Challenge: Create a custom snowmobile cargo rack to withstand the rigors of a remote Montana backcountry lodge and ski business.
Altoona Ridge Lodge owner Denison von Maur approached Acuity to create a snowmobile rack to withstand the rigors of his remote, client-based backcountry lodge business. Altoona Ridge Lodge sits 7,600 feet above sea level in Montana’s rugged Flint Creek Range. In the winter, there are only two ways to the lodge: by skis or by snowmobile, the latter of which is the preferred method for most of Denison’s clients. The snowmobiles are loaded with hundreds of pounds of food and gear for lodge patrons and ridden up thousands of vertical feet of untracked mountain road to the lodge. Stock and commercially available aftermarket racks couldn’t survive the punishment, so Denison came to Acuity.
The first step of the process was to determine the actual load being applied to the rack. The loads can be weighed, but Acuity’s engineers realized that shock and fatigue loading from from rough terrain had to be taken into account. Acuity performed analysis using Maple mathematical modeling software to properly choose material, tube diameter, and wall thickness. The next step of the process was to create a basic 3D CAD model of the rear of the snowmobile and design an elegant tube-frame structure that fit. After the rack CAD model was created, Acuity performed FEA (finite element analysis) for both maximum and fatigue stresses to determine if the designed rack would survive. The final step for the Acuity team was to get in the shop to bend and fixture the tubes and weld the rack. The finished rack was then beautifully powder coated by PCS in Missoula and installed by Acuity. Going into its second season, the rack is still going strong!