1-D Scale Up Construction

To construct the scaled up box cooker, we followed a manual given to us by Groupo Fenix titled "Solar Box Cooker Construction Manual". The manual includes measurements of the individual parts of the original 30"x30" ovens currently in use in Nicaragua. It also contains a detailed set of instructions for construction. Our team decided to begin with construction of the 1-D scale up box cooker. Using the dimensions given in the manual and our new scale up dimensions, we detailed out the size of each piece for the scaled up oven. Exact measurements can be seen in here.
We followed the process outlined in the manual as close as possible during construction for two main reasons. First, we wanted our new oven to be as similar as possible to an oven that would be constructed in Nicaragua. We were not able to have 100% perfect comparison because some materials available in the United States are not exact matches to materials found in Nicaragua. Despite the small differences in materials, we feel that our oven has been constructed in such a manner that the two are undeniably similar in nature. The differences are small enough that a comparison of the performance of the oven in our laboratory and the performance of an oven constructed in Nicaragua can be made with confidence. Secondly, we hoped to act as an objective source to the clarity and thoroughness of the manual. In the beginning, our group was unfamiliar with the process of constructing a solar oven. As such, we were able to see weaknesses in the explanatory power of the manual and question the construction techniques presented. There were several times during construction in which we were unsure of why a portion was built in a particular way or by a particular process. There are some portions of the manual for which we would suggest considering alternative methods in order to save time and ease the difficulty of construction.
There are two major changes that we would suggest to the construction manual. The first and largest change we would suggest is the addition of an outer layer of fiberboard. This board would be located on the outer portion of the box between the wood and the exterior metal. Adding this layer eases the difficulty of construction by containing the wood curl insulation as you are installing the metal exterior. Although this addition slightly increases the materials needed, and potentially the cost, it provides additional insulation material for the box cooker. We hypothesize that this will improve the cooker's performance slightly, and at worst will provide no improvement. However, further testing would need to be done on the cookers to prove this hypothesis. A second change we suggest is to redesign the rear and center support columns. Theses columns are designed as two rectangular pieces of wood fastened into an L shape. While constructing the oven, we were unsure of why they needed to be done this way. We feel that if the columns were changed to a single rectangular block of wood they would be easier to construct, and they would be able to serve the same structural purpose for the box. The front columns are designed as a single piece already, leading us to believe that it would be logical to convert the design of the rear and center columns to match.
The construction process took longer than we anticipated for several reasons. First, our team members needed to familiarize themselves with the design of the oven, the procedure to build it, and the necessary tools. We underestimated the amount of time it would take for our entire team to learn to use and become comfortable with the necessary tools substantially increasing the time to construct. Second, we did not solicit as much help from the ESW club as we would have hoped. We had only two members come to help with the construction of the oven and these members came to very few construction sessions. We attempted to reach out to members of the organization, but as a team we did not do enough to keep them involved in the project and coming back to continue work. Despite these drawbacks in construction, we were able to complete the 1-D scale up. However, we were not able to construct the 2-D scale up this semester.