment	Rate		Temp	Hold
	(°F per Hour)		°F	(minutes)
1. Heating I:	150		300	15
Slow ramp up to 300º then hold to equalize temperature of everything in kiln (minimizes thermal shock).
here is data
2. Heating II:	300		1100	20
Moderate ramp to 1100 and hold.
here is data
3. Heat to Forming Stage:	150		See Forming Chart	Desired Effect
Heat glass to forming temperature. Consult Forming Chart.
here is data
4. Anneal I:	400		950	60
Moderate ramp down then hold to thoroughly equalize temperatures.
here is data
5. Anneal II:	150		800	10
Slow cool through sensitive zone, then hold to equalize.
here is data
6. Cool Down:	300		100	0
Moderate ramp down to minimize thermal shock.

Forming Chart	Definition	Forming Temp
Slump	Glass softens and slumps to take the shape of a selected form or mold. Note: small molds may need higher temperatures and/or hold times.	1215º-1250º F
Tack Fuse	Separate glass layers are fused together with little deformation beyond softening of edges.	1350º- 1370º F
Contour Fuse	Separate glass layers are fused together, edges are soft and rounded, project surface retains the degree of dimesion desired by the artist (any degree beyond Tack but not yet Full fused).	1400º-1450º F
Full Fuse	Separate glass layers are completely fused into a single uniform layer, top surface is smooth and void of dimension or relief.	1460º-1480º F

<

4-Segment Firing
For faster firing: you may wish to accelerate or simplify firing for small or less consequential projects. If so, in the Fusing Chart, eliminate segments 2 and 6. In the Slumping Chart, eliminate segments 1 and 6.

Bubble Squeeze To Reduce Bubbles Between Glass Layers To reduce bubbles between glass layers, fire to encourage a very slow relaxing of the layers, “squeezing” air outward to the edges for release. As the fusing chart indicates, we recommend a lengthy hold at about 1150º F, then a slow ramp up to 1370º F. Increase the effectiveness of your “squeeze” by lengthening your Hold in Segment I and slowing your Rate in Segment 2. Bubbles are best avoided in the design stage. Large areas of uninterrupted layering invite them. For example, a 10 x 10-inch sheet atop another 10 x 10-inch sheet leaves no easy avenue of escape for the air between glass layers. Alternately, a 10 x 10-inch sheet topped with four 5 x 5-inch pieces provides seams to vent trapped air. Design to avoid bubbles for the best prevention.

Find this information and more on the System 96 web page.  

How to use glass casting molds, tutorial

This tutorial came from GlassCampus.com and is full of excellent information.   Check out their website for many more informative tutorials!


Using Casting Molds

PREPARING THE MOLD
Carefully clean the mold to remove any dust and
scrub out any remaining kiln wash from previous
firings.  Single-use kilnwash like “Hotline” is
preferable to multiple-use kilnwash like “Bullseye”
because it’s easier to scrub out.  An old used
toothbrush is an effective tool for removing kilnwash
or a bristle brush on a Dremel will speed up the job.
Prepare the mold with 3 or more coats of thin kiln
wash.  More thin applications are better then few
thick coatings.  Be careful to not apply so much kiln
wash that you fill in all the detail in the mold.  Don’t
just coat the inside part of the mold that will be filled
with glass, but also coat the top upper surface.  Any
small pieces of glass that are left on that surface
will become permanently embedded into the mold if
you don’t.

FILLING THE MOLD
The glass level will drop as it melts into the mold.
Take care to be sure you  have enough to fully fill
the mold.  The smaller the pieces of glass you use,
the less it will sink.  On average, the finished
casting will be about half the depth of the loose
filled mold.  Because the glass level drops, you may
prefer to fill part of the mold with a pieces of glass
stood vertically to provide the extra glass needed to
fully fill your mold.

FRIT & POWDER
Glass powder and very fine frit doesn’t stay
transparent but will turn slightly opaque making the
finished casting looking more like alabaster then
glass.  Some attractive special effects can be
achieved by putting small amount of glass powder
in the details of the casting and filling with larger
pieces of a different colour.

FIRING SCHEDULE FOR CASTING (COE 96)
1. 800 dph to 1475°F hold 20 min
2. FAP to 960°F hold 30 min
3. 600 dph to 300°F OFF

FINISHING THE CASTING
Your casting will have some spikes along the
edges.  You can cold finish to remove them – either
by hand or with a grinder or wet belt sander.  The
casting will also have some texture from the mold.
You can remove the texture and smooth off the
scratches from cold finishing by turning the casting
over and returning it to the kiln to fire polish.

FIRING SCHEDULE for FIRE POLISH
      1    500 dph to 1000°F hold 20 min
     2  1500 dph to 1300°F hold 5 min
     3    FAP to 960°F hold 60 min
     4    500 dph to 200°F OFF min

The above firing schedules are for COE 96 glass.
For COE 90 add 20°F to all top temperatures.
For float glass add 50°F.

Creating a fused glass bowl with a steel fusing ring, then slumping in a mold, video

This video is shows how to make a fused glass plate by first using a steel ring and then slumping in a mold.  You will see that the finished piece didn't work and the glass artist explains what he did wrong.  Excellent information!

View the video here!

Detailed glass casting information

We found this detailed information on creating molds for glass casting on http://www.digitry.com/glasskitchen/5castcorn.html by Susan J. Longini and Mary Bayard White.  It has a lot of great information for any glass artist interested in learning glass casting!  

Finished corn, billet and frit

CAST CORN à la Cire Perdue

The Bay Area natural foods tradition prompted us to prepare corn on the cob glass multiples by casting rather than genetic modification. The cire perdue (lost wax) process involves making a negative mold of the corn, pouring a wax positive into it, investing the wax, melting the wax out and melting glass into the investment. The molds that offer the best detail for pouring over 4 waxes are often rubber molds with a plaster backing. They are time consuming and expensive to make, but worth it if one wants to make many multiple waxes. Silicon and dental alginate molds hold up for about four pours and provide a less costly and faster alternative, as in this situation. Two recipes for making the wax corn, and two mold recipes for casting the glass corn follow. Special thanks to Mitchell Gaudet for his casting/cooking wisdom.


Cire Perdue Corn Positive à la Silicon Mold

This recipe is inexpensive, durable, quick, and can produce approximately four decent waxes. The mold is temporary.

Ingredients and Equipment
One cob of corn with a hole drilled through stem and threaded with string
Razor blade and 20 hat pins
5 cups bees wax or Brown Victory wax, enough for four corns
Pot to melt wax in: double boiler, crock pot, preferably with temperature controller
pouring cup for wax
2 tubes GE Silicon Rubber I (not II) and tube dispenser
2 tablespoons Dawn liquid soap
4 cups water

 

Steps
1. Attach cob of corn so it can hang securely from hook or beam. Hang mold without touching anything.
2. Dissolve 2 TB Dawn liquid soap into bowl of water and squirt out entire tube of Silicon Rubber into bowl of water.
3. Thoroughly mix with hands, immediately pat onto the corn until evenly covered to 1/2" in depth. Mix up a second tube of silicon immediately and apply if silicon layer is not at least 1/2" thick. Use second tube of silicon if necessary to cover the corn to the right thickness.
4. Cure 24 hours. Some silicons need longer.
5. Use razor blade to cut down the side of the wax corn through silicon about 4" so the corn cob can be carefully pulled out of the mold.
6. Pin up sides of mold with hat pins placed in opposite directions.
7. Heat up wax in double boiler or crock pot. Do not allow it to boil. Make sure no water is in the wax.
8. Pour wax, (melted at 212°F or below) into corn mold. Pour out excess wax when wall is 3/4" thick.
9. When wax has cooled, remove from mold Wax Corn on the cob. Wait till wax is very firm on inside, at least four hours unless quite cool environment.
10. Remove from mold and pour another corn. Repeat until four corns are cast.

OR

Cire Perdue Corn Positive à la Alginate Mold

Wax Corn a la Alginate mold: very immediate, can cast organic material, will not irritate skin, more detail, very tear able mold, harder to handle, will shrink and distort in several days, needs refrigeration. Several types of alginate are easily available, but none are inexpensive materials: Dental Alginate, Dermagel, Hydrogel N.

Ingredients and Equipment
One cob of corn with a hole drilled through stem and threaded with string
Razor blade and 20 hat pins
5 cups bees wax or Brown Victory wax, enough for four corns
Pot to melt wax in: double boiler, crock pot, preferably with temperature controller
Pouring cup for wax
About 4 cups Dermagel or other preferred brand
Bowl to mix alginate
Water and measuring cup
Plexi tube hinged on side or mold made from plastic containers and duct tape

Steps
1. Attach cob of corn so it can hang securely from hook inside the plexi cylinder or plastic mold. Allow about 1 1/2" clearance on all sides.
2. Start wax heating.
3. Check volume, measure enough Dermagel in bowl to fill the volume and add water to creamy consistency. One part to 1-1/2 part water or the proportion listed in the alginate you are using. Alginate will stay lumpy.
4. Mix fast with hands and pour into mold. Let set about ten minutes.
5. Open mold and cut down the side of alginate just enough to pull out corn cob.
6. Pin up the side with hat pins and pour wax into corn mold. Pour excess wax out when wax wall is at least 3/4" thick.
7. Remove wax corn from alginate mold and pour as many as possible until mold breaks down.
8. Store Alginate mold in refrigerator, good way to cool wax.

Sources
-Hydrogel N Polytek, 610 559-8620
- Dermagel: Douglas and Sturgess, Inc. 1888-ART-STUF www.artstuf.com
-Victory Brown Wax www.Fremansupply.com

Measuring amount of glass needed for glass casting mold
Once the wax positive is made, and before putting any mold material on the wax corn, calculate the volume of the positive by submerging the wax in water jar, and calculating the volume of glass needed by water displacement. Record that volume for use in calculating the amount of glass needed to fill mold. If using frit, specific gravity of the displaced water can be used to calculate weight of glass to be used. Add 1/3 more glass if using flower pot drip method.

Glass types
Either solid glass or frits may be used. The tinted Bullseye transparent yellow is perfect for corn. A mixture of clear opaque and transparent frits will give a more mottled corn effect, and have less transparency.




Wax positive and starting to apply Mold Mix 6

CAST GLASS CORN MOLD RECIPES
Two glass casting molds: Mold Mix 6 and Plaster/silica/refractory mold

Mold Mix 6 glass corn mold with flower pot drip fill
using glass billets

Mold Mix 6 is a high alumina shell material used primarily for casting metal. It can be applied with little mess, is excellent for small solid shapes like corn, and gives the glass a shiny surface.

Ingredients and Equipment
Wax positive
Latex or vinyl gloves
OSHA approved mask
Hair spray
Food coloring
Wood board 4"x4"
Metal grid
Pan of water to catch wax:
Mold Mix 6 (Luminar) 2 cups in sealed airtight container
Second airtight container to put half of the MM6
Open mouth glass jar with 1cup water, for washing brush
Stiff brush 1/2 ", not nylon.
6 cups beach sand
Braun hand blender
Propane and blow torch
Kiln furniture
4" flower pot
6-7" flower pot
High temperature gloves
Bullseye Glass tinted billets: yellow, a little less than one half billet per corn

Steps
1. Touch up the wax corn positive so surface is exactly as desired and construct a 2" x 1" reservoir out of wax and attach to the stem. Calculate the amount of glass needed to fill the corn mold. If using Bullseye tinted billets, do this by replacing same volume of wax corn with volume of glass. Then add 1/3 more glass by volume to account for glass left in flower pot.
2. Attach the wax positive reservoir to a wooden board so it stands up and can be moved around easily. Very important to attach it securely so it will not break off in the mold making process, which takes 3-5 days. Spray with light mist of hair spray.
3. Whip up about 1 cup of the MM6 in a separate seal able container with Braun hand blender.
4. Start to paint onto the wax corn, being careful to apply thinnest layer possible, and let dry until hard. MM6 is
inherently lumpy, so just work with the lumps to create a smooth paper pulp like surface.
5. Continue applying layers of MM6 every day until 4-6 layers are applied. Total thickness will be no more than 1/2".
6. Each layer may be colored with a little food coloring to distinguish layers. Make sure the layers near the
bottom reservoir lip are even and at least 1/2" thick. Do not apply next layer until first is dry. Keep layers as
thin as possible
7. When mold is hard and dry after last coating, take mold off the wooden board and set on metal grid over a pan of water. Best to do outside with good ventilation. Victory wax will burn with sooty deposit.
8. Use large propane hand torch, the kind used in a hot shop, to start melting out the wax.
9. Slowly heat the bottom near the reservoir so the wax begins to melt. Do not start at the top of the mold because the wax will seep out through the MM6. As it is heated, the mold will turn black and sooty. Try to avoid setting the
wax on fire by holding the torch far away. Continue to heat from bottom up. Melting process may take up to
half hour.
10. Slowly move up the mold and melt out wax from bottom of mold near the opening. Beeswax melts out more easily and has fewer fumes than Victory Brown wax, however it is more brittle to work with and a little bit more of
a challenge to touch up.
11. When wax is completely melted out of mold, increase the heat and torch the mold until it is red hot and turns from black to white again. It will then feel like egg shell. Let cool. Hold up to a light and check for cracks. Patch with another layer of MM6 if necessary. It has not been necessary to reheat with the torch after patching.
12. Pour thin solution of Bullseye shelf primer into MM6 mold with quick motion, fill it up and pour out immediately.
Pre-fire mold to 600F if filling with frit for firing. If using flow pot drip method, the pre-heat is not necessary.
13. Prepare 4" flower pot large enough to hold the glass and use pliers to grouse out the hole in bottom to make sure glass can flow easily. Place glass in flower pot.
14. Place mold in large 6" flower pot and fill with sand so sand is around the entire mold to be filled
15. Build structure of kiln furniture (can slice up broken kiln shelves into 1" strips) so that flower pot is about 1" higher than mold and hole is directly above the hole in mold. If the reservoir is at least 2" diameter, there is plenty of room for the glass to flow down in a circular movement and fill the mold. Do not support the flower pot on the mold, make a scaffolding of kiln furniture.
16. Start firing. When mold has reached 1550F for one hour, check to see if glass has filled mold. If not, maintain 1550F temperature until filled. Spoon more glass into the hot flower pot while in the kiln if necessary. When glass has filled, bring down kiln quickly to annealing temperature. Pull hot empty flower pot when mold is filled, because, sometimes the stream of glass from the pot will cause cracking in glass as it cools.
17. Cool and wait 24 hours after removal from kiln. Break away mold off carefully. With shelf primer is applied to the inside of the mold, the glass usually comes off clean.

Sources
-Mold Mix 6 (formerly Luminar)
ZRCI
PO Box 489
Florida, NY 10921
845 651-2200 www.zrci.com
Temperature Controllers: Digitry Company, Inc. www.digitry.com
-www.bullseyeglass.com

Firing Schedule for both Mold Mix 6 and Plaster/Silica/Refractory Mold

step	Step Time	Temp °F
1	1 min	200
2	6 hr	200
3	4 hr	1000
4	2 hr	1000
5	2 hr	1550
6	3 hr	1550
7	1 min	1250
8	2 hr	1250
9	1 min	1000
a	1 hr	970
b	5 hr	920
c	1 hr	920
d	1 min	800
e	1 hr	800
f	5 hr 30 min	250

Plaster/silica/refractory mold with reservoir and frit firing

This is a type of mold that releases easily, is tough and has little cracking and flashing. Very soft dental plaster can be used for the first layer. It is harder to make than MM6 mold, but assures easy release and for more complicated shapes, is more applicable.

Ingredients and Equipment
Wax positive
Latex or vinyl gloves
OSHA approved mask
Hair spray
2 lb silica, at least 120 mesh, some finer
1 lb 30 minute casting plaster
Plastic bowl or bucket to mix
1 lb refractory cement: approx 60% alumina, any brand available.
Plastic wrap
Wooden board 5" x 5" approx.
Wall paper steamer
Pan with water to catch wax
Metal grid to hold mold while steaming
Aluminun foil
Bullseye Frits: #1 or #2 clear with no more than 10% opaque and transparent yellow powders mixed in when clear
glass is moist.
Bowl to mix frits and spoon or spatula
4 cups vinegar

Steps
1. Attach wax reservoir to wax corn so it is very stable. Very important part, because frit will be loaded into reservoir when kiln is at1550F.
2. Attach wax corn and reservoir to wooden board and spray with Hair spray
3. Mix 1 part plaster and 2 parts silica 40% to 60% and sift into 1-1/2 part water.
4. Paint on first layer with brush, or use hands.
5. Continue to cover wax with plaster/ silica mixture until 1" thick all around. Let set one hour.
6. Mix up refractory cement with water so forms ball when squeezed. Pat over plaster/silica until a 1/4" to 3/4" shell is
created. May need to hold refractory in place with tin foil or plastic wrap. Can put hair pins in wax in order to control even thickness of the walls of the mold.
7. Pull out any pins before the refractory drys.
8. Steam out all wax from mold. When top of the mold is hot, usually all wax is gone. Use aluminum foil to cover mold and direct steam.
9. Let dry three to four days.
10. Set up in kiln so easy to reach and fill when hot. Use kiln furniture.
11. If using frits, measure glass and fill mold and reservoir. Turn on kiln and fire.
12. When reaches 1550F for one hour, check to see if mold is filled. If not, maintain 1550F and use large stainless steel spoon to fill until mold is full.
13. Cool and do not break out for 24 hours.
14. Break outside mold off carefully. Be careful when chipping away outside layer. Inside layer should crumble away. Soak in vinegar, then clean with water.

Firing schedule: See Above

Kilns
Top loading kilns with side and top elements work. Ideally kiln will have elements on top, bottom, and sides.

We both use Digitry controllers, have used them for many years, and find them student user friendly and good for our purposes.

Information on fusing recycled glass

Fusing Recycled Glass

Material:  Recycled Glass

Issue: It is very simple to fuse recycled container glass to make tiles and relief plaques.  However, information on raw material characteristics, temperature profiles, and operational issues has not been widely disseminated.

Best Practice: At temperatures considerably below melting, particles of metal, ceramics, or glass begin to bond through a process called sintering.  Sintering of soda-lime glass begins at about 1250° F. Sintering can be used to create solid glass objects by heating glass particles to above the sintering point and holding at that temperature until a dense body forms.

The basic steps are described below:

1)      Obtain a mold that will withstand temperatures of at least 1600° F.   Coat the mold with a release. Commercial “shelf paints” are available.  A mixture of 40% kaolin and 60% alumina hydrate also works well.

2)      Fill the mold with glass pieces. Glass of any size can be used.  However, the most consistent success has been obtained with glass that has been crushed to a uniform shape and screened to a size 16 mesh and finer.  There is a trade-off here between glass grain size and cleanliness.  It is easier to obtain a glassy, translucent product with larger grain sizes, but smaller grain sizes minimize contamination.

3)      Fire the kiln to fusing temperatures.  For green or amber container glass, the following schedule is a place to start:

      500°F/hour                                to 1100°F         
(organic contamination should be gone by this point)

      1000°F/hour                              to 1600°F                                    
(or go as fast as the kiln will rise)

      soak 5 minutes                          at 1600°F                  
(this is the critical time & temp – experiment)

      Natural cooling                          to 1020°F

      Soak 15 minutes                        at 1020°F           
(may need longer soak for thick or uneven pieces)

      70°F/hour                                  to 950°F

      Cool 300°F/hour                        to 250°F

      Open kiln to cool to ambient

Each kiln acts differently.  The maximum temperature that works best in a particular kiln may be anywhere from 1500 to 1600°F.  Fusing can also be done in cone kilns.  Fire at medium speed until organic burn-off then at maximum speed and try cone 010, 011, 012, and 013.  If the fused tiles have bubbles or bloat, it may mean that organics need more time to burn out, that other contamination is present.  Try soaking at 1100°F for 10 to 20 minutes.

Container glass “devitrifies” very easily.  This means that the glass changes from a glass back into a crystalline material, with two results: the glass takes on a matte finish; and it becomes much stiffer. Slower temperature profiles and long soaks appear to make devitrification worse.  A large amount of direct radiant heat (as from top-mounted heating elements) appears to promote devitrification, as well.

The best strategy for starting recycled glass fusing is to find a source of crushed glass that is reliable and consistent.  Then develop a matrix for an experiment.  Combine different colors and different grades, and fire with different ramping temperatures from 1450°F to 1600°F.  Most of the early experiments will fail, but patience will be rewarded.

Either side of the fused glass product can be chosen as the featured side.  The side exposed to the air will have a graceful “slump” and will probably be glossier than the other side.  The side that was in the mold can be made to take on any type of relief.

Virtually any clean glass can be fused at the right kiln temperatures.  Although making fused glass products as artwork or in small-scale production has been growing over the years, most artists and product developers have stayed away from using recycled glass because it is a more challenging material than some of the glass designed and manufactured for fusing, like Bullseye Glass.  However, some small businesses, like this one in Seattle, are successfully manufacturing glass tiles using this type of process.

Implementation: These instructions can be used with the Best Practice Permanent Molds for Fusing Glass to begin experimenting with glass fusing.

Benefits: This process is accessible to anyone with a ceramics kiln capable of 1600° F.

Application Sites: Crafts shops, small businesses.

Contact:  For more information about this Best Practice, contact CWC, mailto:info@cwc.org.

References:

Richerson, David W., Modern Ceramic Engineering - Properties, Processing, and Use in Design, Mercel Dekker, Inc., 1982.

For a general discussion of glass fusing and moldmaking:
Lundstrum, Boyce, Glass Casting and Moldmaking, Vitreous Press, 1989. The book is available on Amazon.com or from many ceramics and glass supply stores.

For more about issues related to glass devitrification, see CWC report Densification, Crystallization,

and Sticking Behavior of Crushed Waste Glass Sintered in Refractory Molds with Release Agents, CWC, 2000.

Issue Date / Update: April 2000