Straubinger™ Pads are designed specifically for hand-made flutes and consist of different materials and components than a traditional pad. The patented pad support unit and profiled washer are machined to close tolerances, one at a time, on a high precision lathe.

The Design
The pad cup is designed to keep the pad in place so that the pad will come down on the tonehole in precisely the same place each time. Another purpose of the pad cup is to mechanically connect cups to their appropriate companion key or keys.

The stabilizer has a two-fold function. First, it places the pad within four to six thousandths (.004 - .006) of an inch to thecorrect protrusion from the cup. Further alignment is done with full and partial shims. Second, the stabilizer gives the pad a firm and flat base to rest the pad on. This base gives the partial shims a much better foundation than the curved back of a pad cup.The .004 inch thick shimprovides a base upon whichto glue whole or partial shims. These shims make it possible to make one portion of the pad protrude more than another or to increase the protrusion of the total pad. On these .004 inch shims, partial shims or additional shims do not ordinarily exceed .001 inch in thickness. Because of the use of these materials and construction techniques, the Straubinger™ Pad actually becomes more stable with the passage of time. The traditional felt pad, however, becomes more unstable over time and requires frequent adjustments.

The pad support unit provides a rigid base for the cushion and supports the skin so that it does not distort the shape of the cushion. The skin, in conjunction with this support, controls the cushion. That is, it keeps the surface of the skin in alignment with the rim of the tone hole. An important aspect of this unit is that it is sufficiently flexible to allow for correction of any imperfections that come from the tone hole or cup. These adjustments are made by further shimming. The traditional felt pad which does not have this support, warps or becomes distorted from the shrinking skin and unstable felt. The result is leaks and poor adjustments.

The cushion provides support for the skin when the pad is compressed. The type of material used for this cushion is crucial. The problem with felt is that temperature and humidity change the material dimensionally. One might think that it would be easy to find a synthetic material that would not be affected by the weather. However, many materials are not suitable for a cushion because their recovery rate is too slow. That is, when the pad is compressed and released the material must snap back immediately. This is necessary because the next time the pad is compressed it may be with less pressure or a different key combination and therefore the cushion will not be holding the skin to the tone hole. A synthetic cushion is now available with appropriate dimensions, tolerances, and recovery rate.
The purpose of the skin is not only to make the pad seal air but also to keep the cushion in check. Because the skin is supported on the outer edge of the pad by a rim and in the center by an inner collar, the skin will be supported in a flat plane, much as a drum head would work but without the tension of a head.