According to Rachel, stainless steel springs are much more common because, quite frankly, they are more cost-effective than 10K white gold springs. As we know, precious metals can cost a "pretty penny," and their price changes quite frequently. The material certainly does have an effect on the spring, too. Rachel enjoys working with the 10K springs because she says that it is easier to customize the tension with white gold. The 10K white gold has much more flexibility than stainless steel, which is harder and stiffer. The flexibility of the 10K white gold allows one to really "dial-in" to the exact spring tension they desire. The feel and action on the 10K springs is also something that many flutists will notice. Powell Handmade Custom flutes feature the 10K white gold springs that are all cut to length -- each spring is made for each particular key.
In addition to the wire springs on the flute, there is also a flat spring, which is found on the thumb keys. The thumbs keys are mounted perpendicular to the body, and the mechanism tubing for these keys is very short, so a flat spring is used (a wire spring would be too short). The flat springs are affixed to the key with a very small screw, whereas a wire spring is press fit. Springs are not really an item that would be frequently replaced on a flute. Rachel mentioned that springs, "can eventually get loose, fall out, and then get lost..." but other than that, they are resilient and hold their tension regardless of the material. If a spring should come unhooked from its cradle, that is easy enough to remedy. Also, you have a key that "flops" or, in other words, has no tension, you'll know there is a spring issue at hand!
|Additional view of wire springs, which are press fit.|
|Another view of a flat spring, which is attached with a small screw.|