• Worldwide DHL shipping
  • High-quality tools for professionals
  • Location Germany
  • Satisfied customers in 52 countries
  • Service: +49 (0) 8074 91 72 42 1
  • Worldwide DHL shipping
  • High-quality tools for professionals
  • Location Germany
  • Satisfied customers in 52 countries
  • Service: +49 (0) 8074 91 72 42 1
How good are Kevlar Tailguts Tailpiece Hanger

How good are Kevlar Tailguts & Tailpiece Hanger?

The extremely durable Kevlar (aramid) tailguts (also known as a tailpiece hanger) have many advantages over alternative tailguts which can be found made from Dyneema/Spectra (high-modulus polyethylene), Nylon (polyamide), titanium or metal.

Metals such as titanium have long been used in violin making as tailguts, however, recent innovations in materials science, have produced a number of high-performance synthetic alternatives.

Kevlar, developed by DuPont in 1965, is a para-aramid fibre which has liquid-crystalline behaviour, and mechanical drawing of the fibre orients the polymer chains in the fibre direction. Dyneema (commercialised as Spectra in the US) has been available since the late 1970’s, and is a high modulus polyethylene which is modified on a molecular basis and additionally stretched in one direction.

Kevlar and Dyneema are very often wrongly confused (with Dyneema tailguts assumed to be Kevlar) and while they do have a few similarities, Kevlar has a number of preferred properties which are specifically beneficial for the use as a tailgut.

Properties of Kevlar ropes

Kevlar and Dyneema/Spectra ropes are light and withstand high tensile forces, however, they differ significantly in their elongation at break, and creep properties which directly impact the suitability of their use as a tailgut.

Elongation at break is the change in length of a material compared to its original length at the point of failure under a specific load, it is usually expressed as a percent (%). This is important for tailguts as it provides tension and stability in the tailpiece and therefore the strings.

Creep is material property that is frequently misunderstood, and the impact under-considered for specific applications. Creep can be defined as the continued extension of a material when subjected to persistent, long-term, static loading and can occur at forces well below the yield strength of the material. This is a very important property to consider in violin making as high creep in the tailgut continually changes the setup of the instrument in a negative way over time. The distance between the bridge and the tailpiece and so the string distance constantly changes thus continually altering the sound.

It is widely known in other areas of application (e.g. rope/climbing, sailing etc) that Dyneema/Spectra exhibit high creep when exposed to tensile load for extended periods, likewise Nylon and metals will also stretch under prolonged tensile forces over time. This, of course has a negative effect on the tailguts performance and strength, resulting in tension reduction thus impacting vibrations, sound, and the play of the instrument.

Kevlar doesn’t stretch under string tension, or creep over time resulting in ultimate stability in use.

Two different types of Kevlar tailgut

There are currently two types of Kevlar tailguts available on the market. Kevlar is naturally a recognisable pale-yellow colour, although due to recent innovations in colouration technology, since around 2013 it can be found in other colours. Information link

The Kevlar tailguts utilise different construction approaches, one which is braided, the other which is a braided Kevlar core with a Polyester sheath. Since Dyneema looks very similar to the braided tailgut (without sheath) it is very often wrongly sold as Kevlar tailgut.

For tailguts made of Kevlar a protective sheath is particularly important because Kevlar is sensitive to UV and so the sheath provides extra protection. Information link For tailguts made of Dyneema a sheath is also important as creep is exacerbated by light. As such, caution should always be taken with un-sheathed tailguts due to long term light exposure.

Furthermore, in terms of design and elegance, a sheathed tailgut has a classic appearance and blends discreetly into the overall ensemble of the violin or cello.

High quality sheathed tailguts are stable in diameter, and provide a clean silhouette, even while under high tensile load around the saddle.

What is the perfect knot for tailpiece cords?

For an especially safe and beautiful knot, we recommend a figure 8 bend (double figure 8) or a water knot. For the sake of simplicity, a fisherman’s knot can be placed. Especially when adjusting the length this type of knot is easier to handle.

To prevent fraying, it is recommended to seal the cut ends, ideally by gluing with a low viscosity superglue, or alternatively, sealing with heat.

It is again generally known in other applications, that due to the low friction properties and slippery nature of Dyneema, that it is very difficult to knot, and that knots tend to slip, or wander, and not hold in place. Information link

Kevlar tailguts for the perfect sound

Due to its vibration properties and the way sheathed Kevlar transmits vibrations, many players feel that it tends to make an instrument sound richer and more refined, potentially quickening the instrument’s response, tightening its feel under the bow, and increasing its intensity. Many players feel that it tends to make an instrument sound more open and fuller, and many of the players notice more volume.

“My instrument really sounds much better. Grain, precision, projection, depth, personality, centred and direct sound”.

Kevlar Tailgut & Tailpiece Hanger

© by Mag. (FH) Benjamin Schilbach & Dr. Katy Stevens PhD

Published in: BVMA Quarterly, Issue 107, Sept. 2022, Magazine of the British Violin Makers Association BVMA