UP Chanter Reed Long-Style Scrape

4th Version 30 June 1996

3rd Version 27 December 1995

Copyright 1995 David C. Daye

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NOTICE: This is an attempt to describe a method of finishing reeds by considering and testing their behavior. In particular it attempts to describe one aspect of performance (the octave ability) that has received little attention in many books and discussions. It is based on experimentation but it is fallible. In particular it is not a method of adjusting finished reeds, although you may be able to find an effective adjustment for some reed after studying this. There may be better ways; your experience or teachers may have better advice!


Where This Applies

This method applies to any of the reeds that use a long-ish scrape which is flat, convex or slightly concave in the vertical direction when viewed from the edges of the reed, when the reeds are finished so that the blades are wider open at the lips (have greater elevation) than desired for playing, and are held more closed by the bridle (collar). Examples include Dave Williams, Kirk Lynch, Mark Hillmann and Paddy Keenan type reeds. Some of the explanation also applies to the small, thin-bladed Tim Britton reeds but most of these goals are attained automatically by his method.

This effort stems from years of my futile attempts at getting the 2nd octave to play reliably, and my finding a lack of information among tutors and reed makers about likely explanations. The fact that it agrees with some common double-reed practices in other branches of music makes me hopeful that there may be some truth and utility in it for the uilleann pipes beyond my own peculiar circumstances.

I have not tried this approach to reeds which use short and/or very concave scrapes (as viewed edge-on) or those that are held open by the bridle against their natural desire to close. I cannot guess at its applicability to those styles until I have tested it.

How the "Long" Scrape Works

Bassoon texts explain that the outer areas of the blade faces affect "higher tones" whereas the centerline area affects "low tones." I feel this applies to the uilleann pipe chanter reed roughly as follows:

Sides, Upper & Middle

As the side regions of the blades are weakened by any combination of scraping, deeper initial gouging, increasing humidity or the use of softer cane, the 2nd octave is attained at a progressively smaller increase in pressure compared to 1st octave pressure. One limiting factor is that this tends to make the back D more likely to "break."

Centerline Vertically

As the vertical centerline area of the scrape is weakened in the same ways, it increases the freedom of vibration and richness of tone in the 1st octave. One limiting factor is that this begins to require a greater increase in pressure to attain the 2nd octave, and to make it harder to maintain once achieved.

Sides, Lower at "V"

As the bottom sides of the scrape around the "V" are deepened or widened, the pitch of the lower 1st-octave notes drops and their freedom increases, reduce gurgling in hard & soft bottom D, sometimes reducing growls or squeals on E, and making the normal bottom D more pressure-sensitive. The latter makes normal bottom D easier to be blown to tune identically with hard bottom D (by slightly underblowing normal bottom D).

Click here for an illustrative diagram.

A Method for Scraping the Reed

Click here for a diagram of the initial scraping process. The goal of this method is to establish the 2nd octave from the very first, with the 1st octave workable but not ideal until the end of the break-in period. I believe this is a rather backwards approach compared to other common methods, but for reasons given below I think it is more likely to produce a long-lasting and well-behaved reed.

  1. Proceed or wait?
  2. Initial flat shallow centerline scrape
  3. Modest side scrapes to lay ground for 2nd octave ability
  4. Rough-finish leaving blades a little thicker than desired
  5. Test to confirm functionality and diagnose.
  6. Additional sanding leaving slight excessive overall strength
  7. Allow to sit & settle 1+ days
  8. Re-test.
  9. Improve 1st octave through break-in and centerline scraping

After the reed is first tied onto the staple I evaluate the elevation or opening at the lips. If the amount of elevation is only 1 to perhaps 3 times the amount desired for playing (or less), the blades have collapsed too much. If they are finished now, they will collapse even more and the reed will not have enough natural tendency to open against the bridle. If the elevation is 2-3 times that desired for playing, the reed should sit for several days to allow stresses to relax, and then it can be finished without collapsing too much.

If the reed is nearly closed before doing any scraping, it should be taken apart. Some cane should be gouged away from the insides of the tails to make room for the staple. At the location of the eye of the staple, the gouge should be no deeper than the wall thickness of the metal. 1/3 of the way down the tails from this the gouge may cut halfway into the tails in extreme cases. This will relieve much of the pressure caused by the staple, and the lips will rest more open after re-tying. The reed should sit for several days for more stress to dissipate before proceeding.

If the elevation is still too near or below my intended final elevation, I may also insert some soft tissue paper between the blades in the upper half and centerline 2/3 (I may need to dissemble the reed to do this). I will put enough material inside to restore an elevation clearly greater than desired for playing. This may cause the edges of the blades to separate; if so I will bind the affected area of the blades with thread to hold the edges together.

If the lips are more open then it's a good idea to start the scraping right away, so that there are some residual stresses available to help the lips close down more. Otherwise the bridle will need to exert too much pressure and the reed will be prone to squeals and other behavior problems.

I advise performing only a modest initial centerline scrape (see step 1 of diagram), then thinning the blades modestly along the sides of the scrape. The reason for thinning the sides early is that this allows centerline cane to begin settling or deforming into its final geometry rather than being entirely carved into that shape. By attempting all the centerline carving at first, that area can easily be over-scraped, potentially ruining the 2nd octave and thus the reed.

This preliminary scrape is finished with medium sandpaper. The ends of the blades are left somewhat thick (always showing flat ends even at the top corners). I stop at this point to evaluate the reed because this is an excellent opportunity to save a high percentage of reeds that might fail due to problems in initial construction.

I affix the bridle to close the blades down to the elevation I prefer for playing. The blades are thicker than I will eventually have them. The reed should play a bit stiff and sharp, yet the 2nd octave should be only a little harder to blow than the 1st octave. The 1st octave will be thin in tone and require a bit more pressure than I prefer. Its lower notes are a bit sharp, and the bottom D (especially hard bottom D) may gurgle. Hard bottom D and bottom-hand staccatto notes reluctant.

I push the normal and hard bottom D's hard to evaluate their pitch, stability and tonal quality. I do the same for back D to evaluate its pitch and stability. Finally I test the 2nd octave by normal jumping from common 1st octave notes and checking the highest notes up to 3rd octave D. If the reed is simply stronger that I prefer (overall) I will do nothing more at this time. But if it is far stronger than I prefer then I need to scrape a little more. Every condition in the next paragraph also assumes that the reed is still too strong to play comfortably.

If the back D is stable I know the reed can tolerate more thinning along the sides of the scrape, which I will do if the 2nd octave takes too big an increase in pressure. If the 1st octave is reluctant and thin in tone, the centerline area can tolerate more thinning especially if the 2nd octave is only a very little harder to blow than the 1st. If the bottom notes of the 1st octave are sharp, and the bottom D's tend to gurgle, then the bottom and sides of the V can tolerate further thinning especially if the reed is rather sharp overall.

I want the reed to finish settling before fine adjustments, relieving stresses that would excessively collapse the reed or make the 2nd octave too hard to play due to over-scraping. Before storing I also evaluate the elevation (amount of opening at the lips) without the bridle (collar). Reeds which require remedial work on their elevation will be left to settle for several days or a week or more. If the climate is dry (humidity less than 70% or so) I may also try to store "remedial reeds" in greater humidity to increase their tendency to reform as I wish.

If the elevation is excessive I will store the reed with the bridle clamping the reed enough that the elevation is only slightly beyond ideal for playing. If it is very excessive I may dissemble the reed and replace the staple with one made from thicker walled metal, but with the ideal inner diameters, to increase pressure on the blades. If the elevation is too near or below my intended final elevation, I will insert some soft tissue paper between the blades to hold them more open, as described above. Care must be taken to avoid nicking or gouging the interior surface of the cane; even soft pieces of scrap cane can do this when jamming tissue between the lips.

Click here for one more look at the method diagram.

As a general rule, the harder the cane, the more extensive the side scraping required for ease of 2nd octave, and centerline scraping (particularly middle and lower areas) for free 1st octave and sufficiently low pitch. The final scrape will be broad and U-shaped. Soft cane usually requires less scraping and the scrape will finish with more of a narrower V shape. The starting thickness of the slip has the same effects as hardness, so a thicker slip will require more side scraping. To a certain extent thickness can counteract softness so a slightly thicker slip made from softer cane will finish much like a thinner slip made from harder cane.

After a settling period, the same tests and finishing steps mentioned above, using gentle scraping and/or finer sandpaper to remove less cane at a time, constitute the fine finishing procedure. An excellent rule at this point is only to do 1/3 to 1/2 of the modification that seems desireable, and then to allow the reed to realign itself during playing and idle time for a day or two before further adjustments. Reedmakers working in climates of great variation humidity should allow the reed to play through the range of different humidities for which it is intended, to see if an adjustment proves sufficient.

Finally, once the reed has become playable, I am ready to apply some sort of stabilization treatment so that the reed will react much more gradually to changes in humidity, and will not collapse in the frequent bouts of high heat and humidity which we encounter here in North America. I have an extended discussion of this process elsewhere.

Briefly explained, I dip the entire finished reed head into Thompson's Wood Sealer, which is a substance designed to render waterproof any unfinished wood used outdoors such as dock planking and house decks. 2 or 3 applications, several days apart, seem to impart quite a bit of stability. This process does not seem to change the pitch or tone of the reed, nor does it leave any discernable coating on the cane. It does not eliminate changes in tuning & tone with humidity, but seems to moderate them greatly.

How Some Other Methods Succeed

"Bridle-early." Some methods call for fixing the bridle and closing the blades partly or entirely before beginning to scrape, or early in the process. This is a way to bend some important centerline cane out of reach of the scraping procedure, but for me it can only be done with rather soft cane. Much of my cane is too hard and stiff to close at this stage.

Some makers use the gouge, upside-down, to make initial scrape, or otherwise advise working the sides of the scrape early in the process. Thus the sides of the scrape are thinned from the outset even if there is no theory offered for what this accomplishes.

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