Dimension |
Planned |
Actual |
Peter Crow |

Wall Thickness | 10 cm | 10+ cm | 20 cm |

Interior Diameter | 25 cm | 25 cm | 30 cm |

Interior Height | 65 cm | 55 cm | 60 cm |

Diameter of air inlet | 2.5 cm | 2.5 cm | 2.5 cm |

Tube Angle | 0 | ~15 deg. down | 30 deg. down |

Inlet Height | 10 cm | 2 cm | 20 cm |

Actual Time | Elapsed Time | Notes |
---|---|---|

1036h | We began with the warm up burn. We began the warm up with some softwood. | |

1051h | T+0:15 | The vacuum we were using for air was set to 1/4 and the opening into the furnace was noted as 10cm. |

1053h | T+0:17 | While the warm-up continued we had our final planning meeting. |

1104h | T+0:28 | The warm-up fire was switched to hardwood. |

1153h | T+1:17 | Finished the first milk crate of hardwood in the warm up fire. |

1214h | T+1:39 | First optical pyrometer measurements. Temperature inside was recorded as 2350°F (1288 C). |

1234h | T+1:59 | Second milk crate of hardwood finished. |

1243h | T+2:08 | Our old vacuum died. Oh well it happens. |

1248h | T+2:13 | New vacuum brought on-line and air flow resumed. |

1314h | T+2:39 | Time to begin the charcoal burn. The hardwood and ash was scooped out. New Air system was made ready. |

1316h | T+2:41 | The Smelter was filled with charcoal (approx. 3.5 Kg), bellows were hooked up and pumping began. |

1324h | T+2:49 | Live coals from the ore roasting were added to the top of the smelter |

1330h | T+2:54 | Remains of fourth kilogram of charcoal added (approx. 0.5
Kg) From this point the smelter was stirred/poked from time to time and small amounts of charcoal were added as needed. The experiment records only the time each Kg of charcoal was finished. |

1341h | T+3:05 | Fifth kilogram of charcoal finished. Optical pyrometer measurement gives the internal temperature as 2380°F (1304 C) |

1350h | T+3:14 | Sixth kilogram of charcoal. |

1358h | T+3:22 | Bellows stopped. |

1400h | T+3:24 | Bellows restarted. |

1403h | T+3:27 | Seventh kilogram of charcoal finished. |

1406h | T+3:30 | Optical pyrometer measurement: 2720°F (1493 C) At this point the ore was added. Each charge of ore was added in two steps (each of approximately 0.5 Kg). |

1410h | T+3:34 | Ore charge 1 - part one added |

1414h | T+3:38 | More charcoal and ore charge 1 part 2 added. |

1416h | T+3:40 | Eighth kilogram of charcoal finished. |

1417h | T+3:41 | Ore charge 2 - part one added. |

1422h | T+3:46 | Ore charge 2 - part two added. |

1426h | T+3:50 | Tuyure rodded out. |

1429h | T+3:53 | Ore charge 3 - part one added. |

1431h | T+3:55 | Optical pyrometer measurement 2640°F (1449 C). |

1431h | T+3:55 | Ore charge 3 - part two added. |

1432h | T+3:56 | Ninth kilogram of charcoal finished |

1440h | T+4:04 | Ore charge 4 - part two added |

1441h | T+4:05 | Tuyure rodded out |

1443h | T+4:07 | Tuyure rodded out |

1445h | T+4:09 | Ore charge 5 - part one added. Tenth kilogram of charcoal finished. |

1450h | T+4:14 | Tuyure rodded out |

1452h | T+4:16 | Eyeball estimate of airflow volume was made. It appears that we are pumping 9L/sec (540 L/min) into the smelter. |

1454h | T+4:18 | Ore charge 5 - part two added. It was around here that we realized that the shallow air inlet was in fact giving us the problems we had been hoping wouldn't occur. An attempt was made to "save" the situation. |

1505h | T+4:29 | Attempted to rod out the tuyure again. This time with a hammer and hitting it hard. We attempted to remove the pipe to clear the jam but it wouldn't move. At this time we decided to add a new air inlet on the back of the smelter 45 cm below the top of the smelter (hence 10cm above the base of the bowl. |

1511h | T+4:35 | Back door was holed through and a slag pull was done. |

1515h | T+4:39 | Eleventh kilogram of charcoal was finished. |

1518h | T+4:42 | Another attempt to rod the tuyure. |

1531h | T+4:55 | Another attempt to rod the tuyure. All of these attempts have produced only partial successes. |

1540h | T+5:04 | Tap the back hole again. |

1545h | T+5:09 | Move the bellows to the back hole. Front hole was plugged with clay. |

1548h | T+5:12 | Twelfth kilogram of charcoal finished. |

1552h | T+5:16 | airflow in the water measurement device attached is 4.5->6.5 cm of water. |

1600h | T+5:24 | Thirteenth kilogram of charcoal finished. |

1609h | T+5:33 | Fourteenth kilogram of charcoal finished. |

1620h | T+5:44 | Fifteenth kilogram of charcoal finished. |

1630h | T+5:54 | Rod tuyure |

1641h | T+6:05 | Stop bellows, connect new pipe to back and change bellows |

1644h | T+6:08 | Begin airflow with new bellows |

1647h | T+6:11 | Rod tuyure |

1656h | T+6:20 | Sixteenth kilogram of charcoal finished. |

1704h | T+6:28 | Change to rotary air pump |

1709h | T+6:33 | Seventeenth kilogram of charcoal finished. |

1719h | T+6:43 | Eighteenth kilogram of charcoal finished. |

1725h | T+6:49 | Nineteenth kilogram of charcoal finished. |

1739h | T+7:03 | Rod tuyure |

1749h | T+7:13 | Stop airflow and allow smelter to begin cooling. |