Cork pads on clarinet

Details

Published on Wednesday, 03 August 2005 20:00

Written by Simon Cole

This is a Selmer series 10S clarinet and a Selmer recital  they are beautiful clarinets in great condition.
 The A in particular does not play as one would expect however, response tuning and tone are poor.
 These are usually very good clarinets. A quick check reveals that the pads do not cover, they are skin pads which have warped over time.

I am going to repad the top joint with cork pads on all keys which are usually in the closed position.
 The other 2 keys will have traditional skin pads.

Cork Pads
Last a very long time
Seal very well
can be noisy for heavy handed players.
Are a lot more work to install as they have to be made and are more difficult to seat.
Work great on the top joint of the clarinet.

Step 1 on this job
All the keys come off. I will make sure that the body itself has no leaks. this includes
 leaks around the octave key and thumb tubes. All the tone holes and vent tubes will be checked and cleaned. the top of each one must be inspected and repaired if need be.

Then I seal the clarinet with tapered rubber stoppers. using the Mag™ machine I measure the air flow though the clarinet body.

Here I am removing the old pad. Instead of holding the key over a flame to soften the glue I use this tool which runs an electrical current through the pad cup. When the Key is back on the clarinet I can adjust the pad without getting a dangerous flame near the body of the clarinet.

 
Now I put one  key at a time back on the clarinet checking the seal of the pad at each step with the Mag™ machine

 I cut the register key pad, but first I check the key itself, I make sure there is no side to side or end to end play and that the key spins smoothly on the rod. If there is any play I will lengthen the metal tube (after making sure posts are not out of align or loose) this is called swaging, there are 3 basic methods I use to do this. If the key does not spin freely on the rod after cleaning them I will straighten the bent key and rod.

I cut the pad put it in the pad cup and check how it falls against the top of the register key vent. The cork pad must have a perfect surface where it contacts the tone hole. If it is not perfect it will leak. Some cork pads are rejected or re cut.

I check the action of the key if all is good I take the key off and file the sides of the pad so they are tapered. You can put the pad on without doing this but tapering the side of the pad will make it less airy sounding. I also check the height of the pad opening. This one is a bit wide ( should be 1.5-2mm) I make a note of it and will check it again when I am play testing the clarinet. All pad heights must be checked. There are general settings I look for but all things being equal I keep them  as low as I can without effecting tone or tuning. My ear is the final testing machine

{mostip}Register key opening will effect the feel and tuning of the clarinet in the upper register. One good trick is to put a small piece of foam under the key. Then you can adjust the opening as needed for any particular note.{/mostip}

Here I am checking the seal after doing 3 pads it's at about .5 
8 on the machine is no seal and 0 is perfect most horns play at 4  and play really great at 2. I aim to keep it under 2. This clarinet started off at 5. The machine doesn't tell you where on the pad it's leaking one still has to use feeler gauges but it does give you a  concrete assessment of your work.
Cork pads have to be cut so they have the same shape as the skin pads they are replacing. Unless there was a problem with the old pads I keep the ones I am installing as similar as possible.

See how the skin pad on the left has a step in it. I will cut the cork pad with a razor blade to make it the same shape. Sometimes you can see cork pads installed where they just stick the cork in without doing this but of course the pad will not cover as big an area and its harder to move the pad around in the pad cup..
This part usually goes OK. I go through a lot of razor blades as they are only good for a few cuts. Every now and then I cut the pad incorrectly *^&%$ and it must be discarded.

This is a better shape, it's also going to make it easier to move it around in the pad cup so I can get a better seal.


This tone hole has a tiny nick in it and the top of the tone hole is pitted. You can re-pad this all you want and if this is not seen to the clarinet will not play at its best. Tone holes can be re-cut as a last resort or the edge can be built up. I prefer the latter as I can keep the original tone hole depth and if the rim of tone hole has a fine edge it seals better than if it has become broader from too much filler or cutting. Filler, I use a number of different materials depending on the situation is applied on the end of a fine needle under a magnifying glass.
This one on the Recital is even worse.


3 parallel cuts across the back of the tone hole. Perhaps from a tool put underneath the pad to change the angle of the pad on the tone hole. This will have to be fixed.

There that's better, those cuts turned out to be quite deep so I built up the cut and then leveled the top. Now it just needs a little finishing

Still lots to do but I hope this gives you an idea of some of the issues and work that goes into padding a clarinet, in this case with cork on the top joint. Skin pads will go on the bottom joints. This is not a how to manual as some steps and procedures have been omitted or simplified..

So next time you drop your clarinet off and ask for cork pads on the top joint while you go out for a coffee you will understand why I look worried.