To fasten a layer of 4 logs on top of the layer beneath it we used 10 mm rebars which we cut into 45cm, 50cm and 55 cm lengths. We drilled 12mm holes at 50 cm intervals into the top layers of logs and drove these pins into the bottom layer with a 6lb hammer.
Simon had just acquired a new industrial quality drill with a 13mm gear chuck and a rotatable D-handle that could handle a 12x460mm Auger bit. I already had an old Honda generator which provided sufficient energy to power the drill.
Where the end of the log butted against the adjacent log we also drove in a pin horizontally. One layer of 4 logs thus contained about 4 + 2(20) + 2(14) = 72 pins. For 15 layers we thus anticipated using in the region of 1000 pins. This is a little exaggerated as we did not drive in any pins where the gaps for the windows and doors were planned.
This all sounds very straightforward, but wielding a 6lb hammer to drive this length of pin into wood requires strength, stamina and coordination. Siya and Dumisane quickly developed into excellent hammerers. One of them would take turns in following Simon’s holes that he had just drilled.
