Updated 20 October 1997
Updated 14 Oct 1997
Updated Sept 1997
Created August 1997
At 09:55 PM 8/18/97 -0600, Eric C. Olson wrote:
>I recently acquired all the makings for a P.C. and hope to start gluing
it
>all up, perhaps this weekend. But first, some questions.
>
>1. Generally speaking, is it not true that the key function of the
tubing
>is to create the contour of the conical bore?
Exactly.
>Are you also trying to model the chanter wall thickness that affect
the hole
>geometry??
Well I'm certainly trying to achieve enough wall thickness to ensure that
the
beast acts like an uilleann pipe chanter. Hence the rubber heat-shrink
on the
early prototypes and the CPVC plastic pipe exterior on the current models.
>2. Is the 3/8" plastic tubing that fits into the top of the CPVC
used to
>provide structural mass between the PVC and the chanter throat?
Well to save wgt the thick brass section stops at back D. The top of the
chanter is then a thin stem which would rattle around loose inside the
CPVC
pipe. So I put a short length of intermediate size plastic tube in there
to grip the brass stem (inside of which lies the throat) and the outer
CPVC tube.
From: David Daye <ddaye@postbox.acs.ohio-state.edu>
Subject: Exploring / Diagnosing Bores X-Sender:
As Ken McLeod indicates in his current _An Piobaire_ article, it is often important for the maker to adjust the bore of a chanter in addition to adjusting holes etc.
But how to know where to adjust?
[ I'm not recommending here cutting into chanters that other people have made; though if a spot for a helpful rush can be found, there might be some temporary relief while negotiating with the maker. ]
Craig Fischer has said that a favorite trick of his for diagnosing bores is to make up a modest length of some rushlike object, perhaps a thick strip of cane etc., put it onto the end of fine wire, feed this up from the bottom of the chanter and then nudge it into different positions along the bore & test.
Any and all notes & effects are fair game: fingered notes, hard bottom D, stability of 2nd octave, etc. Under the rules, any of these are also eligible to be upset as a side effect of the 'improvement' you seek to make.
You have to make an important reduction in the volume in that region over a significant length. My seat-of-pants intuition would suggest something longer than a typical step between finger holes; perhaps a bit shorter in the upper bore above the thumb. Diameter would probably be less up there as well. Perhaps a length of 1/4 or 1/2 round thin brass tube just a little less o.d. than the min. bore i.d. in any zone might also work. In any case, the test rush must be large enough to have an effect and small enough not to render the chanter unplayable.
Fish around throughout the chanter to find as many spots that affect the particular problem(s) you are struggling with. I'd guess that there must almost always be at least 2 "hot spots" per note, naturally having different side effects, and probably affecting the 2 octaves of each note differently.
If the rush improves things, you might elect to live with a rush there or in future models leave a tiny amount of extra wood in that zone. If the rush worsens the problem, the chanter can be opened up carefully with a shortish tuning reamer in that region.
Brass bores can't be reamed to open; save the information for the next specimen. They can be 'rushed' however with a 2-5 mm short cylinder of tubing pushed into place to extend the desired existing tube end, or a longer half- round or taper-cut tube segment that can be wedged in for testing and spot glued if it proves helpful.
For experimenting with penny bores it might be useful to cut each tube bottom some 5 mm high and then "unream" the chanter by adding tube bits back on, working backwards from the traditional wood chanter approach.
david
Eric Olson writes,
>3. Regarding the overall construction:
>
>How critical are the dimensions? My guess (and level of technical
>competence) is that a millimeter give or take is not the end of the
world.
Consider it the end of the world on hole position. You should take
great care with them. I'll allow *half* a millimeter either way.
With bore tubes, probably 1 mm is ok on any 1 tube, but if you
have 2-3 tubes all long or short by that much, you've made an
important change to a region of bore. At least as much as adding
or removing a thick rush over the distance of 1 more tube that
was changed.
All that I did from May to July's Irish Week 'premier' with the
CPVC covered chanter was to vary 2 tubes between back D and A
by either 1 or 2 mm. There's a story for a few pub pints some
night.
>I am a little concerned, that there may be more impact where the diameter
>change occurs right where a hole is to be drilled. Any comments?
I don't think this is really a problem but I could be wrong. The
only real 'impact' I've had in this design is dropping 2nd octave
A. This is a generic Rowsome problem however, certainly in the
Quinns and (some) Lynches, so I tend to dismiss the idea that the
tube end (which is at or near the A hole) is really what's wrong.
>4. Regarding hole placement versus wall thickness (number of concentric
>tubes at that location)?
>
>Eb=5 =>
>15/32 - 1/2 - 17/32 -9/16 - 19/32 - 5/8
Yikes! I've got to print this out and study it.
If you're building from the _Pipers' Review_ plans I've since built
2 chanters from the article, reading from it in the shop, so I know
it's right. (I'm just waiting to see what God does to me for saying
that!)
>Fitting the 3/8 tubing to the top of the PVC was a bit tedious as I
don't
>have anything but the most rudimentary of tools. Any tips here for
the next
>time.
You can sand down the outside of the inner tube. It's only present
for compression structure, it's outside of the music system entirely.
If you get too thin set it in place with epoxy slopped around it,
it's silent and invisible so no matter.
Good luck!
"YMMV"
david daye
>Regarding assembly, do you
> a) glue up the copper,
Well brass. Yes.
> b) insert the copper into the CPVC,
No. First I put the 2 plastics together. The outer tube is actually a bit
snug
so I open it up a bit with a large drill, or else sand down the outer part
of
the smaller plastic tube. I set it in 1/8" or so, coat the outer (of
the small
tube) with super glue, then quick hammer it in. Wherever it stops, there
you
are, it's not very critical, and the end can be cut / sanded once the whole
assembly is together. The brass inner bits are what define the music.
>4. Have you considered sculpting the CPVC at the holes to allow for
easier
>finger placement? Would this be inconsistent with your design?
Yep. It isn't necessary ( I'm pretty sure ) but before long there will
be
lots of other people building these and the consensus may differ. I couldn't
do a sculpting job that would look very good, personally. And a little
birdie
tells me that varying the diam of the hole slightly makes as much difference
as sculpting rather a lot.
>5. Regarding the undercutting of the holes, I presume you take a
>hole-by-hole approach here.
Very little is needed so I'd be inclined to play it for quite a while first.
I'd undercut upwards to sharpen the 1st octave note more than the 2nd,
downwards for the reverse. I do this by inserting a bit or a dremel tool
and grinding away for a while. Do 1/4 the amount you think you might need,
then live with it for a while.
>If so, do you start at the top or the bottom?
I start with the worst note.
>Does the order matter?
I think a knowledgeable pipemaker would say it does. These p-c's have been
so close
that the undercutting is so minimal that I don't think it matters in this
case.
>6. Don't worry, this is just the beginning. When I get started, I'll
have
>plenty more questions.
2 things I recommend not previously published (I've said them here). Flare
the
bottoms of each tube (other than the 2 that end at the bell) so as to make
a
fairly snug seal against each outer tube when it goes in. This makes the
chanter
noticeably louder and gives it a fuller, warmer tone in the 1st octave.
If that's
what you want. For an indoor practice chanter, don't flare, and limit your
gluing
to the upper inch of the tube joints (but glue thoroughly).
Also, make the back D the next size smaller. I allowed too much sharpness
for
humidity, not realizing that wood bore changes were causing some of the
change
I'd been allowing for. Make the hole 1/64" smaller than recommended
(you can
open it up later if it seems flat).
Enjoy!!
Eric Olson writes,
>Making some progress on the PC construction, but a few questions still
linger.
>
>1) Regarding the flaring of the 9/32 (100mm) section:
>
> I presume not much flaring is needed (or indeed possible) since it
has to
>fit
Yes. I advise flaring *every* interior tube (other than the one that
ends at the bell, and maybe that one too, the 17/32" I.D. tube) to
make the chanter bore thoroughly airtight and therefore louder
and brighter in tone -- so long as this is what you want. The
P-C will never be as loud and bright as the strong Quinn and
Rowsome so unless you're purpose-building an "apartment" practice
chanter you should flare.
Actually as I think about it, the 2 innermost pieces, the 'Throat
Tube' and the 'Upper Bore Tube' which have the long taper tails,
there's no bottom end available to flare, so a thin layer of
teflon tape round the cylinder portion (or the lower part of this)
and/or a thick allowance of glue will help.
Yes, just enough to seal, the tube must still slide easily enough
that it won't freeze in the wrong position when the superglue is
quickly setting.
>How do you create the flare and what is its purpose?
If you're using a common hardware-store general purpose tapered
reamer, just twist it backwards and force it into the tubing.
Just a little, check the fit, repeat etc. till you get the idea
how much pressure is needed. Or use closed needlenosed pliers;
or most anything long and narrow that fits inside the tube and
can be twisted and forced inwards.
If you flare too much and the tube won't enter at all, or requires
too much effort to slide into place, you can hold the tube flat
on a metal file and spin by hand a few or a dozen turns, eroding
the outside surface of the flare enough to get a tight but slidable
fit.
>2. Regarding the two tuning inserts with the ground-down sides:
>Seems like you can't glue them in until you have the right contour
and
>position. Or do they ever get glued in?
Your choice. I made the Belfast Chanter this way and slopped a lot
of glue into it just in case it might have ended up in unforseen
circumstances, crashing into railway station floors or bodhran
player's foreheads etc.
You can also make the cylinder parts much longer so that they
stick out the head of the chanter maybe 5 mm, eliminating the
need for any 'reed seat' tubes, as I've done with the
larger of these 2 tubes on some models I'm using for
testing; then if you just work some teflon tape low down
onto it just above the top of the tapered tail, the assembly
will hold position for you while playing but you can grab it
for fine tuning against different reeds or to experiment if
you have problems with ICN (Impolite Chanter Noises), dropping
octave, reluctant hard D or other issues. Also handy for helping
make the whole assembly more accomodating to air changes
when pubbing or doing outdoor festivals etc.
>3. When drilling, do you recommend starting a small pilot hole,
then
>gradually work up to the prescribed diameter?
Not gradually. I didn't have this part down very thoroughly in the Review
article. I now center-punch (lightly) all the hole positions, then pilot
them
with a very small diam drill. Then I go for the intended hole diams. The
bits
I'm using have tiny pilots on them; I'm no expert on this subject but I
thought
it would help them track.
Push *slowly* and I think you want the drill spinning rather fast, especially
near the end, or it will peel all the layers of brass apart into an intriguing-
looking weapon. Use plenty of oil when drilling the plastic areas or the
bit
will heat up and melt the hole too big. I use almond oil, the bore oil
stuff;
any lubricant will do the job, even the correct lubricant.
From: David Daye <ddaye@postbox.acs.ohio-state.edu>
Subject: Make No-Solder Twist-Keys
Keys for penny or (temp replacements for) traditional chanters and all homemade regulator keys. Cost, nearly 0 if homemade; labor, maybe 15 minutes depending on aesthetics; tools, saw, 2 pliers and 1 drill. No soldering.
Illustration, to be linked to penny chanter pages soon, is at: makepipe/twistkey.gif
Use medium thickness brass strip 1/4" wide; 1/16" thick perhaps.
Cut length of key. Leave enough for finger at end, flat. Make a 90 degree twist over short distance, from there through the location of the axis. Make another 90 degree twist for the pad end of the key.
File or grind as desired for aesthetics.
Bend pad-end down a few degrees at the twist, then back up parallel so that pad can contact the chanter hole squarely. Fix leather pad on underside of end with (super)glue.
Grind underside rear of vertical center axis section so that the finger end is clear to pivot downward.
Drill hole through mount for pin, use rubber o-ring or Keenan style rubber band as spring. ;)
david daye
From: Terry McGee <terry.mcgee@netinfo.com.au>
Subject: Re: Make No-Solder Twist-Keys
Two minor comments on David's instructions for home made keys:
David mentioned filing or grinding the brass keys. Grinding brass (or other soft metals like aluminium) is generally regarded an unsafe practice. It can clog the grinding wheel which in extreme cases has been known to make the wheel explode with nasty consequences (especially if a big wheel running at a high speed). Much better to file soft metals.
If you do need to remove a lot of metal quickly, consider a sanding disk or drum. A course paper spinning at a good speed will cut brass away very quickly. Hold the key blank in pliers or at least wear leather gardening gloves. The key will try to tear out of your hand, and it will also get too hot to touch suprisingly quickly.
The second comment relates to holding the pad on to the key. The time-honoured way to secure pads to keys is wax, and, as so often is the case, the time-honoured way has some real benefits. It's quick, cheap, neat, easily removable, and self-seating.
There are a number of different approaches, but here's one:
Cut your leather "pad" to suit the pad area of the key with a bit of overhang all round. Heat the key plate with a small flame. I use a little alcohol lamp I made from a jam jar with a bit of brass tubing through the top to hold a cloth wick. Terrible waste of alcohol! It works great, but for the occasional user, a cigarette lighter will be fine. Gotta find some use for products from the tobacco industry, since (I hope) they're about to fall on hard times!
Melt a bit of wax onto the warmed plate and touch the plate onto the back of the "pad" (the rough side). There are special waxes used by instrument makers and repairers, but I imagine any wax will work - the load is not very great! Don't press hard - you don't want to squeeze the wax out yet. The wax will cool and harden quickly, then you can trim the leather down to the edge of the key-plate. I use a scalpel for this - they cut skin so well you'd think they were designed for it! Mind your fingers, you will need them later to play the instrument.
Now mount your key onto the instrument. It probably won't seat very well. Warm the back of the key plate with your little flame (being careful not to singe your instrument) and you should be with by the sight of the key settling down against the pad seat. Resist the temptation to press hard - that will make the pad seat only when the same pressure is applied. Rather, let the spring provide its natural pressure.
If any wax squeezes right out, resist the temptation to wipe it off (especially with your finger - it's quite hot!). Rather, let it cool down. It goes crumbly at room temperature and can be peeled or cut away easily.
As you seat each pad, test for airtightness by sucking lightly on one end of the instrument, with all the other holes covered and a bung in the other end. You should not be able to detect any leakage.
Here's another of the "tricks of the old masters". To help locate where a pad is leaking, make a feeler gauge from a thin strip of cellophane, taken from the "cello-wrap" around a new CD cover. (This makes a digital feeler gauge. If you prefer the more traditional analog feeler gauge, use cello-wrap from a cassette!). Tape one end of the strip onto the end of a convenient probe - a pencil will do.
To locate the problem area in a pad, open the key and let it close on the free end of the feeler gauge. Withdraw the feeler gauge, making a mental note of the amount of drag needed to pull it free. Open the key, move around to a new place, close the key on the feeler and pull again.
The amount of drag should be equal all around the pad. If you find a leak, you can remelt the wax to reseat the pad, relocating it if necessary with a spatula. A convenient tool here is the back end of a metal nailfile.
I don't know how well these time-honoured methods will work on David's interesting key system, but possibly worth a try.
From: Casey Burns <cburns@kendaco.telebyte.com>
To: uilleann@lists.acs.ohio-state.edu
Subject: key making
Here's how I make keys for bagpipes and flutes - I use silver, but it would work for brass if one's torch is hot enough.
Tools needed: Torch (hardware store torches work fine) 2-3 fire bricks hammer some surface to use as an anvil, such as a pice of 1" plate solder and flux - plumbing solder is fine
I start with a strip of silver (available at a Jeweler's supply, such as Rio Grande) 1/8" in cross section or larger, square profile, about 1" longer than the key. I make a little "kiln" by breaking one of the fire bricks into 2 pieces, and setting them on the other brick to form a "slot" about 1/2" wide (to focus the heat). I set the strip of silver, which I have straightened in the slot so that the end is flush with the edge of the brick.
Then I apply heat with the torch to that end. With the focusing of the heat, the end starts to melt, literally. By "brushing" with the flame, you can create a little "bubble" of metal that will travel up the shank, growing slightly as it travels. Once the bubble is about 1/4" in diameter, let it cool.
A number of hammer blows will spread the bubble until you have a nice 19th century style touch on the shank of a key. The shape can be further refined by filing and polishing with sand papers. The rest of the shank can also be hardened by a bit of hammering as well.
The pad can be made from 16 gauge silver, cut to a square or round, and silver soldered to the shank. For the actual pad, I use garage door insulation (self adhesive) cut to 1/16" thickness with a razor blade, or kayak flotation foam.
I usually drill the holes for the pivot before the pad is soldered on. I also drill a hole and solder a piece of 1/16" round silver (annealed) under the touch for a flat spring made of hammered silicon bronze.
I'll be making keywork in the next month and putting photos of the process up on my website at http://kendaco.telebyte.com/cburns
Casey Burns
From: "Joel Shimberg" <shimberg@hotmail.com>
Subject: Re: Make No-Solder Twist-Keys
Date: Sat, 11 Oct 1997 07:41:02 PDT
My flat set has sheet-metal keys. The hole-cover is soldered on, but the rest is one piece of sheet brass. The shaft of the key is folded in half lengthwise, with the fold uppermost. The touch is shaped like a narrow rectangle with a rounded end (away from The keys are comfortable and strong enough to have lasted a century or so.
Date: Mon, 20 Oct 1997
From: David Daye <ddaye@postbox.acs.ohio-state.edu>
Subject: Reed Trick for Penny-Chanter
Brief tech note here for Penny-Chanters, and a general speculation at the end.
Phil Sexton had asked one time if I carved chambers inside the Penny-Chanter reeds. I said more or less no, but the real answer is closer to 'yes.'
My test reeds were all made with Rigotti French bassoon cane, which usually does not deform after binding as much as Spanish cane (in my experience). But I'd forgotten that those blades were all retied after having spent their first months on unusually thick (.025") copper staples. Therefore they had taken a rather roundish cross section in the region above the staple that I more often get in Spanish cane reeds on thinner staples.
This translates to a more open "chamber." Anyone making Penny-Chanter reeds and finding the 1st octave chronically sharp, especially G and A, and perhaps having a bit of flat back D, might get truer tuning by using a smaller diam sanding cylinder or perhaps a gouge carefully, to gradually open up the bottom 1/2 of the reed and tails perhaps .01 " or so at the deepest point around the eye, beginning gently just above the bottom of the V and quickly spreading out to the edges.
This may not necessarily rescue a finished reed, especially if there is not much cane to spare, but it may help with new ones if done before the scrape is made. I find I can get the D P-C down almost to C# using this method and it gets quite a bit of flat-chanter type of tone in the extreme case.
General speculation: I think this practice of carving chambers inside reeds is more prevalent among makers using harder cane and/or thin-walled staples. My guess is that the important principle is the internal airspace in the chamber, and that the method restores volume lost by changing to cane or staple types not used by the original chanter designer. However there may be a vibration effect; I just don't know.
"Your mileage may vary!"
david
The bore plots on my web site (and the posted X-ray) show that both the Quinns I measured have considerable under-cutting of the A hole in both directions. So does Phil Sexton's Mark Hillmann chanter which appears to be Quinn-inspired.
One of the things I've felt needs improving about the P-C is 2nd octave A stability. The pressure figures I posted state that octave A needs a bit extra pressure for safe rolls etc. and although the amount is not "great" still I've wanted to improve it.
I finally put 2+2 together realizing that A' was more stable with G' &/or F#' fingers off. This effectively enlarges the inside diam of the bore below A' -- but the undercutting downwards, underneath the hole, does this too. I'm sure several of you have pointed this out to me at one time or another in e-mail.
I've just made a nice improvement on a test P-C by under-cutting the A hole downwards. Perhaps this bore or those much like it have a wee instability right around there (more likely, elsewheres!) for which this has been found by others to be a convenient fix. It doesn't seem to have hurt the tuning; in fact on the P-C there is a slight tendency for the 2nd octave A to be flat, and downward undercutting often sharpens a 2nd octave note.
I used a high speed small diam rotary file, but a drill bit could be spun in an ordinary drill up against the underside of the hole to accomplish the same thing.
I'd estimate the angle at 20-30 degrees towards the bell (away from straight into the bore). I worked the bit upwards so that the top edge of the under-cutting just reaches the top layer of the brass tube core, so neither the outside of the hole nor any of the CPVC covering has been cut.
David Daye