Abstract: Sun Valley Expo-axis single-layer grid of nodes in large quantities, the different space angle bars, each bar height difference exists in the node with the wrong side, leading to similar to each node is not the same characteristics. Deepening design of highly manual and error is difficult to check and find errors. In this paper, the building of the Expo Axis Sun Valley relies on a complex spatial structure of the glass curtain wall for connection to single-layer structure and rectangular pipe grid conducted a study of solid modeling. The "nodes together adjacent surface normal vector" principle put forward the rectangular cross-section steel tube in free space positioning methods and reasonable on the surface, and the method through the computer program to achieve three-dimensional solid model of the automatic generation and evaluation capabilities, thereby increasing the efficiency of the design to circumvent the plot error, for the promotion and application of a similar structure to lay the theoretical and design basis. On this basis, to simplify the model and refined model of the comparative analysis, sum up their scope of application. Finally, the curtain wall of glass cutting was geometric analysis and the preparation of auto-cutting process.