By Guest Author Theo Jager
How These New Saxophone Pads Came About
As a saxophone player and an engineer (in chocolate, chewing gum, cheese, and licorice) I did not like the use of leather in pads. Leather is not a constant material, and has to be replaced every decade. When someone told me twenty years ago that in the tropics the decay of leather pads in saxophones was much faster, I started to look at replacement materials for leather pads.
I tried some of the replacement materials, but then a second problem popped up: For all current artificial pads, it is necessary to have a completely flat tone hole. When you play old saxophones you know that there are cases when it is not possible to make all tone holes perfectly flat. Vintage saxophones most comely either have either bevelled tone holes, or tone holes that have already diminished too much by previous techs.
So the question that bogged me was: How do I pad a tone hole that wasn’t level, with a material that lasted longer than leather?
Of course there was a simple solution for this problem, and it took me only four years to perfect it to a usable DIY technique.
The last prototype (nr. 57) is a round disc made of MDF, which I have made in 38 different sizes (see photo below). These are suitable for octave keys and tone holes, from 14 to 48 mm.
Other sizes can be made as well, so even repadding a copy of the Immensaphone is possible.
As the disks are made of reconditioned wood, you can paint them in every possible colour, as long as the paint is nontoxic.
How to install these disks on a saxophone
- A 1 mm layer of liquid silicone is brought inside the outer rim of the disk with a small stick.
- The silicone layer lays against the outer rim of the disk, and is levelled with the top of the rim.
- Then the disk is put upside down on the tone hole (photo below). The outer rim of the disk may not touch the tone hole, and the disc must be centred on the tone hole.
- The silicone hardens and perfectly fits to the tone hole in that position.
- Be careful not to paint the places where you put the silicone, as the silicone will not stick to the painted areas.
- In the picture, the glue is already put on the back of the disk. It is also possible to put the glue in the key cup.
- When the silicone is hard you can glue the key to the pad.
- The key is easy to position on the pad, as the pad is still affixed on the tone hole by the silicone. This makes it possible to glue this pad in the same height as the pad it replaces, maintaining the tuning of the saxophone, if you thought of marking the exact height.
- When the glue in the key cup is hard, the key can be opened by sticking a small wedge between the pad and the body of the saxophone.The silicone will be drawn from the tone hole as it sticks better to the MDF than to the brass of the tone hole.
- Check with a light if the tone hole is completely closed.
- When not, it is possible to do corrections by adding small amounts of liquid silicone; closing the key; and waiting until the silicone is hard.
- It is also possible to take out the whole silicone ring and put in a new one, when necessary.
What’s new and not, in this saxophone pad idea
There are already silicone pads for flutes and clarinets, but for saxophones they have always been considered to be too sticky. However, what is an entirely new concept, is the forming in place of the pad in the saxophone. Seven years ago already, flute pads have been repaired with silicone in a similar way. They still play without problems.
So it is not a new idea, but how about the sticky part?
After using black coloured silicone, I found that the extra colour added made the silicone soft, and too soft silicone was sticky. Light grey silicone was perfect, as it did not stick, and was not translucent as some white silicones. Translucent is also not good as you want to check the closure of the pads with light.
The takeaway lesson is this: Use light grey silicone, but not too much, because when you put in too much silicone, the pad will be sticky regardless of the type of silicone you use.
In such cases a silicone ring is formed inside the tone hole which grips the tone hole together with the silicone ring on the outer rim of the pad. By removing this inner ring with a needle this type of stickiness will disappear.
As the size of the pad is dependant of the size of the tone hole, it is always smaller than the keycup.
At the moment I fill up this gap with black silicone when it is visible, it looks nice.
And how do these MDF & silicone saxophone pads play?
Well the sound is similar to that of leather pads with plastic reflectors. When you put some silicone on the centre piece of the disc it will give a sound similar to 100% leather pads.
The touch and sound of closing a key are dependant of the thickness of the layer of silicone between MDF and the tone hole.
For people who are tempted to try this at home, I will sell my remaining prototypes on eBay.When I have the eBay number, I will update this article with a link to the auction.
Update
The pads are now on the Dutch eBay site. The auction runs until April 12, 2013.
Hi Theo,
I’m very interested in trying this out myself! I have a couple of questions that I’m hoping you could help me with:
Are you using 4.5mm MDF to start?
How deep is the recession that you route out from the top of the MDF?
If I understand you correctly, you’re putting a 1mm thick ring of silicone just inside the outer lip of your MDF disk. Is the depth of the silicone the full depth of the recession referenced in the previous question?
What is the size of the MDF disk relative to the tone hole? For example, if I have a tone hole where the outer diameter is 20mm, what is the inner diameter of the outer ring of the MDF disk?
Finally, why not make the outer rim of the MDF disk thicker, so that it is the same size as the key cup and thus you do not need to fill the gap with black silicone?
Thanks for coming up with this excellent idea; I’m so excited to give it a try myself!
Hi Maxime,
It is 4.0 mm MDF.
The recession is 1 mm deep and 3 mm wide, completely filled with silicone.
The outer rime is 0.6 – 0.7 mm.
From those figures you can calculate everything.
Be sure to use the most waterproof mdf ( or another suitable material) you can find,
“Finally, why not make the outer rim of the MDF disk thicker, so that it is the same size as the key cup and thus you do not need to fill the gap with black silicone?”
On a saxophone not all keycups are completely concentric with the tone holes.
If you use a thicker outer rim you risk that the tone hole does not fit in the recession.
Some keycups are way larger than their tone holes. For these keycups you need a very thick outer rim. I worked with the idea that a disk on a tone hole should fit in all possible sizes of keycups. Still it happens that a keycup does not allow a 4.0 mm thick disks. In that case I sand the disk on the back until it fits.
I have tried different ways to put the disks on the saxophone. At present I fill the rim of the disk completely with silicone and let it harden. I glue this disk on the tone hole with a minimum amount of silicone, wipe away the surplus and let it harden, Check with a light bulb.
Put the glue in the key cup (at the moment I use glue gun sticks) let it harden.
Put the keycup on the disk. Heat it gently. Press the key cup to the required position, let it harden. Finally tear the disk from the tone hole by pressing on the silicone layer.
Start with one disk to try how it works.
At the moment I am casting disks for my padless saxophone to fill up the key cups.
I will also try to cast some disks wit a recession for a silicone ring, just to see if it is easier to make. This tinkering gives my a lot of pleasure. I hope you will enjoy it too.
Wow, thank you Theo! This is very helpful, and I think I understand you completely. I will be trying this out soon, starting with just one disk as you recommend.
One more question for you: How much of the 3mm wide trough is inside the tonehole, and how much is outside? Is it an even split, so 1.5mm inside and 1.5mm outside? Or something different?
Just subtract half the width of the tone hole and you are correct. In most cases There is a rim of 1 (+/- 0.2) mm of silicone inside the tone hole. If you want a classical sound you could increase the 3 mm slightly.
A small error, it is not the width of the tone hole but the thickness of the brass of the tone hole.
Understood, thank you for your replies. Have you considered putting a top coat on the MDF to make it fully waterproof? Curious how that would affect the sound. Also, are you using a CNC to mill the MDF, or have you come up with an acceptable “DIY” technique?
The problem with a coating is that silicone does not stick to it. Painting the bare surfaces is no problem. I used a laser cutter to mill the mdf.
On the question if it will affect the sound;
This weekend I put three newly made polyester resin disks with silicone in a saxophone for a test. Based on a Canadian thesis, that could not measure the difference in sound of metal and plastic reflectors on leather saxophone pads.
I do not expect to hear a lot of difference in sound between the mdf and resin pads. On the other side I am not sure if this measurement is good enough to distinguish between a Selmer and a Beaugnier.
We will hear, if it affects the sound beyond the correcting capacity of the embouchure I will be surprised.
Update on the resin pads;
The resin pads reflected more high frequencies than expected.
I found it necessary to put a thin layer of silicone on the center of the pads to diminish the reflection. Now the sound is comparable to the MDF pads with a bare center.
Hi Helen,
Time for an update on my pads adventures.
I found out that for most saxophone players the use of silicone and mdf in a saxophone is far beyond there comfort zone.
The only saxophone players who accept it have a technical background.
As a factory engineer using felt and leather pads for a technical solution gives me the creeps.
So I continue my journey and give some highlights in this update.
As sound appreciation of saxophones is subjective this has to be regarded as subjective.
When the saxophone pads show no leaks with a leak light,
there is still room for improvement in an area which I call the micro leak area.
I found that micro leaks do not affect the maximum volume of a sax,
but they do affect the minimum volume and the sound quality range.
When the surface of the silicone seal improves from dull to a metal shine,
which is an indication of seal quality, the dark to sharp sound range increases.
The thickness and shape of the rim of the tone hole also affects this range.
A 1 mm contact rim area between metal and pad sounds better than a 0.6 mm contact area.
Beyond 1 mm I found no improvement.
Above 2 mm (on bevelled tone holes with silicone) you start to get stick problems.
So recently I reduced the contact area with bevelled tone holes to less than 2 mm.
I consider the Martin Committee design of the tone hole rim as the best solution to reduce micro leaks and get the widest dark to sharp sound range.
The next best solution it is the Couturier and early Martin design.
After Holton bought Couturier they deproved this rim in a few years time.
Wich is not a suprise as this is a highly subjective subject.
Just as subjective as the quality of roo pads.
All leather has micro leaks on the sweat pores of animals.
Ass kangaroos have there sweat pores exclusively on their tail,
I accept the fact that roo pads give less micro leaks when no tail leather is used.
I could not find any information on that subject so there is still a change that roo pads have micro leaks.
Also, the padless saxophone is a not recognized improvement of the basic saxophone design.
Combining this with the Martin Committee contact area with a modern silicone type is my ideal solution.
Back to the less controversial subject of mdf and silicone pads.
As silicone is used in most modern leather pads to increase there life,
fellow saxophone playing engineers guessed that the mdf part would give the most problems.
No mdf problems occurred.
It is slightly more difficult to glue a mdf disk with shellac,
but alternative glues have a higher melting point,
so I still work with shellac to minimize the heath treatment of my old saxophones.
Silicone requires a drying time to become stable which is dependent on the thickness.
This process continues days after the silicone becomes solid.
Now I work with silicone layers between 0.6 and 1.2 mm to reduce the drying time.
At the moment I am changing three of the nine remaining leather pads in my Hohner President tenor.
Band members asked my to use this tenor in combination with a plastic Dukoff mouthpiece.
They noticed an improvement in the sound of the band in the three years when the leather pads were slowly changed for mdf/silicones.
But they are still hesitant to use this type of pads.
So I consider it a good invention, but not a commercial one as it is too controversial.
Interesting Theo. Yes, saxophone players are very stuck in their ways. Going outside their comfort zone is not something that they are necessarily interested in doing.
If you lived closer, I would send you my Martin Handcraft tenor and get you to put your mdf/silicone pads in. I would be interested in trying them out. Unfortunately the distance between us makes this rather impractical. 🙁
Like most repair persons, i have for long searched for alternatives for the usual leather pads and therefore found this method of great interest. I find the article not sufficiently lucid to be followed. Just what type of silicone did the inventor use? Was it silicone sealant ? Mention is made that grey silicone is to be used but the illustrations show a reddish sort of material resembling red high temperature silicon gasket sealant. The annular ring appears to be filled up to the top edge of the outer ring whereas the inventor states that the silicone is to be just 1mm think against the outer ring. When the device is placed on the tone hole with the silicon still not set surely it will sink down into the tone hone. How is this controlled? and to what depth should the device enter the tone hole? I much more lucid account is very much in order for others to follow without error. Has such an account been prepared by anyone and if so where may it be accessed?
Hi Vivian,
It is a slow hardening silicone sealant, the same type used for bathrooms.
The red material is the MDF.
When you place a MDF pad with a ring of liquid silicone on a tone ring it does not sink as the viscosity of the liquid silicone is too high and the pad is very light.
It only sinks in when your fingers apply pressure, so it does not fully react as a liquid.
When you use a low viscosity type of silicone it can sink in by weight.
In that case you can apply a ring of silicone. When set apply a second layer of silicone and place it on the tone hole.
The required thickness of the silicone layer is a function of the required feel and noise of the pad and of the elasticity of the hardened silicone, which is a variable.
3 of the 4 types of silicone I have worked with work with a layer of approximately 1 mm. Less, and the pad becomes noisy when closed (0.6 mm), more and the feel of the pad becomes too soft (around 2.2 mm).
The 4th type of silicone was sticky, probable due to the large amount of black coloring in it.
The 1 mm layer gives a touch comparable to leather pads with high density felt.
A 1.8 mm layer feels like normal 4 mm soft leather pads.
When the pads become too thick you can cut some material from the MDF bottom with a knife.
In this way I can repad saxophones that require 3 mm pads.
At the moment there is no foolproof account. That project waits until my eyes are repaired.
I use the MDF pads mainly on my own instruments and I try to change a standard saxophone into a padless (just for fun).
Any news on your project to find a formula for the size and place of the toneholes in a saxophone?
Theo
Thank you Theo,for your detailed reply. I was not able to try out the alternative pad method using silicone as I could not find any machinist to produce the blanks of MDF. A lso the MDF available locally has a very coarse structure and cannot be machined to a thin wall as illustrated in the pictures. The matter of the type of silicone as yet remains unsolved as far as I can understand. I recently made a full set of silicone pads for flute. The first pads I made and fitted after a few days, looked as if they had a greenish card or paper under them. I checked these pads and found that the silicone had corroded very slightly the brass metal cup. This ruled out totally the use of silicone for pads for any instruments which always have brass cups except perhaps some very expensive silver instruments which also have silver cups. I then researched the different types of silicone available locally and finally located a brand of silicone sealant available only in collapsible tubes which silicone was guaranteed to be non corrosive. I successfully made up a complete set of flute pads with the noncorrosive silicone sealant. These pads seat and seal perfectly. Unlike the sax pad method I fitted the pads only after the silicone has totally cured. As the silicone pads are exactly 3mm thick they require a rather light touch to prevent them seating too heavily. A silicone which would be totally noncorosive and would cure to a hardness of around Shore A 35 would be ideal not only for flute pads but also for saxophone and clarinet pads. An alternative material for pads which I have used is that from which pencil erasers are made. These erasers are available everywhere and in different sizes. They may be accurately punched out to whatever diameter is required. The problem with this eraser material is that the erasers are available only in thickness of 5 to 6 mm and cutting them down to the required thickness is not merely difficult but totally impossible for bigger sized pads. About the formula for hole size and position on wind instruments, there is no such. The formulas only give the mathematically correct position and size which have to be finally arrived at by trial and experiment. The moving hole method is the most accurate to arrive at the hole size and position. Returning to pad material , it is totally and ridiculously incredible that no research activity has been carried out to determine the best alternative to the usual and ancient and not long lasting leather and felt method. I am not a scientist, but I have come to the firm conclusion that if there was a method to obtain any degree of softness or hardness using the commonly available nonocorrosive silicone, all pad problems would be totally eliminated and woodwinders would be free of pad problems for the duration of their active professional life.
Hi Vivian, it is a pleasure to read the story of your experiments.
I can recognize a lot of similar experiences. The first one was the corrosion problem. It is caused by acetic acid that is formed during polymerization of the silicone. There is also silicone with added acetic acid to slow the polymerization and make it easier to apply. Acetic acid will oxidize silver in time. When the silicone only touches the rim of the tone hole the acetic acid evaporates fast enough and the metal is not visible oxidized. When applied to the inside of the key cup the acetic acid contacts the metal too long, as I found out in one of my first experiments. I think that the noncorrosive silicone is a type without added acetic acid. I am told that there are only two silicone producing companies in the world with a limited range of viscosity. I still use it as it is one of the most durable materials I could find, also it is practically non toxic. MDF is made in a staggering amount of qualities. It is a pity you can not find a good water resistant type. It is one of the materials that sticks reasonably to silicone. A possible alternative is epoxy, which I use for an experiment to convert a standard saxophone to a padless. The first prototype was successful. After finding a carrier material for the silicone I only used thin layers of silicone, so I am curious how you glued the 3 mm silicone to the key cup?
Cutting of elastic materials to a certain thickness is a nightmare. Modern erasers are made of pvc and styreen rubber. It is to be expected that somewhere on this world someone makes a 3 mm sheet material of pvc, styreen rubber, silicone or polyurethaan. Leaving the lesser problem of cutting small circles out of it.
I agree with your analysis of the formula for holes. I found around fifteen different variables which affect the pitch. A formula with that many variables is unpractical. So that leaves trial and error methods. Finding the right materials for a durable pad is also mostly trial and error. It is possible but there is not much effort by the industry or acceptance by the musicians. Probably they have money to burn.
What are the viable NON-leather replacement pads that I can buy ?
Jim Schmidt offers what he calls “gold pads”:
I have no idea how they perform, but since he also builds whole instruments, I doubt that he would make and use unsatisfactory pads.
Hi Greg,
It is very strange but there are no viable alternatives for the leather pad invented in approximately 1810 by Iwan Müllers.
Then leather was one of the few elastic materials available. Most of the leather applications from that time now use synthetic elastic materials, as leather looses its elasticity in a few years.
Now leather is mainly used in applications where it makes contact with the body and in some musical instruments.
As Jim Schmidt, toptones, resopads, People with Neoprene pads and a lot of Chinese traders have shown it is possible to use other materials for pads.
These alternatives are only viable when the music world will become less conservative.
I think you can find the most viable synthetic saxophone pads on Amazon for $16 a set.
The gold pads are $192 a set.
I have developed the dutch wooden saxophone pads as I did not accept that you have to replace pads every 4-8 years or every year in tropic countries.
And as I like my vintage instruments I also wanted a method of padding which can work without the need to file the tonehole perfectly flat.
For me it works, but it is a DIY adventure which requires some skills and some work.