TAMUK Space Research Team at JSC

1. Javalina Key Chains Dept of Mechanical & Industrial Engineering, TAMUK Group Members Nolan Martin, Renato Reynoso, Bryan Steiner, Gustavo Zarate Group Leader Renato Reynoso TAMUK Space Research Team at JSC Description of Project Use various manufacturing processes learned to create carbon fiber/elastomer key chains with the school mascot. • Procedures Followed • Week 1 • Compete all AutoCAD Drawings • Transfer and save all CNC Machines files needed • Optimize G-code • Machine pattern into wax blocks • Mix resin, hardener & chopped fibers • Pour mixture into mold • Let Cure • Week 2 • Remove key chains from mold • Revise & optimize AutoCAD Drawing • Transfer and save all CNC Machines files • Optimize G-code • Try to fix CNC Machine • Week 3 • Machine new pattern into wax blocks • Mix resin, hardener & chopped fibers • Pour mixture into Mold • Let Cure • Remove key chains from mold • Document process Design of Javalina Key Chain List of Supplies Wax Blocks Mixing Cups Stirring Sticks 635 Thin Epoxy Resin 3:1 Epoxy Hardener Regular Hardener RP6442 Rubber Resin Chopped Carbon Fibers 700-NC Mold Ease Equipment 1 CNC Machine Drill Bit 0.125 in 1 Squeegee 4 Pairs of Gloves Safety Goggles 1 Band Saw 1 Box Cutter Design 1 Design 2 Design The design for this key chain had to be optimized several times due to problems in sizing, design, and surface finish. The final design prove to gives us a good finish and good dimensions. The biggest problem in the design was not including draft or taper to ease the release of the molded part. Design 3 Design 4 Manufacturing Process Manufacturing Discussion The manufacturing process was fairly simple. Two resins were tested, 635 Epoxy Resin and RP6442 Polyurethane Resin. The 635 Epoxy Resin was the first one tested. The key chains were stiff and not very flexible. One of the key chains broke when removing it from the mold and another broke after a few days of wear and tear. The RP6442 Rubber Resin proved to have being the better of the two, it was more flexible and the carbon fibers helped to reinforce it. The major problems with the manufacturing process was chopping the fibers into very fine strains and removing the finished part from the mold. When making the first key chains, no release agent was used this made it harder to remove the part. 700-NC Mold Easewas used on the second set of molds. When removing the second set of key chains, a band saw was used to cut a section of the mold, then the mold was broken in half to remove the part easier. Summary We decided to manufacture something that would have a little bit of everything learned and keep a souvenir from the class. We have decided to make carbon fiber key chains with the school logo. We created a pattern that was machined out of wax. The major problems with the manufacturing process was chopping the fibers into very fine strains and removing the finished part from the mold. Mold release was used on an improved mold, but it still had to be sawed in half to remove the cast parts. Part removal issues Wax Molds Epoxy part & mold Epoxy key chain Recommended Improvements to Project Put draft in molds, for easy part removal. Use a stronger material than wax. Use something other than a sunburst for part of the Javelina Final sawed mold Rubber & fiber key chain