Cone 04 temperature
Orton cone 04 bends at 1945 °F (1063 °C) at 108 °F/hr and 1971 °F (1077 °C) at 270 °F/hr. It sits in the bisque & earthenware range — cone 20 of 38 on the chart, counting up from 022.
108 °F/hr · 60 °C/hr
1945 °F1063 °C
Medium — the rate most charts quote
270 °F/hr · 150 °C/hr
1971 °F1077 °C
Fast — typical of a quick electric firing
Orton self-supporting regular cones; rate measured over the last 200 °F of the firing. Source: Orton °F chart; °C converted. Cones measure heat-work, so a controller set to 1945 °F is not the same as firing to cone 04 — put a witness cone on the shelf.
Cone 04 is not cone 4
The leading zero means cone 04 counts down from cone 1 — it's a bisque & earthenware temperature (1945 °F). Cone 4 is 179 °F hotter (2124 °F), in the between the ranges range.
What cone 04 is used for
Bisque & earthenware — The workhorse range for the first firing. Cone 06 and 04 are the two standard bisque targets, and most earthenware and low-fire glazes mature here too.
Convention per Bartlett factory bisque profiles (cone 08/06/04); Orton.
Cone 04 compared
| Comparison | At 108 °F/hr | Difference (medium) | Difference (fast) | |
|---|---|---|---|---|
| cone 04 vs cone 4 | 1945 → 2124 °F | 179 °F (99 °C) | 190 °F (106 °C) | cone 4 is hotter |
| cone 04 vs cone 05 | 1888 → 1945 °F | 57 °F (32 °C) | 60 °F (33 °C) | cone 04 is hotter |
| cone 04 vs cone 03 | 1945 → 1987 °F | 42 °F (23 °C) | 48 °F (27 °C) | cone 03 is hotter |
| cone 04 vs cone 06 | 1828 → 1945 °F | 117 °F (65 °C) | 116 °F (64 °C) | cone 04 is hotter |
| cone 04 vs cone 5 | 1945 → 2167 °F | 222 °F (123 °C) | 234 °F (130 °C) | cone 5 is hotter |
| cone 04 vs cone 6 | 1945 → 2232 °F | 287 °F (159 °C) | 298 °F (166 °C) | cone 6 is hotter |
| cone 04 vs cone 10 | 1945 → 2345 °F | 400 °F (222 °C) | 410 °F (228 °C) | cone 10 is hotter |
Convert
cone 04 bends at
1945 °F(1063 °C)
At 108 °F/hr (60 °C/hr) — medium. Faster firing → the same cone bends hotter. Everything about cone 04 →
Questions
- What temperature is cone 04?
- Orton cone 04 bends at about 1945 °F (1063 °C) when the kiln climbs at 108 °F per hour, and about 1971 °F (1077 °C) at 270 °F per hour. Cones measure heat-work — temperature over time — so the faster you fire, the hotter the kiln has to get for the same cone to bend.
- What is cone 04 in Celsius?
- 1063 °C at 108 °F/hr (60 °C/hr) and 1077 °C at 270 °F/hr (150 °C/hr), converted from Orton's Fahrenheit chart for self-supporting regular cones.
- Is cone 04 the same as cone 4?
- No — and this is the most common cone mix-up. Cones with a leading zero count down toward cone 1, so cone 04 is cooler than cone 4: about 1945 °F versus 2124 °F at 108 °F/hr, a difference of 179 °F. Read the zero as "oh", not as nothing.
- What is cone 04 used for?
- cone 04 sits in the bisque & earthenware range. The workhorse range for the first firing. Cone 06 and 04 are the two standard bisque targets, and most earthenware and low-fire glazes mature here too.
- How far is cone 04 from cone 05 and cone 03?
- At 108 °F/hr, cone 05 bends 57 °F cooler (1888 °F) and cone 03 bends 42 °F hotter (1987 °F). One cone step is not a fixed number of degrees — the spacing varies across the chart.
Firing to cone 04? Claybench schedules the kiln around it.
Clay body, glazes, and firing schedule are matched by cone before a plan is saved.