How to Use a Saxophone Leak Light

How to use saxophone leak test light for sax repair, what a saxophone leak light is and how to do a saxophone leak light test

A 4 minute read by REVERBLXND

What is a Saxophone Leak Light?

A saxophone leak light is a flourescent tube at the end of a wire that is narrow enough to fit into alto and tenor saxophones, and most of the way through soprano saxophones, and the bell section of baritone saxophones.

It will also work on most bass clarinets if they have leather pads.

What is a Saxophone Leak Light Test?

The concept is simple, light does not shine through leather pads when the pads are sealed. If the light does not shine through, you know the pad is sealing properly. If your bass clarinet has bladder pads, instead of leather pads, the test will not work because the light shines right through them and you cannot tell where the leak is.

How to do a Saxophone Leak Light Test

A saxophone leak light test is a simple tool to use. For alto and tenor saxophones:

  1. Remove the neck of the instrument from the body
  2. Put the saxophone leak light into the body of the instrument
  3. Push down on each of the keys lightly and check if there is any light escaping between the pad and the tone hole. For best results, do this is a dimly lit or dark room.
  4. Where the light escapes tells you where the problem is on the instrument. You have to look at each pad individually making sure the light sits at the right height behind the pad that you're looking at. If you are examining a look on the top pad, for instance, make sure that the light is behind the top pad and then look all the way around for any light leaks.

Note that some of the pads are closing pads — they close by themselves — while others are opening pads. You need to push the opening pads down with your finger before examining them for any leaks.

Common Causes of Saxophone Leaks

There are three common causes of leaks on a saxophone pad:

  1. The pad is cracked or ripped
  2. The pad is not sitting flat on the tone hole
  3. The pad is out of adjustment or misaligned

After a few examinations, you'll have a pretty good idea of how each of these common problems look like.

Typically, on each of these, there will be a little bit of light on the side of the pad when it is closed. Opening the pad should reveal the reason for the leak.

In the first scenario the pad will need to be replaced. Here is a step-by-step DIY recipe for replacing saxophone pads you'll find useful when repairing.

When you find a fairly large leak with the leak light test, and the leak sits on one side so the light is not visible when you turn the pad around, you are likely looking at the second scenario where the pad is not level on the tone hole.

To repair this, the pad will have to be levelled to it sits on the front of the tone hole as well as the back of the tone hole.

If you can see light all the way round the pad, including when you turn the pad around, you are likely looking that third scenario where the pad is misaligned.

This is an adjustment problem.

This often means that one of the connected sets of keys closes before others, whereas they should all be closing at the same time. To fix this problem, you'll likely need to do an adjustment on the back of the saxophone.

You need to check each of the pads individually, and then when you are done with that check them in combination with each other to make sure there are no light leaks.

To check the keys on the bell section, pull out the leak light and insert it into the bell and repeat the same procedure.

Lastly, the leak pipe will not fit into the neck of the saxophone. So for the neck octave key, you just open it up and examine it.