User:Medelen8/ENES100/MakerBot PLA Implement

Goals for implementation performance, cost and quality
The goals for implementation were passed along from the design phase. 1. Tests must be economically feasible. This goal was met, after using many resources from the engineering lab the testing total did not exceed $20.  2. Repeatable results. This goal was met, multiple trials (ranging from 10 to 20) of a single beam were conducted leading to similar results.  3. Accurate test data. This goal was met, all measures were taken to reduce error including many trials and accurate measuring devices. 

Implementation Plan (task allocation and work flow)
For the weeks described:The blocks were rebuilt having little adjustments.   Week 1: The first week of the implement phase was spent researching the filament and figuring out what were going to weigh and how we can test the durability of the weights without using an excessive amount of filament . Week 2: Week two consisted of coming up with a design for the project and how we are able to test the durability of the filament vertically and what size weights we were going to use  Week 3: Week three consisted of us actually building the final design project. And for us to start testing the filament Week 4: many trials were conducted for more testing and building another prototype

Considerations for human user/operators
For our implementation of our final design we did not use a completely stationary object to suspend the filament vertically. Instead we had to use our hands to grip the filament at one end and hold it as still as we could. Naturally this will caused human error because the filament was not held perfectly still every time we did a test.

The manufacturing and/or purchasing of parts
Not applicable 

The assembly of parts into larger constructs


The project used very simple parts two blocks consisting of 2 by 3 inches then another block being 6 by 1 inches. we secured on of the two by 3 inch block to the 6 by one inch block. we secured them together using two nails we placed the block in the middle so it was unable to move and there was the same amount of block space on both side so we can evenly distribute the weight of the objects in order to test the durability of the pla filament if having a certain color really made any changes to the durability of the pla. this was a simple set up that only really required human strength to hold the weight up vertically

Tolerances, variability, key characteristics
Due to human error and other random factors, experimental values were not always similar. To avoid this error multiple test trials were conducted and averages were taken. These average were then compared by means of statistical analysis in order to determine which factors affected PLA' modulus of elasticity and in which way.

The break down of high level components into module designs (including algorithms and data structures)
Not applicable. No high level software was used in the implementation of tests.

Algorithms (data structures, control flow, data flow)
Not applicable. No software used in testing procedures.

The programming language
not applicable

The low-level design (coding)
Not applicable.

The integration of software in electronic hardware (size of processor, communications, etc)
Not applicable. The testing apparatus did not contain electronic devices.

The integration of software with sensor, actuators and mechanical hardware
For our Vertical Filament test we used woodcutter to cut out blocks, and screws to hold the blocks together.

Test and analysis procedures
For all test use this file.

The first test preformed was the 3 point bending test. This procedure was used to determine PLA's modulus of elasticity and to investigate any variable that could affect it. A brief procedure of the 3 point test can be seen below, summarized from the test passed along from the design phase. This brief procedure describing one trial was repeated for the desired amount of trials ranging from 10 to 20. Link to: 3 Point Bending Experiment

3 Point Bending Process (1 Trial):<br \>

1. Pick a variable to test, test multiple beams while only changing the wanted variable. Dimensions depend on desired fill direction.<br \> 2. Place a mark at least 1 cm from each end of the beam and measure the distance between the two marks, this is the Length(L) measurement.<br \> 3. At the center of the beam measure the width(w) and height(h).<br \> 4. Place each outer mark on a support and place the string loop and the center mark.<br \> 5. Mark the baseline of the beam before any deflection.<br \> 6. Add constant increments of mass to the weight hanger while marking each deflection.<br \> 7. Measure the deflections of each weight and preform calculations.<br \><br \>

An example of the data found from this procedure can be seen below. <br \>

Beam Dimensions: L= .12966 m   w= .01004 m   h= .00517 m  <br \>     Beam Color: Blue      <br \>     Fill direction: w x h cross sections<br \>

The second test preform was the 2 point bending test. The procedure seen below was used to determine PLA's ultimate stress. This procedure could be used to evaluate certain variables as well. <br \><br \>

2 Point Bending Process (1 Trial):<br \>

1. Retrieve a used beam from previous tests and drill a small hole at one end.<br \> 2. Clamp the end with no hole tightly to the workshop table.<br \> 3. Tie a coarse string through the hole and place a loop at the end.<br \> 4. Slowly add weight, increasing by increments of 200g.<br \> 5. After each addition of weight measure the new length from the weight to the fixed end.<br \> 6. Continue this process until the beam ultimately breaks.<br \> 7. Record the mass and length at the time of breakage and preform calculations.<br \><br \>

All data found from this process can be seen in the table below<br \><br \>

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To calculate force; Mass(kg) * 9.81 To calculate the σ Ultimate (MPa);

F/A

Statistical Analysis: <br \><br \>To relate the E-values calculated for the 3 point bending tests 2 sample Z-tests were run compare the average E-values while accounting for standard deviation. To run a 2 sample Z-test use either a Ti-83 or Ti-84 calculator.<br \ > 1. Click stat then edit and enter the average E-values for each test. Place each color's values in a different column.<br \> 2. Click stat, right arrow, 1, 2nd stat, and select a list. Hit enter and a list of value will show up. Record the standard deviation value, which is represented by sigma(calculate the standard deviation for each different color of PLA).<br \> 3. Click stat, right arrow twice, 3. On this screen enter in values for sigma 1 and List 1 that correspond to one color (to select a list use 2nd stat). Complete the same process for sigma 2 and List 2 using a different color. Arrow down and make sure Mu1 =/= Mu2, then select calculate.<br \> 4. A list of values shows up. Locate the value represented by P. If the P-value is < .05 it can be concluded that the colors have different E-values. If the P-value is > .05 it can not be concluded that the colors have different E-values because they are too similar.<br \> 5. Repeat this test 15 time to compare all of the colors and another three times to compare the printing methods.<br \>

The verification of performance to system requirements
Not applicable.

The validation of performance to customer needs
By characterizing the strength and stiffness of PLA, future students will be able to make an educated choice when determining which color and direction to print their project parts. By having an easy to access list students will be able to choose the best combination for their desired effect. For example, if they worry about the strength of the part more than its stiffness a group should print the part in neon green, as it is able to endure the highest amount of stress. On the other hand if a group is printing a part in which the bending of a part would produce failure, they should print this part in clear and with the fill direction opposed to the undesired bending, this would produce a part with the largest modulus of elasticity or the stiffest part. <br \><br \>

From greatest to least, the PLA's stiffness dependent on color rate:<br \>

Clear > Luminescent > Blue = Black > Green = Red <br \><br \>

From greatest to least, the PLA's strength dependent on color rate:<br \>

Red > Black = Blue > Green = Gold > Clear > Glow

From greatest to least, the PLA's stiffness dependent on fill direction rate:<br \>

LxW = LxH > WxH

Sourcing, partnering, and supply chains
Not applicable.

Possible implementation process improvements
Throughout the 4 week implement process the group had some difficulties with the 2 point bending procedure. For the next group that does this project make sure that you get all of your printing done by the 3rd week, because one must account for breakdowns and others using the MakerBot. In the future, make it a point to create a makerware file with 5-6 printed at a time to better realize the strength of each beam with more tests for each color. Another thing to be improved upon, but not too much, is the measurement of the beam when it is bent to the point where it is almost going to break. This way one can determine, as before with stiffness, how color and fill direction of PLA affects its strength. While the 3 point bend procedure does require more weight than the 2 point, it is more accurate due to the fact that the length measurement remains constant throughout a single trial of a beam.

We were really hoping to be able to suspend the filament vertically without doing it manually but we were unable to. Because we were using a filament and not a thicker form of the PLA it made it more difficult to do this. The next group that does this project and decides to use filaments instead of rods or beams should try to find a way to suspend a filament vertically for testing so as to reduce human error that happens when suspending the filament manually.

Next Steps
In the future, make sure that all of the set colors to be printed are indeed printed, that way more tests can be completed for more precise results.