The Designer's Point of View.
Hair accessories function according to a set of basic principles relative to their design. They all depend on the accumulation of hair strands bound together, which in turn creates three basic elements - compression, tension and friction. But as we know, functionality does not necessarily mean friendly - many mass produced accessories do the job but can cause damage in the process.
To better understand the difference between hand crafted items and their mass produced counterparts, let's first look at the individual hair strand. It's tensile strength can be compromised when too much force is applied, as in brushing wet hair where one strand crosses over another in the path of a bristle.
With accessories, damage normally occurs during insertion and removal, as friction and tension overwhelm tensile strength on outer strands, causing them to stretch and break. Stretching is by no means a lesser evil than breakage - a given hair strand does not completely return to it's original shape once distorted, and over time, the number of stretched and broken strands accumulate and undermine your goal for healthy hair.
Individual types of accessories and how they work:
Elastics use radial compression by creating an hourglass shape in a small area. The soft, flexible fabric over latex rubber provides excellent compression with little friction. However, damage normally occurs on removal with these, as they must be drawn over the entire length of hair to remove. Hair friendly elastics such as hosiery bands and those with no metal connector offer a much safer alternative.
Barrettes come in a variety of styles, and use compression in a similar way. The metal band clasp type offers the advantage of removal at it’s compression point, so there’s no linear friction on strand length during removal. Disadvantages are snagging on metal connecting points, sharp edges, and corrosion caused by moisture and chemical action on the plated surface. The stick slide type offers a similar effect by compression, while eliminating these problems altogether. Sizing becomes more of an issue with these, so the thoughtful designer should provide a wide range of sizes as well as an accurate sizing method for the individual.
Sticks and forks use a combination of tension and friction for effective hold – these elements must work in balance with one another. Factors that influence efficiency are weight, bulk or profile, and surface texture. These factors deserve an explanation of their own to understand what makes one accessory superior to another.
Weight is probably the most underestimated factor in design today. For example, a large feather might be thought of as the ideal stick style accessory in terms of it's light weight, thin profile and smooth texture. If the feather weighed as much as a railroad spike, that element would be out of balance with the others and the negative force would cause an obvious failure.
Profile refers to the relationship between the space an accessory occupies and the force it generates on surrounding space in the performance of it's duty. Taken to the extreme, a section of broom handle would be nearly impossible to install because of it's wide profile, even if it weighed nothing and were tapered down to zero. Given that hair strands are anchored to the scalp at one end while the twisted bun coil limits available space between strands, something has to give when an accessory is forced into the remaining space. This wedging or stacking effect is doubled when two sticks overlap one another. Therefore, minimal profile is desired as it offers the greatest amount of functional efficiency for the least amount of occupied space.
Surface texture is often thought of as being ideal when an accessory’s surface is smooth as glass. This can be true, but only when other functional elements are in balance. For example, if overall weight or profile were excessive for a particular design, the advantage of smooth texture would be overwhelmed so the product would fail. A specific degree of frictional force is then designed into the product to keep all functional elements in balance.
Material suitability is also important in a number of ways. As technology advances, we see the most effective results in modern handcrafted goods being done in metals. However, the designer must have a thorough understanding of the characteristics of these materials so that our basic elements are balanced in the finished product. Some materials and fabrication methods in use today focus on aesthetic rather than functional value, and their suitability remains questionable. Not surprisingly, an increasing number of attractive and inexpensive imported accessories regularly appear on the market. These are generally mass produced and often made with plated base metals – the worst offender of all - here's why. Base metals are unacceptably heavy for the strength they offer, often have sharp edges or points, and the plating commonly develops stress cracks over time, creating tiny razor like edges that can shear off hair strands. Avoid these whenever possible. When in doubt, ask the vendor about material composition and quality, and if you don't like the answer.... shop elsewhere.
Lastly, let's talk about sizing.
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