Elmer's Glass Kiln manual Lost Wax Burnout, Overview, Sample Program, Cone

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Open the door ½” to vent the kiln if your kiln does not have vent holes.

China paints will crack or peel if ap- plied heavily. Apply several light coats in- stead, firing between each, until you get the shade you want. Not all china paint colors reach maximum color saturation at the same temperature even when fired on the same ware. So you must know which col- ors you should fire first at higher tem-

peratures to prevent burning out the original colors in later firings. For example, reds mature at a lower temperature than other colors and are fired after the other colors have been fired. Reds and yellows should not be fired side by side. Colors also mature at a lower temperature on ceramic pieces than on porcelain or hard china. Check the overglaze manu- facturer’s literature for information on which cone to use with each color and type of ware.

Vent the door during the first hour of firing. If your kiln has a vent hole, leave it open during the entire firing. Allow kiln to cool to room temperature before opening the door.

Temperature Equivalents For Orton Self-Supporting Pyrometric Cones

 

 

 

 

Cone

Cone

Self-Supporting Cones

Pre-Fire

Number

 

 

 

Color

Heated at:

27° F

108° F

270° F

 

 

Per Hour*

Per Hour*

Per Hour*

 

022

1087

1094

Green

021

1112

1143

Fuschia

020

1159

1180

Orange

019

1213

1252

1283

Yellow

018

1267

1319

1353

White

017

1301

1360

1405

Pink

016

1368

1422

1465

Light Blue

015

1382

1456

1504

Violet

014

1395

1485

1540

Gray

013

1485

1539

1582

Green

012

1549

1582

1620

Fuschia

*Rate of temperature increase during last 90 - 120 minutes of firing. Tables by courtesy of the Edward Orton, Jr. Ceramic Foundation.

Lost Wax Burnout

Caution: Only kilns with vent holes are designed for lost wax burnout. However, you can use a kiln without the vent hole provided that you open the door ½” during venting.

Caution: Always use a wax tray.

Caution: If your kiln’s heating element is embed- ded in the floor of the firing chamber, place the metal wax tray on 3 or 4 - ½” posts inside the kiln. This prevents the element from possibly shorting out against the tray.

Note: These instructions apply to injection wax that melts at 200°F, not pattern waxes and plastics that melt at higher temperatures. If smoke appears dur- ing wax elimination, turn off the kiln. Smoking wax means the kiln fired hotter than 300°/148°C.

Overview

Lost wax casting is the process of carving a shape in wax , and then casting that shape in metal. After the wax has been carved, a mold is made of the wax shape. The mold is a nega- tive image of the wax. The wax is later melted out of the mold through hollow channels called sprues.

Lost wax burnout is the process of preparing a casting mold for the melted metal that will be poured into it. The steps in lost wax burnout:

1Melt the wax from the mold.

2Remove wax from the kiln before raising the tem- perature higher than 300°F/148°C.

3Harden the mold at high temperature.

4Maintain the mold at the casting temperature rec- ommended for the type of metal that will be poured into the mold.

Caution: Prevent wax or carbon from contacting the kiln’s walls and elements. Carbon build-up in- side a kiln ruins the interior. Carbon conducts elec- tricity and causes elements to short circuit. Damage to elements from contact with foreign materials is not covered by warranty.

A Sample Program

See your digital controller instruction manual to enter this program:

 

Rate

Temp.

 

Segment

°F/°C

°F/°C

Hold

1

500/277

300/148

01.00

2

500/277

1350/732

01.00

3

450/250

800/426

02.00

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Contents Page Contents IntroductionSafety Important Safety RulesWhere to Locate the Kiln Setting Up the KilnElectrical Installation Transporting the KilnAccessories Basic OperationImportant Guidelines Place Ware on a Protective Shelf Loading the KilnOptional Glass View Port Applying Glass Separator or Kiln WashVenting the Kiln Using Ceramic Fireclay PostsSilver & Gold Clay Drying TimeRate, Temperature, Hold Cooling TimeFusing Compatibility Test Glass Fusing & SlumpingHow to Cut Glass Annealing RangeCleaning Gluing the Glass Firing the GlassPreparing the Copper Decorating the CopperPyrometric Cones Ceramic OverglazeFiring Enamel Loading and Firing OverglazeSample Program Lost Wax BurnoutOverview ConeSilver Clay Firing MistakesBurnout Instructions GlassCeramic Overglaze Kiln Repairs Kiln MaintenanceTrouble-Shooter Replacing the Thermocouple Replacing a Relay or TransformerReplacing the Temperature Controller Replacing the Firing Chamber