Apr 20th, 1:00 PM - 4:00 PM
Log Cutting Apparatus Design Analysis
Dr. Rudy Eggert
Our senior design team from the College of Engineering has been selected to design and build a tool that will assist in producing window notches in pre-manufactured logs. Currently, to make a notch, three cuts are made freehand using a chainsaw Two of these cuts are short cross cuts, which are relatively easy to make. The third is a long rip-cut, and is much more difficult. The current process is not accurate and has several safety issues. Our team designed an apparatus which provides a guide so that the difficult rip-cut is not made freehand. This solves the primary customer issues, resulting in a safer, quicker, more accurate cut. Our team has fabricated a full scale prototype from this design. We have determined the most catastrophic mode of failure to be yielding of the axle for the chainsaw attachment. Due to the complexity of the design we are unable to analytically determine the amount of force on the axle. Our current research will consist of physically verifying the strength of this pin. This will be accomplished by suspending the apparatus, with a chainsaw attached but not running. We will then add successive amounts of weight to the end of the chainsaw. Since the maximum force that the chainsaw can undergo without binding is 11 pounds, weight will be added from 11 to 33 pounds, demonstrating a safety factor of three for the strength of the axle. After each amount weight has been applied, a visual inspection will be done to look for localized yielding. We will also be analyzing the design to see if there are any areas that can be improved upon. This will be accomplished by actually using the prototype and confirming that it acts as predicted. We will also compare the accuracy of cuts made with the apparatus to freehand cuts.