The objective of this project is to improve and decrease the negative impacts that 12 string guitars obtain from high string tension, temperature, and humidity.
Sponsored by: The Learning Factory
Team Members
Daniela Rubio Perez Charles Raysik Kassidy Bear Derek Klass
Instructor(s): Jason Moore
Project Poster
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Project Video
Project Summary
Overview
The introduction of the innovation of the 12 – string guitar became demanded by many rock bands around the world. As it allows for a distinctive style that many songs would not sound the same without it such as Hotel California by The Eagles. The main problem with the current 12- string guitar includes changes in temperature and humidity negatively impacting the guitar in a variety of ways. Such as, warping, bridge lifting, belly bulging, and more which all impact the guitar’s playability. Another problem is the high string tension from the 6 extra strings on the guitar, forcing users to tune their guitar lower than the original E standard.
Objectives
– Building a guitar with materials that can withstand different temperatures and humidity yet still utilize traditional materials.
– The design of the guitar must be able to resist the high string tension.
– The guitar must be easily tuned to a traditional E – Standard.
– Implement an adjustable truss rod allowing for easy maintenance in the future
– Uphold the integrity of an acoustic guitar and keep the same pitch, volume, and resonance as an original 12- string.
Approach
– Met with sponsor to determine the project needs and scope.
– Assessed functionality and shortcomings of current guitar design.
– Purchased 12- string guitar to modify.
– Conducted baseline testing (temperature, humidity, and string type) on unmodified guitar.
– Created modifications to streamline tuning and prevent large changes in tune.
– Integrated all changes to the guitar.
– Conducted the same initial tests on modified guitar to determine change in resistance.
– Created documentation of design changes, testing methods, and future considerations.
Outcomes
– The Final design included locking tuners, different strings, adjustable truss rod, and a bridge cover
– The tuners have a mechanism that locks the string in place at the tuning post, providing more stability and reducing the chances of the guitar going out of tune.
– Elixer 80/20 bronze strings were the least likely to go out of tune through various rotations of the tuners. Also, the string types with the lowest tension, ultimately reducing the tension of the strings on the guitar.
– The team attached a gear to the truss rod, allowing the player to adjust the truss rod if there are any changes to the neck of the guitar. The addition of the gear would allow the need to not remove the strings.
– To combat the bridge warping, a case will be designed around the bridge, making it harder for humidity and temperature to reach the bridge.
– From temperature testing the E strings were the most susceptible to temperature changes, however through the various modifications the strings were able to stay in tune through a longer period.
– From humidity testing similar to the temperature tests, the E strings were the most susceptible to humidity, however the implementation allowed for the guitar to stay in tune through various humidity changes.