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At first I experimented with rubber pads. Starting with silicone, then silicone mixed with dry lubricants to alleviate sticking. Next was "Poron" cellular foam rubber with various skins and cushion combinations. The rubbers sealed well but I was told that the tone was dead. So I built the "pad tone tester" to verify this. It turns out that rubbers are springy and so the key/cup can vibrate and dampen out the air column, thus damaging the tone. John Coltman took interest and made some controlled tests that revealed the tone dampening effects of certain cushion materials - read his excellent article "Acoustical Losses in Flute Pads" in "The Journal of Musical Instrument Technology" Issue 23, pages 2 through 6. For a copy contact musictrader@musictrader.com Phone: (425) 413-4343.
I have to give some credit here to Paul Harrington for helping push my pad development in the right direction. He encouraged me to abandon foam rubber materials as unsuitable. Ultrasuede was adopted as a cushion and a thin polymer film was chosen as a replacement for delicate, failure prone bladderskin. The tone improved, but as with many synthetics - stickiness became a problem. In desperation and idle fantasy I envisioned gold plating as the ideal surface of a pad. I then took a wild shot at bonding some specially made Gold leaf to an underlying film. It worked. The stickiness was gone and the tone was wonderful. Many of these pads went into flutes and many are still being used. But they had a limited lifetime due to deterioration of the gold at the tonehole impression. I tried everything but there simply was no way to permanently bond the gold leaf to the film. So I began to impregnate microscopically fine gold powder within the structure of the film so it would be held/captured by the surrounding film yet still be exposed at the surface. For a short time I embedded the gold powder and also covered everything with Gold foil so there would still be gold exposed at the surface when the plated gold wore through at the tonehole impression. I did this because the surface plating was so beautiful. Gold powder does not reflect light the same way as a sheet of Gold and I was concerned about cosmetics. Function eventually ruled over form and the surface layer of plated Gold was abandoned in favor of maximizing the amount of powder within the film. This upgrade occurred in my attempts to make a pad that would satisfy the meticulous standards of Alexa Still and other distinguished players.
Now I had a working pad that helped produce beautiful tone and showed little or no wear. Extensive testing proved the new skin to be several times more durable than bladderskin. This pad found favorable acceptance by those who used them. Some problems occurred because they were improperly installed by techs who did not follow the instructions and treated them as bladderskin pads. The main issue being that too much pressure could be exerted on the skin by the retaining washer, resulting in wrinkles and leakage. So magnetic pad retainers were developed and/or washer spacers were provided to prevent excessive skin pressure. Finally - an inner collar was added to the pad backing so that the washer would not crush the cushion and cause wrinkles. This finally fixed the surface deforming headaches caused by heavy handed installations. The inner collar lies beneath the film so that a perfect seal is obtained. Adding the inner collar was a big step in making the Gold pads technician friendly.
Any pad can stick, so as an added precaution, "magic dust" (a non-toxic dry lubricant - not graphite) is now being added to the film mixture along with the gold powder. This lubricant releases very slowly on a microscopic level throughout the lifetime of the pad. Both the Gold powder and the dry lubricant in the skin are covered by my patents #6344604 and #6940007.
At this point a few techs complained that the pads were a little hard and difficult to install with consistency. Plastic shims were incorporated and the shim stack was minimized. Even so, sealing perfection was achieved by most but not in every case. The pad would form a perfect seal with a little impression forming pressure and it would generally perform wonderfully - but sometimes the film would return/rebound to an imperfect state and lose some of its sealing ability until it was "played in" and took a permanent impression. Extensive R&D revealed the problem to be that the film was too thick and stiff. The solution was simple - I switched to a thinner film and the problem disappeared. Endurance tests were performed again to make sure that the super thin/compliant film was still just as tough and all the leakage tests were repeated several times to confirm that the pad remained stabile. The new skin has proven superior in all respects and offers the best sealing characteristics of anything I have ever tested - natural or synthetic.
An upgrade for the stabilizers was to offer them in high strength anodized aluminum (special order). They are perfectly flat, ridgid, and glue into the cups with much better adhesion than Delrin. Special thanks goes to Karen Claussen for being meticulous in her stabilizer requirements and encouraging me with this improvement.
Finally – I was able to bring another major improvement to the Gold pad my making it “Digital”. The “Digital” Gold pad is my concept of the perfect pad. It is called the “Digital’ pad because it is perfectly flat and stable and it is either completely closed and giving an absolute seal – or it is open. For more details on the Digital Gold pad go to:
And that is where the JS pad stands at present - ready to give reliable service and a pleasant experience to all those who choose them.