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Revision as of 20:40, 15 October 2008

Client Comments on Report

We received your report. Your general conclusions could use some clarity. What do you mean "The functions and manufacturing techniques involved in production of the parts themselves."? You mention that there are several signs of good DFMA choices, but what are they? Just the choice of stamping? What do you mean you "came across astonishing numbers" in your DFE? You mention that the gas tank, mower blade, and drive belt have concerns, but what are they, and what are your recommendations?

Detailed comments:

• Good list of stakeholder needs, but you seem to be missing some important ones, such as cost of purchase, cost of use, cleaning, maintenance, and durability
  • Included more stakeholder needs including the ones listed above
  • Discussed the possible clashing of some stakeholders
• Nice description of use. Please also include descriptions of function - how do the mechanisms work? Pictures would be a big help in understanding the mechanism. The assembly drawings are helpful but not sufficient to understand the mechanism without seeing the product. Please expand and explain.
• Why are the front and rear wheels different?
• In your BOM, please clearly identify any subassemblies. You currently have them mixed in with components.
• What prevents the v-belt from falling off the pulley when the drive is released and the belt is slacked? Is the belt constantly in a slip and wear condition?
• Why are you asking us to cross-reference different labels on your assembly drawings with different numbers on your BOM? Please be consistent.
• Nice description of manufacturing processes used, but does the design follow good DFM and DFA guidelines? Can you comment? You seem to focus on user assembly, which is good, but please include your findings about the factory assembly aspects - as you know, assembly processes are quite different at high volume.
  • Indicated processes that demonstrated good DFMA (followed DFMA guidelines)
  • Discussed parts that portrayed findings about the factory assembly aspects
• Your LCA did not examine the use phase, including gasoline combustion or gasoline production and distribution.
• What are your FMEA findings and conclusions?
• Your analysis has a few issues. Your free body diagram does not include all relevant forces (forces in the x and y directions do not sum to zero). Does your tension calculation match observation? Why did you choose this part for analysis? What method did you use to optimize your design? You mentioned that the 0.03 lbs. of saved material could be significant at large volumes - please justify. Are you assuming that scrap from the stamping operation will be sold for recycling? What production volumes are you assuming?

We look forward to seeing your market research and new ideas in the next report.

Client comments on the Mechanical Analysis

This mechanical analysis focuses on a bracket for the engagement of power transmission. It is indeed critical to the operation of the lawnmower machine. Here are few comments to the analysis:

• Please indicate which FEA software you used for the analysis and also provide the material property settings, e.g. tensile strength, Young’s modulus, etc.
• The boundary conditions in the FEA are not well described. Please use textboxes in the picture to indicate your boundary condition settings. Please double check it.