Grading Reed Cane

Latest update with photographs 3 December 1996
Previous update 23 August 1996

Copyright 1996 David C. Daye

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The Problem

Reedmakers realize that cane is not a uniform or consistent substance. For ideal reeds, the construction (initial thickness, amount of fine scraping or sanding, perhaps other dimensions) must be varied to suit a particular piece of cane. One of the most basic and important properties of cane is its stiffness, which determines how it will respond to shaping, how it will vibrate and therefore how the reed must be finished and fine-tuned.

Until recently it has been difficult if not impossible to give a learner any of the wisdom of an experienced reedmaker in evaluating cane, except to hope that a supplier would sell only appropriate cane. Stiffness cannot be evaluated until a reed is partially finished. A related property, which is a good predictor of stiffness, is hardness, which can be evaluated in advance by scoring the bark with a fingernail. Early in double reed manufacture hardness can be evaluated by noting the ease or difficulty of chiseling and sanding. But these measures have traditionally been learned by feel and are not easily discussed or compared orally or in print.

A classical wind player (credit below*) some years ago, has developed a fine predictor which has recently come to my attention through an online forum. Orchestral woodwind reeds are made, adjusted and played soaking wet. While preparing cane, this player noticed that different pieces of cane have different densities, and float higher or lower in water upon initial immersion. He learned that the density relates well to hardness and stiffness. Out of his observation comes an accurate and reliable test for determining--before starting the reed--the properties and suitability of a piece of cane, and for describing cane accurately to others. In fact at least one oboe reed supplier uses the test to offer 12 different grades of cane for sale.

The Test

Seal the pores at one end of a tube of cane with bees' wax. (Click here for 36 KB photograph). If the end nearest a node can be identified, it should be the end waxed. Immerse that end in a tall container of water. Guide it by hand, carefully maintaining upright or lengthwise immersion, until the cane floats at its natural level. Mark the waterline, remove the cane immediately and dry it.

Measure the overall length of the tube and the length which was immersed, and compute the percentage immersed or sunk. This "sink percentage" is a number which relates well to the hardness or stiffness of the cane.

For pipes whose reeds are made dry, such as uilleann pipes, the cane should be left to dry for at least a day before proceeding to make a reed.

Click here for 50 KB photograph.

Quick Measuring Jig

Click here for a 55 kb photograph. After cane is dunked & marked, this jig shows the sink-percentage on any length piece without the need to measure and calculate.

Accuracy Note

Cane varies in hardness noticeably from one side of any tube to another. A test of whole tubes is useful for pre-sorting, but accurate knowlege requires a test of each individual strip split from a tube. After splitting, plane the edges of the strip to a uniform width. The slip does not need to be perfectly straight but it must be a consistent width so that one end is not heavier than the other. Then test and mark the cane to identify its sink percentage for future use.

You will need to use this test for a while and keep some notes in order to learn to identify cane that is ideal for your reeds. My preliminary judgement for my rather standard size chanter blades (1' to 1-1/8" long exposed head, 1/2" wide blades), for use in my variable Ohio climate, is as follows:

  • Soft cane -- 48% - 53%
  • Medium cane -- 54% - 59%
  • Hard cane -- 59% - 70%
  • My preliminary experience suggests that much below 50% and cane is too soft, above 70% and it is too hard. I expect that different ranges may be considered normal in very humid or very dry climates. There may also be variation according to the "recipe" used; larger and wider blades will tolerate harder cane than smaller or narrower ones for example.

    *Credit

    An email discussion credited Lewis Hugh Cooper's article "Reed Making Notes: Selection of Gouged Cane", IDRS Journal No.19, July 1991, pg. 45. IDRS is, I believe, the International Double Reed Society. I have not checked the article myself.

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