Replacing the motor in a chord organ?

[David Blackman]

Hey all -

I'm on a quixotic quest to fix up a Farfisa Microorgan I got for free off craigslist.

Story so far
- Took apart the organ, took apart the motor, discovered its brushes had completely worn away
- Bought replacement brushes, slotted them in, turn it on, motor spun for a second, released the magic smoke, never turned on again.

Now, my new plan is to *replace* the motor. It shouldn't be that hard to find a 110v motor with a 4mm shaft and a ~3000rpm speed, right?

I cannot for the life of me find a reasonably priced motor that I think will fit.

My current beliefs about the motor
- it has a 4mm shaft
- it's a "universal motor" - meaning it runs on AC or DC - I believe this to be operating on AC because I see no transformer - https://www.reddit.com/r/MusicElectr...eb2x&context=3
- I couldn't figure out what RPM I should be looking for, but it seems like the vast majority I read about are in the ~3000+ rpm range. I read about this similarly looking organ https://www.reddit.com/r/AskElectric...rmophone_reed/ which helpfully has an RPM reading on it of 2600rpm - which I guess makes it a 2 pole motor. This thread also suggests it's a "shaded pole motor"
- when I search aliexpress for 2600rpm shaded pole motor I find this perfect fit ... except it's 220v and I live in the states ... https://www.aliexpress.com/item/3256...ct.mainProduct

I'm at a loss here. It seems to me like 70 years after this organ was made, I should be able to find a cheap common motor that can replace it, but I'm coming up blank.

I really don't know a ton about electronics, just enough to be dangerous, so it's entirely possible I'm looking for the wrong thing / worrying about the wrong thing.

Thanks in advance for any help!

[Larason2]

Quixotic is just the right word! You're right it's going to be nigh impossible to find the right motor for a price that isn't ridiculous. The truth is that the electric motors that came in these were the most expensive component in the 70's, and since then the price of copper has increased a lot. Look at this one for instance:

https://www.electronicsurplus.com/mo...e-phase/page/3

Just right in every way, except the price! Perhaps if you bought an inexpensive electric fan for the motor? Also, do you have any thrift stores nearby? You might find something there that's suitable to gut for the motor. The RPM isn't that important with reed organs, it doesn't determine the pitch.

[nutmegct]

In every area I've lived in the USA, there's always an electric motor (and car starter motor) repair shop.

Google "electric motor repair near me" and see what happens.

Each usually has hundreds of old motors, and can completely rebuild a dead motor.

Tom M.

[Larason2]

I didn't think about that! Never had a starter motor go bad. I wonder what they charge for the service though!

[myorgan]

Great advice, Tom! My thought was to temporarily hook it up to a vacuum cleaner, either output or input depending on whether it's suction or pressure, and see what happens. OTOH, it may blow out any bellows you have, and that would cause a problem.

Michael

[turf3]

You'll almost certainly have to adapt something.

If you find a 220V motor that appears to fit and work, a small 220/110V transformer is cheap. This is probably a 200W or smaller motor.

It can definitely be done. You'll just have to search. A lot.