The Dream Team’s mission is to redesign the ice axe. This tool has been used for decades, but has been rather stagnant in design. The Team saw an opportunity to improve a product that has the potential to increase performance. The focus is redesigning the blade on the mountaineering ice axe. The current axe focuses on a simple design of a singular beak-like pick that is jammed into the snow and ice, which has proven to work, but seems like there is room for improvement. The Team plans to split the pick into two prongs, and chamfer them inwards. By doing so, the opening on the bottom of the two picks will be larger than the opening on the top. In this case, the picks will act like a nozzle for the snow, and create much more drag. In order to comply with the standards of safety The Team has to abide by the European standard, CEN. The dimensions of the blade and the shaft have both to fall within the current product regimen, which we have already based our design on. Through creating proofs of concepts, the team will ensure that the forces that act on the picks are higher than standard, and that they will correlate to a faster self-arrest time. These POCs include a penetration test, a double prong drag test and an adjustable nozzle water test. Our plans for the design and production of this axe are to keep the project under $1000. When the team successfully completes this project, the general mountaineering community will have access to a new axe that will be the standard for years to come.
Proof of Concept
The team has been preparing materials for the proof of concept tests, which will be conducted in late December and early January. Because the tests have not yet been completed, the team does not yet have tangible results to prove that the double-pronged design is better than the standard ice axe design. So far, the team has come up with three different proof of concept tests to evaluate the projected design concept that is presented in figure 1.
For the first PoC test, the team will build a representation of a nozzle to test the effectiveness of different blade separations in adding drag force to the axe. The second proof of concept the team will build involves a representation of a single and double pronged ice axe. These simple models will be used to test differences in penetration depth on an ice block. This will serve as the team’s penetration test. The last PoC test the team will build also utilizes the same models that will be made for the penetration test. The models will be pulled through sand or snow (depending on Northern Nevada’s weather over winter break) using a fish scale to measure the drag force against the granular substance. This test should provide information about the how well an ice axe will bring a mountaineer to rest with the addition of a second prong compared to a single pronged ice axe.
Team Save My Axe’s main goal is to redesign the general mountaineering ice axe. The purpose of this project is to reduce the total time it takes the user to come to a complete stop when in a self-arrest situation. The design is based on a double-pronged blade with an angle between the two blades to create a nozzle-like shape.
The final product for Team Save My Axe will have to abide by certain design specs in order to satisfy the appropriate CEN B rating, which differs from the technical ice axe rating. There are a few design specs that have not been established yet due to the uncertainty of the manufacturing procedure (the distance and angle between blades), but the team has a loose idea of what those parameters should be and can be observed in the detailed drawings. The specifications that have been securely established are as follows: the angle of curvature for each blade will range from 65 to 70 degrees, the length of the shaft will range from 60 to 70 centimeters, the ice axe weight once fully assembled will range from 375 grams and 425 grams taking into account the new design, the materials of the ice axe will consist of aluminum for the shaft and stainless steel for the blades, and a carabineer hole must be included to fit any of the standard carabineers used in the mountaineering sports.
Since the team’s main goal for the project was the redesign of the ice axe head, this was the only part that needed to be fabricated and assembled. The team started by purchasing a block of 1080 steel, square aluminum tubing for the shaft, and press-fit pins for the assembly of the parts. All of the purchased parts can be seen in Figure 1.
Figure 1: Steel, aluminum tubing, and press-fit pins for ice axe assembly
The Mastercam program was written, which would cut the axe head. The steel was then put into the CNC mill at the University of Nevada Reno’s machine shop, and milled for approximately 50 hours. After this process, the team had a milled prototype of the Save My Axe. Figures 2-4 show the axe head in different stages of the milling process.
Figure 2: The axe head being milled in the CNC mill.
Figure 3: The axe head prior to smoothing with the ball end mill for the CNC mill.
Figure 4: The axe head right before the final milling stage.
While the head was in the mill, the team worked to write the Mastercam file to CNC the spike for the axe. The milling of this part would come close to the deadline of the project, so the team wanted a fallback plan and 3D printed the spike for the axe too. Once the head was out of the CNC mill, the team milled the spike so that the 3D printed spike did not have to be used in the final prototype. The team used a metal grinding wheel to sand the corners of the shaft to fit the prototype more appropriately in the users’ hands. Finally, holes were drilled in the shaft, the axe head mount, and the pick to press-fit the mounting pins in. The axe was assembled in the machine shop with accordance to the press-fit tolerances.
When deciding on materials for the final prototype, the team had to make a decision that would fit within the allocated budget. Steel is not the most ideal material for this axe, though the overhead costs for casting the axe head and pick were too high. As such, the team had to make the final prototype out of materials that can be milled. In the future, the team plans to refine the design and make the finalized product out of a hardened 41xx series steel with a different manufacturing process.
Testing and Results
To test the Save My Axe, the team drove to Donner Summit in search of snow. After searching for a snow-covered hill that had the correct gradient and length, one of the team members dressed in snow pants and a jacket to reduce friction and prepared himself to slide down the hill with the axe. A point on the slope was marked to indicate when the user would plunge the axe into the snow. The team also decided to not use feet to slow the slide, even though in a normal self-arrest situation you would do everything to stop sliding. These two control factors in the self-arrest situation helped keep bias out of the test. The user started in the same spot each run and pushed himself off of the starting line with the same amount of force each time. The team member slid on his back until the marked point. The user then turned over and plunged the axe into the snow until he came to a stop as a result of using a proper self-arresting technique. This test was performed for the Save My Axe and a 1965 Chouinard ice axe to compare the stopping distances between the new design and the typical single pronged ice axe design. The team repeated the test ten times for each ice axe.
After many tests, it was apparent that the Save My Axe design slowed the user quicker than with the Chouinard design. Since the user had used the same approach for each test, the margin of error was small and the tests validated the team’s design. The prototype did not fail during the time of testing. Because of the passing results of the tests, the team will keep the main double-prong nozzle design and continue improving the efficiency of the ice axe by slightly increasing the size of the pick and adze. This will be one of the team’s main points of focus since the prototype that was tested was fabricated smaller than the team initially intended.
This product will decrease the self-arrest time of a mountaineer falling down a slippery slope. The results from the preliminary testing show that this axe decreases the self-arrest distance by roughly 16%, which translates to a quicker self arrest time. When this 16% is applied to a larger distance the stopping rate will likely increase too. This change could mean the difference between a mountaineer falling to his death and living to climb another day. Because the self-arrest time decrease was the main focus of the designed product, the team was not looking into a means of making the product easier for the consumer to use. The Save My Axe ice axe is more efficient than other axes on the market currently, which is the main selling point to consumers. Though, into the future, the team plans to change the design to lessen the overall weight of the axe, and thus make packing it into the mountains easier.
After revealing the prototype and displaying the test data and videos at innovation day, individuals mentioned that the prototype seemed to be a vital tool for mountaineers. It was indicated that the Save My Axe was a product that they would invest in once final design is completed and the tool is on the market. As indicated earlier, the main purpose of the team’s design is to arrest a mountaineer in less time and distance. With the final prototype already revealing that Save My Axe performs better than the old design, the team is optimistic that with further research and development the Save My Axe will become the quintessential mountaineering tool into the future.
Table 1: Self-Arrest Test: Chouinard Design vs. Save My Axe
|Test Number||Save My Axe Design Distance (ft.)||Chouinard Design Distance (ft.)|
Meet the Team
Hi all, I am Peter Ho and I am the lead fabricator of Save My Axe. I am originally from Auburn, CA and I attended a junior college called Sierra College in Rocklin, CA before coming to UNR. At my time at UNR, I made Dean’s list most semester and currently still interning at IGT since summer of 2016. After graduation, I plan on joining workforce and possibly going to graduate school if I find the interest.
My name is Richard Long, and I am the proud CFO of Team Save My Axe. I am from Carson City, Nevada. In my time at UNR, I have been on the Dean’s List, sat on the Differential Tuition and Fees Committee for the Mechanical Engineering Department, and served as an intern for The Hamilton Company in Reno. I plan to graduate from the University in December of 2017 with a Bachelor’s Degree in Mechanical Engineering and two minors in Unmanned Autonomous Systems and Mathematics. I soon plan to apply for graduate schools for acceptance into an aeronautics program in Fall 2018. After my second graduation, I hope to work with a large firm. My dream corporation — Raytheon.
I am a mechanical engineering student and the first from my family to go to a four year university. I graduate from the University of Nevada, Reno May 2017. After my second year at the University I became an engineering mentor for incoming freshmen. I am currently employed at Ainsworth Associates Mechanical Engineers. I was born in San Francisco, CA but grew up in Concord, CA in a very close and loving family. After taking many engineering classes I found that I love thermodynamics, and after graduation I plan on pursuing a field that deals with thermodynamics.
Hello! My name is Tony J. and I’m an international student from Tijuana, Mexico. I’m expected to graduate in Spring 2017 with a Major in Mechanical Engineering. I have been the NV PASS Leader for ME 242 for three consecutive semesters and a Pack Leader for EFIT for two consecutive years. After graduation, I hope to either pursue higher education and obtain and Master’s Degree. The goal is to gain a deeper understanding of System Control while also being able to qualify as a lecturer at UNR for ME 242. My true passion is teaching dynamics, but my subject of interest to learn and possibly research is Controls.
I am a Mechanical Engineering student that grew up in Carson City, Nevada. I have accomplished many things academically over the years. So far, I have finished every semester on the Dean’s List. I am currently on track to graduate with a Bachelors in Mechanical Engineering with minors in Unmanned Autonomous Systems and Mathematics in the spring of 2017. During the summer of 2016, I spent my days working with CA Group, a Civil Engineering firm, learning the general drafting process for engineers. After graduation, I plan to find a job in either Control Systems, or gain knowledge in machining and find a job as a Manufacturing Engineer. If all else fails, I plan to further my education through graduate school.
The team would like to thank several individuals for helping to make this project a reality. First, the team thanks our mentor, Dr. Ryan Tung for his guidance throughout the design process and his thoughts during the idea generation phase. Next, the team thanks Tony Berendsen and the entire machine shop. Without their consistent help and expertise, the final prototype of Save My Axe would not have been accomplished. Finally, over the past year, the team received substantial amounts of help from the entire Capstone course team, especially Nicholas Maus. Thank you all for helping us through this amazing year and making our vision a reality!