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Revision as of 11:08, 3 October 2008

Client Comments on Report

We received your report. Your analysis and findings are impressive. Your summary suggests that your most important findings are that the design is already in good shape wrt manufacturing, assembly, and environmental impact, but that it has two important design flaws: (1) difficulty maintaining tune (in general, or during vibrato?) and (2) wear on the pivot points. These seem to be good areas for further study and improvement.

Detailed comments:

• Why does presence of variety in the market have you believe that "any major changes or improvements could be adopted competitively"?
• Good observation that the springs are very difficult to remove or install - but doesn't this contradict your finding that the design is already optimized for DFMA?
• You suggest that professional users would all choose a Floyd Rose over a Fender. Does this imply that the only advantage to the Fender is cost?
• You didn't mention palm muting in your report, but this may be a potential issue with the Floyd Rose bridge, since forces from the wrist on the bridge may detune. Can you comment?
• You never explained why the floating bridge is better at keeping the guitar in tune. Is this only because the Floyd Rose has clamps at each end? Why can't clamps be added to the Fender design?
• In your "product function" section you explain use, rather than how the mechanism functions. However, we see that you explain the mechanism later in your mechanical analysis.
• Part G7 seems to be an assembly with its parts listed later - why is it also listed as a part? Part F9 appears to be an assembly of multiple components. Please comment.
• Good observation that the standardized fasteners simplify manufacturing and reduce costs. You also mention that the large number of fasteners increases assembly time. Are all of the fasteners in the design necessary? Could any of the functions be combined?
• Are DFA guidelines followed with this design? Are all parts inserted from the same direction? Is there potential for ambiguous placement or part mix-up? etc
• What scale are you using for FMEA numbers? You seem to have chosen 1 for "poor detectability", although it seems that it should be 10 to be in line with the RPN concept.
• In your DFE, you suggest that very few guitars are scrapped, but in reality they all are eventually. Please comment. Your LCA analysis is quite good, and we understand that the CO_2 tax will not affect us significantly.
• In your mechanical analysis, you examine a domain up to 12 degrees, where all strings are slack. Do guitarists use this range or any range beyond 6 degrees where some strings are already slack?
• Your force equations seem to list F_pivot twice - should this be separated into x and y components?
• Do you have research that says performers would prefer the tremolo bar to change the frequency of all strings proportionally, or do they prefer to create dissonance? If some users would prefer chords to stay in tune, as you suggest, this could be a very interesting opportunity, indeed.

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

Client comments on the Mechanical Analysis

This is a well-performed and comprehensive mechanical analysis. The assumptions, component information and results are nicely presented. The analysis result indicates that G string has higher nonlinear behavior than others - very interesting.