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Hello everyone,

I've been working for a while on a new electric clavichord design. Here are a few pictures of the build:






I'm currently working on the pickups and would love a little help from forum experts, as electronics is not exactly my forte.

I want to design a first humbucking bridge pickup which for now, looks like the following:

1 — The 3D printed plastic bobbin.


2 — 10 cylindrical magnets inside each bobbin.


3 - Copper coil.


4 - 4 bobbins in a row, bobbin 1 and 3 contains north facing magnets (in blue), bobbins 2 and 4 contains south facing magnets (in red).


5 - A single and long pole piece of steel joins all the bobbins.


6 - Schematic view of the wiring that I came-up with. "S" means start of the coils, "E" end of the coils.


I've read articles about pick-up design and understood that in order for two coils to be in a humbucker configuration, one the coils had to be reverse-wound and one of the magnets had to have its polarity reversed. I based my design on this, but I don't know if the fact that my pickup design contains only one long pole-piece which contacts all the magnets will make the whole thing not work. I can always make 4 pole pieces but one long piece would be easier.

I'd be glad to discuss this design with folks here. I kind of need to know if this could work before I spent time building this  . As it's probably pretty simple for some of you here, I thought I should ask.

Thanks in advance, and don't hesitate if you wanna know more about this project.

Cheers,

Kevin

Hello everyone,

I'm a new member on this forum and this is my first post. I'm french, so please excuse any english mistakes, I'll try my best.

I'm a musician with a fine-arts sculpture/design background, and I've been working for about a month now on a homemade reed electric piano, mostly based on the Wurli 200A, as one can find quite a lot of informations online on this great instrument. Electric pianos are quite rare and pricey in France (a Wurly in good condition costs about 2500€), but this is not really what motivated the project. I just like going back and forth between music making and woodworking and thought it would be nice to build an instrument for my own use as a musician. I've got plenty of time, don't really feel like making music these days as I just released an album, so, why not?

I'm lucky enough to have a workshop with the essential machines and tools to work accurately with hard wood. I also have a fair stock of exotic wood (not sure what it is, probably padok) at my disposal, which could fit the task as it is very straight grain, almost doesn't warp with humidity changes, and is quite tough. A good friend also lend me a 3D printer which is gonna be helpful for making very small parts.

I'm creating this thread for two purposes. The first one is documenting the process for me and others to see, second is being able to ask very specific questions on parts, materials, etc., as this forum seems to be full of great people with lots of experience.

My idea is to make a sort of Wurly/Rhodes hybrid, basically a passive Wurly with electromagnetic pick-ups. I'm currently making a first prototype of a one-octave piano, from C3 to B3, and if it is interesting enough I'll be making a 64 notes version. I spent a good two weeks of reading every article I could find on the subject, and later came-up with a first 3D model.



The action is a copy of the 200A, based on the handmade drawings of the service manual, which might sound crazy but these drawings seems to actually have the right proportions, as I already built one action and it seems to work fairly well.



My plan is to start by building one complete action and fine-tune it until it feels perfect, and then hopefully build the rest. For now I made a first action, which is of course far from perfect. The jack spring (which makes the fly return to its home position) and the damper spring (which makes the dampers return and press on the reeds) are still missing, as I still have to try out different wire sizes/lengths/numbers of loops/shapes, and also ways of fixing them to the action parts.





In order to post stuff regularly and to do things step by step, for now my focus is gonna be on the action parts, so I won't talk as much in this first post about reeds, keyboard, pick-ups, sustain pedal, etc., but I'll obviously came to these later as I work on it more specifically. That said, I already prototyped a working electromagnetic pick-up with 3D printed plastic sleeves or holders, 3D-modeled the keyboard and the enclosure system, and also tried different reed shapes and materials (I might do different than Wurlitzer reeds, as their stamped shape is near to impossible to reproduce with common tools, at least without spending one year filing hardened spring steel).

So I hope this project might interest people here, and that some of you will be able to help answering very specific questions, as many will come! I also wanted to thank everyone on the forum who came with infos, as it's been a great place for me to understand all the parts functions of electric pianos.