Acoustic Ergordica Build Guide

Tenor Acoustic Ergordica

On this page, I’ll show you how to build a tenor acoustic ergordica.

Please note this build guide is a work in progress and that it requires skill to complete. By accessing this build guide you agree not to hold me accountable for anything that might go wrong as per the terms and conditions of this site. If you have any suggestions, please let me know in the page comments.


Below is a list of parts needed to assemble a tenor acoustic ergordica. If any of the parts are out of stock, be sure to check the alternate sources listed in the captions. Some of the links below are affiliate links and proceeds go to further ergordica development at no extra cost to you.

2 X Swan Melodica for parts, Alternate Source
28 X Torsion Spring (0.16″ OD, 0.017″ Wire Size, 0.5″ Leg Length) Alternate Source
3/8″ Wide, 1/8″ Thick Neoprene Gasket. Alternate Source.
#2 5/16″ Thread Rolling Screw for Plastic (28 screws required). Alternate Source.
3D Printed Parts by Adams3DShop (See Step 1 for alternatives)
Gummy Bears for Rewards Along the Way


Below is a list of tools for the build.

  • Cordless Drill
  • High Speed Drill with Cutting Wheel. Alternatively, angle grinder or ban saw
  • Phillips bits various sizes
  • Phillips screw driver
  • Scissors
  • Vice
  • Safety Glasses

Step 1: Acquire 3D Printed Parts

You can acquire the 3D printed parts in multiple ways. The easiest is to buy them from Adams3DShop. He has kindly agreed to list the parts on his shop page and he’ll print them out when someone orders them. He uses the exact same 3D printer I used for development (Prusa i3 MK3S), so this is the best chance of getting the parts as I intended them.

3D Printed Parts by Adams3DShop
3D Printed Parts FilesCreative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (ergordica invention is patent pending).

Alternatively, you can send the files to a shop of your choosing, such as 3DHubs. The FDM process with PLA material works fine and is the cheapest option. You can probably get by with 300 μm layer height for the chamber and reed pan, which keeps the time/cost down, though I haven’t tested this myself.

Lastly, you can print the files out yourself. If you don’t have a 3D printer, you might check your local library. Know though that these files can take a couple days of print time! Make sure to turn on support material for the chamber (I like to set interface layers to 0). Also, you might want to use Gyroid infill for the reed pan to strengthen the region around the screw holes (Adams3DShop does this).

Whatever route you go, make sure to get the correct quantities of parts as listed below.

  • 1 Chamber
  • 1 Reed Pan
  • 16 White Keys
  • 12 Black Keys
  • 12 Clevises
  • 2 Half Clevis A
  • 2 Half Clevis B
  • Step 2: Prepare Reed Plates

    Preparing the reeds is, in my opinion, the trickiest part of the build. After this step it’s pretty much just assembly.

    Disassemble the melodicas and remove the reed plates, keeping them arranged as they were when attached. Melodica One will provide the reeds for the left side of the ergordica while Melodica Two will provide the reeds for the right side of the ergordica.

    Assume the reeds of the Melodica are numbered from M1 (F3) to M37 (F6) as in the above pic. Now note that there are four runs of reeds on the ergordica: Left Low, Left High, Right Low, and Right High. The mapping from the Melodicas’ reeds to the ergordica’s are as follows:

    • Ergordica Left Low: Melodica One Reeds M8 (C4) through M14 (F#4)
    • Ergordica Left High: Melodica One Reeds M20 (C5) through M26 (F#5)
    • Ergordica Right Low: Melodica Two Reeds M2 (F#3) through M8 (C4)
    • Ergordica Right High: Melodica Two Reeds M14 (F#4) through M20 (C5)
    Labeling of reeds from 37 key melodica (M) to Ergordica (note that the white areas on the reed plates in this image are from oxidization from moisture, it’s from a well used Ergordica!)

    Each of the runs has to be cut from the reed plates of the melodicas. To prepare a run of reeds, break off the unused adjacent reeds from the start and end of the reed run (double check before breaking!). Then put the reed plates in a vice and use the cutting wheel in a high speed drill to cut the reed plates where you broke the reeds. Definitely use safety glasses for this step and proceed at your own risk as per the terms and conditions of this site. If you have access to a ban saw or angle grinder, those would probably work better, though I haven’t tried them.

    Note that one of the reed runs (Right High) has to span two reed plates. There’s no way around that as long as we’re using melodica reed plates.

    Step 3: Attach Reed Plates

    Now that you’ve prepared the reed plates to form the four reed runs, you can screw them into the reed pan. You can either use the screws that came with the melodicas or some #2 x 1/4″ pan head screws. Note that it’s important to use stainless steel screws as there will be a lot of moisture touching these screws.

    Note that the side of the reed plates without the reeds is the side that sits against the reed pan. Also, the left and right reed runs face opposite directions, with the free side of the reed facing outwards.

    Step 4: Attach Gasket

    Attach the gasket to the rim of the chamber.

    The holes in the gasket are created when you screw the chamber to the reed pan.

    Step 5: Connect Reed Pan to Chamber

    Make sure to use the torque limiter on your cordless drill to prevent over-tightening for this step as otherwise you can crack the plastic parts (if you don’t have one, just be extra careful). Use either the large screws that came with the melodicas or other #4 x 1/2″ tapping screws to connect the Chamber to the Reed Pan. Gradually tighten the screws one at a time to get even pressure across the gasket.

    Step 6: Key Assemblies

    Each key assemble consists of two keys with gaskets on the faces, a clevis, two torsion springs, two of the small screws from the melodica (or other #2 x 1/4″ pan head screws), and two of the #2 x 5/16″ pan head screws.

    Some key assemblies will have two white keys while others have a black key then a white key (or vice versa). And the key assemblies for the four C keys only have a single key. Use the picture below to guide you during assembly.

    For each key assembly, first attach a section of gasket to the face of each of the two keys. Next insert a leg of a torsion spring in the slot of a key arm underside. The other torsion spring leg then slides into the slot on the face of the clevis. Put the #2 x 5/16″ pan head screw in to keep the key in position. Do the same for the other key of the assembly.

    Repeat for all key assemblies. Note you want to complete one single key assembly and attach it to the top of the reed pan (next step) before finishing the rest of the key assemblies in order to hone your technique. This is probably the most time consuming part of the build, so you might want Gummy Bears for rewards.

    Step 7: Attach Key Assemblies to Reed Pan

    Use the small screws from the melodicas (or other #2 x 1/4″ pan head screws) to connect the key assemblies to the top of the reed pan. Try to hold the key assembly in one hand with both keys fully retracted while the other hand holds the screw driver. Each key should create an airtight seal with the reed pan key hole via the neoprene gasket. If too much air is getting through, try reattaching the key assemblies. You can also use electrical tape to cover all but one hole at a time to trouble shoot. Note that the seal will improve over time as the neoprene compresses. Eventually you may want to replace the gaskets if they compress too much.

    Step 8: Mouthpiece

    Put in either the mouthpiece or the blow tube and give it a try!

    Step 10: Tuning

    There is a good chance your ergordica could use some tuning. You can tune it pretty much the same way as a melodica (google melodica tuning). At some point I’ll come up with some more specific instructions for tuning an acoustic ergordica.

    That’s it!

    So, what did you think? I know it’s a kind of challenging build. If you have any suggestions on how to improve it or any related thoughts at all, please tell in the comments below.

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