Fred Gayford - An expert in carbon fiber composites.
"Our goal from the beginning was to design and produce a world class sounding carbon fiber violin no matter the cost or time investment required. It must become an instrument of great beauty, following the classic lines of the master luthiers of the golden age of violin making. Using only the best of the best in materials and investing over four years of research and development, we believe we have finally achieved our goals."
Fred Gayford the driving force behind the Carbon Strad, has more than 36 years of experience working with all manner of composites materials and now specializing mainly in advanced carbon fiber composites. Through his company Gayford Carbon Fiber Composites Inc. Fred supplies a variety of products and services to a number of industries.
Working with composite materials for more than 3 decades has taught Fred that nothing less than the absolute best will do. With the tolerance, flexibility and finesse that molded materials can offer, it truly comes down to the craftsman's ability to shape and imagine the possibilities in creating a product of beauty and refinement. That is why striving for perfection has always been Fred's driving force in every endeavour he takes on.
The difference is in the method
We were faced with many challenges in bringing the Carbon Strad to the marketplace. First we needed to faithfully duplicate the intricate and complex violin shape in carbon fiber. Secondly we needed to acoustically design the carbon fiber violin to produce a world class quality sound . This proved to be very difficult to achieve. After testing 30+ prototypes we finally had what we considered a good sounding instrument. We then had independent professional players evaluate the sound qualities and action of many prototypes. Listening carefully to their comments we continued to make corrections and improvements to the design.
Design and Development:
There a number of methods of producing carbon Fiber parts.
- The first being – “Wet Layup Vacuum Bagging” - a common boat builder’s technique.
- The second being – “Vacuum Bag Infusion” – this is a more sophisticated method used in small airplane production as well as in boat building.
- The third being – “Pre-impregnated AutoClave “ - carbon fiber layup using a heated Autoclave pressure chamber.
This is the same techniques used by the aerospace industry and Formula One race car production. As far as we know, no other carbon fiber violin maker has gone to this method and it was hoped that we could with this advanced technique produce a really outstanding instrument and do our part in taking carbon fiber violins to the next level of sound quality.
A Simple Explanation of our Process
There are 23 separate carbon fiber parts required to produce our violins. After producing the high temperature carbon fiber molds, we were ready to start making parts.
In this method pre-impregnated carbon fiber cloth is placed in the molds and vacuum bagged. The molds are then placed in the Autoclave pressure chamber and put under 60 PSI pressure. The internal heaters then ramps up the chamber to 175+ degrees, after a 12 hour period the heaters and pressure are slowly reduced and the cured parts are demolded. In essence the violin plates are subjected to a clamping pressure of around 8000 lbs at high temperature. Parts made this way have the highest fiber compaction possible with the least amount of excess resin.
We performed many experiments on dozens of violin plates using the three production methods described above. We conducted a tonal ring test on each of the violin plates and the results were very different from each method. Tapping the wet layup & infusion violin plates sounded like tapping on a drinking glass. Tapping on the Autoclaved violin plates sounded like tapping on a crystal glass. This expensive process yielded such incredible acoustical tonal qualities that we decided to use this method for all 23 parts of our violin.
Exhaustive experiments were carried out on many violin plates to determine what the weave direction and layer thicknesses had on the overall tone qualities. Eventually we arrived at the best configuration for our violin tops and the back plates.
About Prepreg Carbon Fiber Fabric
"Prepreg" is the common term for carbon fiber reinforcing fabric, which has been pre-impregnated with epoxy resin including the proper curing agent. The prepreg comes ready to lay into the mold. In order for the laminate to cure, it is necessary to use a combination of high pressure and the high heat of an Autoclave.
Advantages of Prepreg
In a hand layup or vacuum infusion process, it is difficult to achieve a 50% resin content. Typical hand laminates and vacuum infusion, end up with a significant amount of excess resin. Excess resin increases brittleness and reduces the overall properties of the final product. On the other hand, most prepreg fabric contains around 35% resin. This is an ideal fiber to resin ratio. The final result is the strongest, lightest and consistent carbon fiber part possible.
Assembly and Set-up
Our violins are comprised of 23 individual, autoclaved, carbon fiber parts. They are then assembled by hand in precision, mounting fixtures. Dozens of hours of hand work go into the assembly, finishing and assembly of each instrument. Any part of our violins can be replaced if damaged, similar to repairing the parts on a wooden violin. Even though the parts are molded, there is a tremendous amount of hand craftsmanship involved to finish one of these beauties. General maintenance and setup can be performed by any Luthier. Sound post, bridge, strings, pegs etc.