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

Design of Javalina Key Chain
List of Supplies Wax Blocks Mixing Cups Stirring
Sticks 635 Thin Epoxy Resin 31 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 Ease was
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