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Custom Stand Up Paddleboard

2,384 bytes added, 19:05, 11 February 2016
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Two ASTM tests were selected to test for the expected modes of failure in our board. Knowing that the worst failures of the board could either fail from the delamination of the fiber or from brittle fracture, we tested both of these. ASTM D2344M and ASTM D7264M were the two tests we used to test laminate strength and flexural strength, respectively. Each combination of layup was tested with at least 5 samples. This gave 45 samples for each test and 90 samples total. This was done in order to ensure a significance in the [ results of the testing].
After the testing was competed, the data was analyzed through MINITAB, a statistical analysis software. Both interaction plots and main effects plots are shown here. The interaction plots show which combinations work best together. for example, I-foam does not work well with any fiber. This is because during manufacturing, the I-foam did not adhere well to the fiber with our epoxy choice. The main effects plots, also used in the final selection of materials, show which materials significantly affect the measured results. For example, EPS and I-foam both significantly decrease the weight of the board, as they are below the dotted line.
|Image:CompositeLaminarStrength.png|Laminar Strength Results
Strength was a vital component of the selection. As seen in the graphs here, and in the main effects plots, EPS and divinycell are the strongest two foams. Carbon fiber is the strongest fiber with heavy glass close behind.
|Image:TotalWeight.png|Weight Results
As shown both here and in the main effects plot for cost, EPS and light glass are the cheapest materials with I-foam and carbon fiber being the second cheapest materials.
For weight, EPS is the cheapest with I-foam close behind. Both carbon fiber and light glass are approximately equal in weight and less than heavy glass.
Ease of manufacture was decided upon while pressing the samples for testing and while searching for materials in large enough blocks for a paddleboard. As noted earlier, I-foam had trouble adhering to the fibers, and was thus elimated as a possible candidate. Divinycell is not made in blocks large enough to manufacture a paddleboard blank out of, thus it was also eliminated.
After all of the above methods were considered, a decision of EPS foam and carbon fiber was made. Although Divinycell and carbon would have yielded the strongest board, divinycell and carbon are both expensive, and divinycell is not able to be found in large blocks. EPS gave similar strength results, and although carbon was expensive, its benefits in all other categories outweigh the cost of it.
|Image:FEA_Compiled_Results.png|FEA Validation
   Ease After the FEA simulations had been run, the results were put into this chart. By comparing the FEA stress values to the flexural strength of manufacture the material that was decided upon while pressing calculated, we determined the samples for testing and while searching for materials in large enough blocks for safety factor of each composite. This ensured that the final selection would not break based on our simulated environment. The results from this show that our board has a paddleboardsafety factor of approximately 3.5.
===[ Semester Report]===
The semester report was submitted to the materials department at the end of the first of two semesters this project will run. It summarizes all major decisions during the first section of our project.
===Final Report===
The final report will be submitted at the conclusion of this project.

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