By Brent Preston (reprinted from fall 2008 newsletter)
(Sent in by Neil Maclean of Timberlinx)
New technology helps an Indian band realise their vision of a traditional log structure.
The recent history of the Lac Vieux Desert Chippewa of northern Michigan is a story of remarkable progress and growth. Not recognised as an official Indian band until 1988, the Band had less than 100 members and an unemployment rate of 40% in the early 90s, but investment in housing, education and social services at that time laid the foundation for a rapid transformation. The Band has since increased its landholdings from 74 to over 1600 acres, built modern services, a golf course, hotel and gaming facility, and unemployment now stands at just 11%.
With this newfound prosperity, the Band approached Dan Wait of Frontier Builders in 2003 with a plan to rebuild their traditional ceremonial lodge. The building they envisioned would stand on sacred ground in the heart of the LVD Old Indian Village, and would be designed according to the traditions of the Chippewa people. Dan helped the Band create a preliminary design for a massive 75 foot diameter octagonal log building, with centre posts at the four compass points and grand entrance doors on the north and south walls. The 24 trusses would be built of 20 inch diameter pine logs harvested on LVD and adjacent federal lands. Dan gave the band a material list and told them to call him back in two years, after they had felled, peeled and air dried the logs. As construction time neared, Dan and his team at Frontier Builders took the Band’s design concept to an engineer. The results were disheartening. The engineer specified knife plates and multiple steel bolts to carry the massive loads generated in the long spans and large-diameter logs. “He called for something like three tons of steel in all” Dan recalls. This much steel did not fit with what the Band or Dan had envisioned. Dan began to look for alternatives. He met with Neil Maclean of Timberlinx at the 2006 ILBA conference in Montebello Quebec and talked to him about the LVD project. Timberlinx is an internal steel fastening system with excellent tensile and shear capacities. It also has defined mechanical values backed by full-scale testing, something engineers like. At first Dan was a little apprehensive about going with a new technology like Timberlinx. “It’s a little like going from a Model T to a Ferrari” he says. “Knife plates and steel bolts may not look great, but they are reliable, they have stood the test of time.” But when he took the idea of using Timberlinx back to the band, they were immediately enthusiastic. “The band was all over the idea of hidden fasteners, and that’s what sold me” Dan recalls. There was still the problem of engineering, however. Frontier Builders had already paid for the engineering of the structure and was reluctant to pay again. Neil recognised the importance of the project and the size of the potential order, so he offered to pay to have the plans redesigned using Timberlinx. Joe Miller of JFM Design in Galesburg, Illinois reviewed the drawings and developed completely hidden Timberlinx configurations that exceeded the original steel knife plate capacities. In all, 33 Timberlinx connectors were used in each of the 24 trusses. The joints with the highest loads had multiple connectors and hidden splint rings to augment the shear capacity of the Timberlinx. “By using different combinations of full and half Timberlinx connectors, along with threaded rods and split rings, each customized joint configuration could be specified using off-the-shelf parts” says Joe. “Since we could install the connectors in the line of action of all the axial forces, there were fewer shrinkage and load eccentricity issues compared to traditional knife plates.”
In January of 2007, Neil flew to Wisconsin to train Dan’s crew as they began to assemble the trusses. Timberlinx had made a special oversized drilling jig to accommodate the 20 inch diameter logs being used. “The first truss went really well” Neil recalls, “but on the second, we ran into some challenges.”
The custom jig, which guides the drilling location for the 1 1/8 inch diameter holes for the Timberlinx fasteners, was not working precisely on the irregularly shaped logs. Neil, Dan and the Frontier crew worked into the night, modifying and rewelding the jig, until they got it right. “There is always a learning curve with new technology” Dan said at the time. By the next day, the drilling and assembly of the trusses was running smoothly. By the time all the trusses were assembled “the comfort level in using Timberlinx was there” says Dan. He now uses Timberlinx regularly in many of his projects.
The LVD ceremonial lodge is now nearing completion. Ancient Native American aesthetics, traditional log building techniques and modern technology have combined to create a sacred structure on a grand scale.