If your building R/C planes from small scale right up to 1/3. This sanding tool is a must. The joints in my 1/3 D7 slide in, no gaps. If your serious then you know gaps are the killer for cyano. You end up with sloppy over glued connections. Tight joints are the best, you only get one shot on the internal pores. Thin CA is the best way to build long lasting joints. This tool is the fastest way to achieve those results. My favorite tool in my hanger!