For details on the experimental objectives, see Hals / Icelandic 5 - Furnace Construction
Ore : 31.8 kg DD 1 Analog (48% Fe content)
Charcoal : 49 kg (graded fuel)
Time : 5 1/2 hour main sequence (plus 1 hour pre-heat)
|At the beginning of the smelt sequence, showing the air system layout.|
Our test furnace is dug into a bank rather than raised above the surface as at Hals. The V shaped slot is here lined with concrete blocks to retain the earth bank. The size of the slot was dermined by the space required to hold our Viking Age style iron smelting bellows.
|Later in the smelt, tapping off excess slag|
Needing to tap slag illustrates one potential problem with our suggested Hal's based layout. With the bellows in the slot, how do you get access to the front of the furnace for tapping? At the very least, the bellows would have to be connected to the tuyere via a short length of hose. This made of leather?
|The hot bloom during initial consolidation with hand hammers, which also serves to knock off any remaining slag 'mother'.|
Bloom : 13.8 kg
Yield : 42 %
|Secondary compression, then cutting, under the hydraulic press. |
|The roughly compressed pieces.|