Kiln Firing Schedules
It's a great idea to start a journal of firing schedules that you can make notes in for each project. This will help you to review your schedules, if you decide you need to make changes. These firing schedules are starting off points to help you develop firing schedules that work in your kiln. Each kiln will fire a bit differently and hold heat differently.
In some kilns, it is helpful to vent when firing to help prevent devitrification from burnoff. When using adhesives or shelf papers, gases or vapors can settle on your fused glass pieces, if there is no way for them to escape the kiln. Venting can be achieved by placing small squares of 1/8" or 1/4" fiber paper between the lid and the kiln during firing or leaving vent plugs out. This little space allows residues to burn off and escape the kiln. It can also help to speed the cooling rate through the devitrification range on the way to annealing temperatures. Make sure that your kiln has ample space all the way around it and that it is not too close to walls or flammable materials. Visit your kiln manufacturer's website for specific information.
Here are some sample firing schedules to get you started:
Assumptions: 2 layers of standard thickness glass (3mm or 1/8") stacked to make a thickness of 6mm or 1/4"
These firing schedules are fairly conservative, so you shouldn't have any breakage. However, please note that these firing schedules are just general guidelines and recommendations made by No Days Adhesives. It is up to the user to take into account their glass fusing setup and design, materials used and kiln being used to yield their desired results.
dph = degrees per hour (Fahrenheit)
AFAP = as fast as possible, represented by 9999 when programming your kiln
min = minutes
FULL FUSE: This firing schedule is for a full fuse, meaning that the layers of glass will melt together and have no texture left.
| Full Fuse | ||
| 250 dph | 600º F | 45 min |
| 250 dph | 1000º F | 60 min |
| 250 dph | 1100º F | 10 min |
| 50 dph | 1250º F | 20 min |
| 500 dph | 1480º F | 10 min |
| AFAP | 960º F | 45 min |
| 100 dph | 800º F | 0 min |
| 200 dph | 700º F | 0 min |
| 400 dph | 100º F | 0 min |
SOFT TACK or "Contour" Fuse: This firing schedule is for a tack, soft or "contour" fuse. The fused piece will have a slight texture, but the edges will be very rounded
| Soft Tack or "Contour" Fuse |
||
| 250 dph | 600º F | 45 min |
| 250 dph | 1000º F | 60 min |
| 250 dph | 1100º F | 10 min |
| 50 dph | 1250º F | 20 min |
| 500 dph | 1440º F | 8min |
| AFAP | 960º F | 45 min |
| 100 dph | 800º F | 0 min |
| 200 dph | 700º F | 0 min |
| 400 dph | 100º F | 0 min |
TEXTURAL TACK FUSE: This firing schedule is for textural tack fuse and is used in creating fused glass mosaics. The fused piece will be highly textured.
| Textural Tack Fuse | ||
| 250 dph | 600º F | 45 min |
| 250 dph | 1000º F | 60 min |
| 250 dph | 1100º F | 10 min |
| 50 dph | 1250º F | 20 min |
| 500 dph | 1375º F | 7 min |
| AFAP | 960º F | 90 min |
| 100 dph | 800º F | 0 min |
| 200 dph | 700º F | 0 min |
| 400 dph | 100º F | 0 min |
POWDER WAFER BURNOUT SCHEDULE: The following three segments should be the first segments in a firing schedule for burning out the binders in the No Days Powder Wafers slowly to prevent distortion of the shapes. It also helps to cut back on the smell of the binders burning out.
| Powder Wafer Burnout - add to beginning of other schedules when using No Days Powder Wafers |
||
| 150 dph | 300º F | 45 min |
| 250 dph | 600º F | 45 min |
| 250 dph | 1000º F | 45 min |
SLUMP SCHEDULE: This firing schedule is for a slump schedule. After using one of the above schedules to fuse your pieces together, you're ready to give it shape by placing it in a mold. Make sure that the glass is not bigger than your ceramic mold, or you can potentially break your glass, your mold or both while firing.
| Slump Schedule | ||
| 250 dph | 750º F | 10 min |
| 250 dph | 900º F | 30 min |
| 300 dph | 1150º F | 15 min |
| 300 dph | 1250º F | 30 min |
| AFAP | 960º F | 90 min |
| 50 dph | 800º F | 0 min |
| 100 dph | 700º F | 0 min |
| 300 dph | 100º F | 0 min |
dph = degrees per hour (Fahrenheit)
AFAP = as fast as possible, represented by 9999 when programming your kiln
min = minutes
For more information or questions regarding firing schedules, please e-mail Carrie at info@nodaysadhesives.com.