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A loud, low cost cornemuse you can build from CPVC in 1.5 hours

Daniel Bingamon - 11:15pm Jun 3, 1999
MIMForum Staff

I wrote this a days ago, I wish to share it with the forum. The Soda Straws makes pretty cheap easy-to-make double reeds. (That in itself is another topic).


by Daniel Bingamon

Base Frequency: 130.81 Hz

Plays 1 Octave

Uses a Soda Straw reed

Parts List

2 1/2" CPVC Pipe 1st piece = 22.5 inches, 2nd piece = 2.75 inches

2 1/2"to 3/4" CPVC reducers

1 1/2" CPVC Coupler

1 3/4" CPVC Coupler

Super Glue, Pipe Cutter, Hacksaw or Coping Saw, Scissors, Drill and Bits, Sculpey or FIMO, A Soda Straw, 7/32" Inner Diameter / 1/4" Outer Diameter Brass Tubing, Exacto or Hobby Knife

A Cornemuse is similar to a Crumhorn except that it lacks the bend at the bottom. Many Cornemuses are usually softer than Crumhorns, except for this one. This Cornemuse has an attitude. It's loud a coarse.

This Cornemuse employs an ordinary Soda Straw as the double reed. Yes, I said a Soda Straw. The Soda straw should be able to fit inside the piece of brass tubing. Soda Straw do vary in size, but there are lots of fast food places out there to find them.

Building the Reed Cap and Mouthpiece

Cut a piece of the 7/32" Inner Diameter to 1" Long section. Cut a small piece of Soda Straw to 1/4" Length. Super Glue the 1/4" length of Soda Straw inside on end of the tubing, this will act as a container and stop for the reed otherwise called a "Staple Socket". Take the 1/2" coupler and cut it in half. Well, almost in half. Cut it slightly off center in order to preserve the middle wall inside the coupler, discard the shorter half. Take a 1/2" to 3/4" CPVC reducer super glue the cut-up 1/2" coupler to the reducer with the wall side of the coupler facing the 1/2" side of the reducer. Using the Sculpey or FIMO Material, make a plug that fits inside the reducer with a hole in that fits the "Staple Socket". Be sure to follow the instructions on curing this stuff properly. Super Glue this adapter in place, also super glue the "Staple Socket" inside the hole in the adapter with the "glued-in" Soda Staw pointing towards the cut-off 1/2" coupler. Place the 3/4" Coupler over the other end of this entire piece on the 3/4" side of the reducer.

At this point, it should begin to look like a Reed Cap. Place the other reducer 3/4" side onto the other end of the 3/4" Coupler.

Take the small piece of 1/2" CPVC pipe and cut a diagonal cut on one end to make it your mouth better. Optionally, you can fill in part of this mouthpiece beak with sculpey or FIMO material.

Making the Reed

Cut a Soda Straw to 2.5 inches in length. Flatten on end of the straw using a hammer. Cut the ends of this flattened side to a point that is 1/4" long. It should buzz at a high pitch by itself (like a toy), if it doesn't then make sure that it is flat enough and that the two piece line up together.

Drop the reed into the "Staple Socket" and place the short 1/2" CPVC pipe over the reed. You now have the Reed Cap, Mouthpiece and Reed.

Making the Tone Body

Take the 22.5 inch 1/2" CPVC pipe and drill holes from the bottom going upwards according to positions and drill sizes below.

(metric numbers later)

Position Drill Size

5-5/8" 3/16"

6-1/16" 5/32"

6-7/8" 7/32"

10-1/2" 5/32"

11-7/8" 5/32"

12-5/8" 3/16"

One last hole underneath

13-1/2" 3/16"

You may have to adjust the holes slightly, also clean out the holes using an exacto knife. Anything inside holes that are this small will change the frequency of the note. That last hole underneath is not a register hole, it is tone hole for the thumb. It's easier to reach with the thumb.

Putting it together

Plug the side of the Tone Body tube where the holes are further away from the end into the Reed Cap on the side where the cut off 1/2" coupler was Super Glued in place. Do not glue the tone body to it. It must be moveable for tuning.

Adjustmenets, Comments

You may cut the Soda Straw length to coarse adjust the tuning as well. The thing is that if you make a mistake, Soda Straws are cheap! Each playing session, you will have to remove the reed and squeeze it because Soda Straw reeds tend to straighten out at the flat spot. You can sand the leaves of the reed to make it easier to play.

Playing it.

It takes some breath to play this. It will wake up your Crumhorn consort. Cornemuses and Crumhorns are sensitive to air pressure changes. You can actually change the note which you are playing to the the next note just by blowing harder. It takes some practice to play a Crumhorn or Cornemuse with good air regulation.

Final Comments

I have thought about using another piece of brass tubing to fit around the reed and then it could be pinched with a pair of pliers in the way bridle wires are used on real double reeds. This could possibly keep the reed from unflattening with time. I hope to design an entire Consort set eventually. The reed design here could be used in Bagpipe drones if some of the above ideas are employed.

Credits to Fran Holland and Robin Goodfellow through the EMI June 1999 issue, the article, "Straws in the Wind". Whose ideas would not make it possible to have a Cornemuse that can be built in about an hour and a half.

I've written this as simple and procedural as I could. Hopefully, I'll have pictures shortly.

Julian D. Barton - 08:22am Jun 4, 1999
MIMForum Staff

Daniel, thanks for bringing up the soda straw theme. They do make pretty decent reeds for a number of novelty projects. When you flatten the end of the reed try to also have the plastic taper to a very thin edge. I just do this with my teeth. I just put the straw between my front teeth and draw it out under pressure. This will flatten and thin the end of the straw. When you are done the end will be rather irregular. Use a single edge razor and trim the end straight and even (or use scissors) it should help the response quite a bit.

I'll have to find time to make one of these. I'll let you know how it works.

You can also make a pennywhistle (which would actually cost about a penny) by using a straw and cutting small toneholes with scissors. Simply flatten the straw a bit and make a small angled cut. Now cut at the opposite angle towards the first cut. This is the same technique used for making snowflakes if that is clearer. It produces diamond shaped toneholes but hey it's just for fun.

Another fun demo for school kids is to make the straw reed then while playing it, cut off 1/2"-1" pieces while you are playing. It vividly demonstrates the basic principle of "shorter is higher". Also all of those flying pieces of straw really makes the kids laugh.

Daniel Bingamon - 06:19pm Jun 4, 1999
MIMForum Staff

Two or three straws connected together make a really nice bass sound.

Timo Teufert - 05:11pm Jun 7, 1999

Hi Daniel!

Thank you very much for this manual. I had some difficulty in finding 1/2" CPVC tubing over here in Germany. The smallest diameter I could find was 16 mm. I used a practice-chanter-reed (plastic) instead of the Soda Straw, wich gave a nice low C on an instrument according to your plan. But the other holes didn't work at all, especially the upper holes for the left hand. They seem to be too close together (compared to a tenor crumhorn I made from an EMS kit). So how should I position the holes on a pipe with 16 mm diameter? Should I use another length? Or will it not work with my reed? I would really appreciate any help. Plans for an entire Consort would also be great!

Timo Teufert

Daniel Bingamon - 11:13pm Jun 10, 1999
MIMForum Staff

The frequency of the reed works with the length of the instrument. Shortening the length of tube between the reed and the first hole might help. It was pretty much designed around the soda straw. The nice thing though, it can be made functional in a very short time.

I also suspect that the 4th tone hole on my design might require a little resizing.

Charlie Jackson - 02:10am Jun 11, 1999

The "attitude" or coarse sound may be due to the large bore diameter of the tube, instead of from the straw reed, if I understand the dimensions properly. Lucite tubes come in 1/2" OD and 1/4" ID and have provided nice sounding instruments for the Tenor range. Bending the tube to make a crumhorn does not change the tone color.

With a cornamuse reed from a London Early Music Shop instrument, the volume and coarseness of tone can be changed a lot by openning up the reed near the staple.

Daniel Bingamon - 12:10am Jun 13, 1999
MIMForum Staff

CPVC doesn't like to be bent except by heat. PVC can be bent be softening in acetone.

This whole thing was designed to make an instrument in a very breif period of time and that anyone can build.

You have a good point about the "coarseness". Since the reed is abruptly opening from a small pipe into a relatively wide tone column.

Daniel Bingamon - 12:25am Jun 13, 1999
MIMForum Staff

Here is a picture of it:

Timo Teufert - 05:57pm Jun 13, 1999

Has anyone ever tried to make such an instrument out of metal (copper or aluminium tubing)?

Daniel Bingamon - 10:42pm Jun 13, 1999
MIMForum Staff

The Eric Reiswig Smallpipes use brass tubing for the bore. You could probably do the same here.

Timo Teufert - 10:13am Jun 14, 1999

Maybe I'll try it. Anyway, have you, Daniel, or someone else tried to paint or finish the CPVC pipes? This "cream colour" might look nice on an old Stratocaster, but on a (more or less) late-medieval wind-instrument... Would polyurethane be suitable?

Daniel Bingamon - 05:47pm Jun 14, 1999
MIMForum Staff

Polyurethane might work. Be patient with painting it. Give it a coat wait for it to cure and then hit it again. The bad thing about CPVC or CPVC is that if it gets scratched, it really shows.

Al Dodson - 12:50am Jun 16, 1999
Guitar player? Clockmaker (repair)

This discusion has led me to several hours exsperementing with straws as reeds. There must be some great lessons here for my son who has just started playing oboe; unfortunately I don't know what they are as I do not play reeds. He's having fun with them anyway.

I did find that pressing the ceases into the straw with a metal object like a butter knife (lay it flat) on a hard surface will help. Also the ends can be thined on sand paper. Thiner straws work better.Your wife will be afraid to go out to eat. <g>

Daniel Bingamon - 02:37pm Jun 19, 1999
MIMForum Staff

To use one of the old expressions from Compuserve forums: ROTFLOL - Rolling on the floor, laughing out loud. I told my wife about this one, she gave me a strange glance - she said that she may eat a separate table if I try this at the restaurant.

I've wondered about making a small pipe shroud to help it keep shape similar to bridle wires on tradional double reeds.

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