photo above is from http://traditionalmusicinstrument.blogspot.com/

Alphorns, or Alpenhorns, make a warm, deep, sonorous, mysterious sound; their history is old and married to the Alps.  They are beautiful pieces of woodworking also, and are rare to see in these parts.  I wanted to play one, so I set out to build one.  Here is how I built my Alphorn.

Firstly, I was able to find no drawings of Alphorns, so significant research, and making of drawings was needed.

I found all the data I could on the internet, and also made my drawings by scaling from photographs.  There are still master Alphornbuilders out there  and the links below show some of them.  These were helpful sites:
https://www.youtube.com/watch?v=UTyC7DfWeSo
https://www.youtube.com/watch?v=eGRhsmSiywc
https://www.nendazcordesalpes.ch/en/alphorn/the-making-of-an-alphorn
https://www.alphorn-neumann.com/alphorn.php
​http://www.alphorn.ca/
http://www.flyby.ch/alphorn/geschi_e.htm
and here is a photo of Alphorns:

Alphorns being played in Switzerland; photo from Wikipedia.

All my research yielded no actual drawings showing the dimensions to build an Alphorn, but I was able to make notes of many of the dimensions I needed from my web research. When it is built, I will play it and we can all see how that goes, I will let that speak for itself. I decided to try and build an F# 353cm long (11'-7" long) Alphorn. The mouthpiece seems fairly similar to the trombone, which I play, and for reference the length of tubing in a trombone is about 9 feet. Regarding the shape of the Alphorn bell, I drew this from photos. I still had questions on the length of the main trunk of an F# Alphorn, so I wrote an email to an Alphorn player, William Hopson, who gave me the great advice to build it a bit long and then trim it down to tune it.

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A Brief History of Alphorns

These beautiful horns were built from spruce trees growing high in the Alps and were used by Alpine shepherds 2000 years ago to communicate and to make music; a tradition which continues today.  Long ago, builders would choose a high mountain tree that grew out of a steep mountainside.  After growing out from the mountainside, the tree would turn and grow vertically toward the sun, and the shape of the tree was used by the early builders of Alphorns to make the shape of the horn.  The trees were split in half, carved out, the halves reattached, and the horn made.

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Alphorn Drawings by a Novice Alphorn Builder

Now then, onto the alphorn I will build. After all my research, I drew the drawings for building an Alphorn, below by hand to best match what I had learned.  The shape is as traditional as I could make it, but the construction method I will use is not traditional. I will make my Alphorn tube using the birdsmouth joinery method used by shipbuilders to build ship masts. I used this method to build the Sitka Spruce mast on my sailboat. It is very strong joinery and I will use it to build my Alphorn. These are decidedly European instruments, so I used the metric system in my drawings.  I do not claim to be an authority on Alphorns, this is simply my documentation of the one that I built.

Feel free to use these drawings for building an Alphorn for your own use, contact jason@argobuilder.com for permission to reproduce these drawings for any purpose other than building an Alphorn for your own use.

MATERIALS:  This Alphorn will be built from Sitka Spruce from the pacific northwest, hard maple from I tree I cut down years ago, and Black Walnut.  

GLUE:  I will use Titebond III glue for most of this project.  In three places, I will use a 2-part epoxy: I will use two-part epoxy to glue the end rings to the bell, to glue the bell to the long trunk, and to glue the foot to the bell.

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Making an Alphorn Mouthpiece

Maple is a traditional wood for the making of an Alpenhorn mouthpiece.  I had cut down a hard maple that grew on my property in Thiensville, Wisconsin, about eighteen years ago, and I still had some sections of the trunk left.  I made this mouthpiece from that tree.

Hard Maple blank , cut into a rough octagon before turning.

The start of turning the Alphorn mouthpiece.

Checking dimensions with a caliper, from drawing to the piece.

Checking dimensions from the drawing vs the work piece.

The Alphorn mouth piece is coming along.

Here is the rough-turned and rough sanded Alphorn mouthpiece, removed from the lathe.

Ends trimmed. Now I need to carve out the bowl and drill the bore, which will be tricky and I could imagine myself wrecking this first try at making a Alphorn mouthpiece; we shall see.

I carved out the alphorn mouthpiece bowl with a dremel tool.

Drilling the bore through the stem of the mouthpiece

Unfinished alpenhorn mouthpiece. Now I will finish it with Tung Oil.

Alphorn mouthpiece, made from local hard Maple, with Tung Oil finish.

Wooden horn mouthpiece, for Alphorn.

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Sitka Spruce

Sitka Spruce is an amazingly clear and straight, vertical grained wood, with excellent strength-to-weight ratios. Due its high strength, low weight, straight grain, and minimal knots, Sitka Spruce is used for aircraft framework (including the Wright Flyer), sailboat masts, and it is also renowned for sound-quality in instruments.

The tree itself is awe-inspiring. I plane and carve and cut this wood with the utmost respect, and have only used it for making such transcendental things as sailboat masts and spars, and musical instruments. The Sitka Spruce grows in the Pacific Northwest of the USA and Canada. The Sitka Spruce is one of the few species on earth known to grow over 300 ft tall (over 90m). The forest of Sitka Spruce has been vastly diminished by logging, but on a positive note, it is considered a "species of least concern" regarding potential for extinction of the species. The largest of these trees were cut down in the past before the giants could be measured. The older trees do not even have branches on the lower 100 feet of the trunk. The Queets Spruce in Olympic National Park is 450 years old, and some Sitka Spruces are over 700 years old. All wood is special wood in its own way, and this also is very special wood.

Sitka Spruce, growing in Olympic National Park.

....and so, somberly, we reach the part where the tree (not necessary the tree in the picture) has been chopped down and milled into lumber for our use.  I will turn this into an Alphorn, which is a noble end.  I wish I could be of such a fine use after I bite the dust.   I would be happy to return to the soil, and to do as Whitman suggests: from Leaves of Grass: "I bequeath myself to the dirt to grow from the grass I love, If you want me again look for me under your boot-soles."  All trees are special, and these Spruce are special even amongst all trees; I will make the most of the wood.  

Two 4/4 x 6 x 17' rough sawn Sitka Spruce boards from McCormick Lumber in Madison Wisconsin. Dimensions are 1.0" x 6" x 17'. These are perfectly straight, straight and vertical grained board with no knots.

Surface planing Sitka Spruce for the Alphorn.

Here you can see why this is such a sought-after wood; tight, vertical, straight grain, with no knots over a 17' to 20' length.

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Making the Alpenhorn Bell

The bell will be built of Sitka spruce from laminated sections as shown below. After gluing the pieces together, I will carve them to round.

Sitka spruce pieces , cut to shape to build-up the laminations needed to make the Alpenhorn bell.

Using many clamps....

Here's what a little over one half of the bell laminations look like stacked up.

End-view of one half of the small end of the bell, rough at the initial glue-up stage.

Here are both halves of the Alphorn bell at the stage of initial lamination glue-up.

End-view of one half of the large end of the bell, at the initial glue-up stage.

Large end of bell, not glued up yet, but showing that the halves match nicely.

I drew the line for the end of the bell and cut it using the Japanese pull saw. Do this carefully.

Trimming the small diameter end of the bell to length.

I made these templates out of 1/4” plywood. I will use them to trace the bell OD and ID onto the wood.

With the two halves clamped (but not glued!) together just right, I traced the final bell shape onto the ends using the templates I had made.

Then I used a mortise gage to mark the wall thickness along the length.

Carving out the inside of the Alphorn bell with chisel and mallet! I had an odd number of laminations, so this “half” of the bell is less than half of the bell.

I have left the OD uncarved as I carve out the ID, in attempt to maintain strength of the wood as I chisel away from the ID. The strength of the chisel blows will surprise a person, as this Sitka is strong. WATCH THE TREE GROWTH LINES and understand that that woods splits along the grain. After a short time carving, a person will understad this and use it to their benefit. I am using my straight chisels for almost all of this carving because straight chisels are soooo much easier to sharpen. As I get closer to the finished ID I will use my curved chisel.

Hand carving with chisels continues.

Still carving, carving, carving. Getting there. Soon I will start rough carving the outside of the bell.

Now I have to sand them smooth, but first I will carve the outer surface of the bell.

This half of the bell is flipped over and I will start rough carving the outside with a chisel.

Rough carving of the OD is underway.

Chipping away at the outer surface of the Alphorn bell.

Sitka is pretty tough, especially for a softwood tree. Working with sharp tools is a necessity. Today I took a break to sharpen chisels.

With chisel carving done, I will now smooth the exterior of the bell with a Shinto Rasp. The Shinto rasp is an amazing tool.

Here is one half of the Alpenhorn bell, with ID rough carved , and OD carved and rasped smooth.

Now I will start carving the outside of the other half. One tricky aspect of carving this bell is holding it tight so that it doesn’t move as one carves it. Note the support blocks that I have screwed into the work table. After implementing this method of securing the workpiece, the carving became more efficient.

Here are the two Alphorn Bell halves, resting together. Next I will sand the insides, and then I will glue the halves together.

I used a 3" diameter x 3" long sanding drum, chucked in a 1/2" handheld electric drill to sand the ID of the bell.

Titebond III glue applied to both halves of the alphorn bell.

Moment of truth! It fit together nicely, this was a big moment in the project.

I selected a nice local wood, a dark hardwood, Black Walnut, for the ring at the end of the bell. This is a 10.5" x 10.5" x 3/4" glue-up.

The exterior of the bell has been rough sanded with a random orbit sander.

The ring assembly on the end of the bell will consist of two hardwood rings, a Black Walnut ring will fit up to the face of the endgrain of the bell, and the hard Maple ring will fit over the OD of the end of the bell.

Cut the OD of the ring, then I used a router to round over the edge, then used a sabre saw to cut out the ID.

Maple ring ready for installation

Black Walnut ring, ready for installation.

I used a two part epoxy to glue the rings to the bell and to each other. It's tough to see in the photo but the small end of the bell is resting up against a wooden brace to hold it in alignment so that the big face of the bell is laying flat on the ring. Be sure to wear latex gloves when working with epoxy.

Using a rasp to shape the flare of the ring at the end of the bell.

Sanding, sanding, sanding...

Rough sanding is all done.

I measured out the approximate size of the space available for artowork on the top of the bell, and arrived at approx 8" Long x 2" at the narrow end x 5" at the wide end. I sketched out that area on a piece of paper and then sketched out the floral theme I will use. I drew springtime wildflowers that are native to my home here in Wisconsin; from left to right: Wood Violets, Trillium, and Buttercups.

At the large end of the trunk and the small end of the bell, I will epoxy Black Walnut ring flanges over the O.D. for reinforcement of that joint. Here are the rings in contruction.

Hardwood flange dry-fit on the end of the bell.

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Making the long trunk of the Alpenhorn

I built the long trunk (not sure the correct terminology for the long tube of the Alpenhorn, but I am calling it a trunk) of the Alphorn from Sitka Spruce, using the Birdsmouth construction technique, as shown in the drawings above.  Here's how I did it.

IMPORTANT NOTE:  I made the trunk of the Alphorn 6" (15.24cm) LONGER than shown on the drawing.  The extra length was added to the mouthpiece end of the trunk.  If I would have added the extra length to the bell-end of the trunk, the diameter would not have been correct where it meets the bell.  I will trim the length of the mouthpiece end later when the horn is assembled in an attempt to tune the horn to F Sharp, hopefully this works.

4/4 x 6" x 10.5 foot rough sawn Sitka spruce being ripped into three 2" wide pieces. I cut one more 2" wide strip from a second board of Sitka Spruce.

Then I carefully ripped each of those four pieces down the middle to wind up with eight 1/2" x 2" x 10.5' pieces.

I will call these pieces that make up the trunk of the Alphorn, Staves. At this point I surface planed the staves to precisely 1cm thickness.

The staves are ripped to 43mm width. So now I have eight 10mm x 43mm full-length staves.

To cut the "birdsmouth" into the staves, carefully set the depth of the tablesaw, and carefully set the angle to 45deg and the fence in place. Test the cuts first on a piece of scrap wood cut to the exact same dimensions as the blank staves.

Here are the eight staves with the birdsmouths cut in.

I used a long straight-edge to draw out the taper onto the first stave.

I cut the taper into the stave using a Sabre Saw and then traced out the taper on the remaining 7 staves.

Here are all eight staves with the birdsmouths cut and the staves tapered to shape.

I cut three cradles from scrap plywood to assist in assembling the birdsmouth staves. I made sure they were perfectly level and straight.

First two staves of the birdsmouth Alphorn trunk glued together. Use ample glue and work fast!

Three staves in place.

The staves are vertical on either side. I made an inner support circle to help place the final staves on top, you can see this in the next photo, below.

I made the inner support circle from scrap wood including a little handle to make it easy to retrieve, and will remove it once all the pieces are locked in place.

Using zip ties to clamp the pieces together. Some jostling and pounding of the staves is necessary to make sure they are all seated in the birdsmouths. I am working down quickly with the zip ties from the large end to the small end.

The trunk of the Alphorn is glued up using the birdsmouth technique. I pushed a damp rag through the bore to remove any glue blobs. I will let it dry a good and long time, and then will get to work planing the OD round.

I used the Japanese pull saw to trim the big end of the trunk to length.

Here is a view of the cross section of the birdsmouth joinery on from the cutoff piece from this Alphorn.

I let the glue dry a full 24hrs and then planed used a plane to round off the Alphorn trunk.

Here is the Alphorn trunk planed to round. Next I will sand it.

Birdsmouth Alphorn main trunk, planed to round, and sanded.

The large end of the trunk and the small end of the bell, will both be fitted with hardwood ring flanges on their outer diameters. These will be epoxied on, and will in turn be epoxied together to attach the trunk to the bell. Here are the Black walnut flanges being made.

Hardwood flange, dry-fit on the O.D. of the large end of the Alphorn trunk, where it will meet the bell.

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Attaching the Bell to the Trunk

First I used two part epoxy glue to glue on the hardwood flanges to the trunk and bell. Be sure to wear latex gloves when working with epoxy.

I let the epoxy on the flanges cure for about an hour. At that point it was well set but not at all fully cured. This was the point I wanted to glue the trunk to the bell, as I will get a good chemical epoxy bond on all faces of the epoxied joint. I gathered up a bunch of spring clamps. See the plastic covers on the jaws of the spring clamps? Take those off beforehand....they were too slippery and kept allowing the clamps to slip off, so I had to remove them in a hurry during the glue-up.

Alpenhorn bell epoxied to the trunk using a flanged joint.

So for the first time I got a view of the whole alphorn! Next I will tune it by cutting down the length at the mouthpiece end of the horn.

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Tuning an Alphorn

The only way to tune an Alphorn is to make it longer or shorter.  When one plays an alphorn, the variation in pitch comes from the embouchure and frequency of vibration and airflow created by the players mouth and lungs, but the natural tuned pitch of the instrument is set by the maker during tuning, by cutting it to length.   For this reason, the instrument is made a bit longer than needed so that it can be trimmed down in length to tune it.

Now, fair warning, the first clip below is the very first time I played an Alphorn, so my technique is not good.  I was curious if the pitch would be changed by attaching the bell (I assume the extra length of the bell will lower the pitch a bit), so after the trunk was glued up, I took it outside and played just the trunk, as shown in the video below.  I used a digital tuner and found the trunk itself played a G!  So as it stood the horn is a half step high with just the trunk.  This made me nervous, as making the tune lower would require adding length which I cannot do.   After I attach the bell, I will play it again and hope that the addition of the bell lowers the overall pitch by a at least a whole note.

Well, I attached the bell and it made the Alphorn one full note lower in pitch, I was very glad for this.

The ID of the inlet end of the Alphorn was larger than I had designed for by a bit, I must have cut my staves a tiny bit to wide at this narrow end. The bell end of the trunk was the perfect design diameter... The result was that I needed to create a block with a bore drilled into it for the mouthpiece to fit snug into. For tuning, I used this small block.

I trimmed the trunk to length with a Japanese pull saw.

With the final length cut, I made this 6" long block to fit perfectly in the end of the Alphorn, it has a 14mm bore, and will be glued solid into the inlet of the Alphorn.

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The Mouthpiece-End-Ring,  the Foot, and Wrapping the Alphorn with Rattan

I found this nice thick solid piece of scrap Cherry in the shop, it is the center drop from a hole saw cut from a project a couple years ago. I will use it to make the little reinforcing ring near the mouthpiece.

Boring out the ring using the drill press, the only drill bit I had that was close in size to what I needed was a spade bit....not the best drill bit for this type of cut in a chunk of hardwood, but it's what I had. I was at least sharp, and it worked.

The hole from the drill-bit was too small, so I used a little drum sander chucked in the drill press to enlarge the ID to fit the Alpenhorn. I decided I wanted this ring to be about 75mm (3") down from the inlet end of the horn, which is a bit farther down that shown on my drawing.

I forgot to get a photo of this next step, but I used the bandsaw to trim the O.D. down to about 44mm.

I used the drum-sander chucked in a hand drill to carve the concave curve into the ring, then I handsanded the piece down and rounded the edges.

Finished ring, made of solid cherry, for the inlet end of the Alphorn.

Here is the ring glued in place with Tightbond III glue.

I rasped and sanded the flanges where the bell attaches to the trunk.

The foot of the Alphorn

The Alphorn is fitted with a small foot on the bottom of the bell, which lifts the horn out of the grass to protect the bell and make sure the sound can exit the horn unobstructed from low ground cover.

I carefully cut a template out of cardstock and made sure that the curve of the top of the foot matched the bell perfectly.

I made the foot from 4/4 Sitka Spruce, with Black Walnut pads on the bottom. The cradle of the foot is cut at an angle so that the feet will be level with the ground when the horn is played.

The foot is adhered to the bell with two-part epoxy glue.

Wrapping the Alphorn with Rattan

I will wrap the trunk of my Alphorn with 1/4" half oval basket reed.  This fibrous material is very strong in tension.  

This is 1/4" Flat Oval Reed, which is used for basket making or chair-wicker, this is what I will use to wrap my Alphorn.

The rattan arrives in coiled up bundles. Each piece is 8-14' long. (240-430cm)

I started wrapping the Alphorn trunk at the mouthpiece end, just down from the hardwood ring. Notice where the wrapping just starts on the left that I carved a long taper into the reed to start the wrap. I glued and clamped this down with a spring clamp and started wrapping. I watered down Titebond III glue applied it to the OD with a toothbrush prior to wrapping on the rattan. I don't want messy blobs of glue squeezing out onto the OD of these wraps, It would be a nightmare to try an sand the outside of these wraps while maintaining their curved profile. The watered down glue has worked perfect.

This is a photo of a 14 foor (430cm) length of rattan wrapped around the narrow end of the Alpenhorn. As the diameter gets larger the horizontal coverage of each length of rattan will decrease. One learns many things building an Alphorn, and one of those things is just how many splices of rattan wrapping it takes to wrap an Alphorn.

The spring clamp is holding the starting end of the rattan. Here I am applying watered down glue with the toothbrush on a section of the trunk prior to wrapping that section.

The clamp on the left is holding the starting end of the rattan wrap, the clamp on the right is the end of the length of the piece of rattan. I am using spring clamps which I leave in place for an hour, after which I splice on the next piece and move forward.

For the splice I taper down the reed from the top of the reed to the bottom on both pieces to be joined, then I use Titebond III (not watered down for the 1st inch of the wrap, and clamp the splice joint for an hour before unclamping. In the middle of this photo you can see a splice of the reeds. There will be more of these than I thought, as each reed only gets you 6-10" of distance along the horn length. I am locating all the splice joints on the bottom of the Alphorn trunk.

I saw some horns with a short section of wrapping on the small end of the bell, and I liked the look of that, so I did that. The spring clamps at the bottom of the picture are not being used to clamp the walnut flanges together, they are being used to press the narrow leading edge of tapered rattan wrapping against the trunk to keep it from moving. I located the end of the wrapping on the bottom of the bell where it will not be seen.