HELP ME! OMEGIA desk clock

Similar clock in this thread, there may be others.

I had to repair one of these some years ago and the only solution was to replace the motor with a modern quality quartz movement.

The main problem is the little drive wheel (rubber tire) gets worn down or disintegrates and there are no spares available.

I'll see if I can find anything in my records.

That was the clock I did for Linus, no way to repair the worn drive wheel and no parts available.

Here is the issue with the clock I did.
From my messages:


Oh well, at least we now know what the problem was.

But first a quick run down on "acceptance check".

Case is slightly crazed where exposed to light but should come up with gentle cleaning.
Bottom plate missing two feet (can use screws to replace and fit non-slip bumpers).
Door handle broken, will try to braze back on.
Dial has age shadow, maybe able to clean but will test a small corner first.
Dial has two gouges at the centre from careless hand removal.
Brass on case/dial surround is tarnished. Suggest gentle cleaning and not "Ooooo Shiny!" look.
Missing screws: 1 on battery case, 4 on back of dial edging.

So that was the state of the nation before I started on disassembly.

A quick check with a fresh battery showed that the motor would run, but not efficiently, so an electrical problem with the transistorised motor circuit.

While the motor would run (just), there was no expected "kicking" of the escapement lever which keeps the top balance wheel ticking to regulate the speed at which the drive wheel and shaft rotate to provide the "tick" of the movement.

A look into the top of the escapement showed that something was not good.




The motor has a shaft going to the escapement assembly and the pinion on its end turns a wheel with three "teeth" that kick the escapement lever to power the balance wheel as well as regulating the speed at which the driver shaft can power the hand wheels.

Here you can see the top of the motor shaft with its pinion. Not a big problem with it, but there is a lot of bits in the grooves that should not be there.




Here's a view showing the way the motor drives the escapement.




And there is the problem. The motor shat/pinion should drive a wheel (cog) just below the three impulse teeth, but there's nothing there except some "bits".

So after removing the parts the problem becomes obvious. It appears that the wheel that's driven by the motor shaft pinion, was made from an early plastic material that doesn't age well at all.




And a close-up. It should look like a nice round wheel with little teeth all around the outer edge.




So, there we are.

Unless I can find a replacement electric clock escapement that hasn't been made since 1960s, and the last parts stock sold off in 1985, there's no chance of repairing this movement. Add to that, if this part has an inherent design flaw, chances of finding a movement with that part will be slim.

From memory, it's less than 10mm diameter, made of rubber, so even TPU would probably be too slippery.

The problem is that the tire (rubber bit) is sandwiched between two tiny plates, the bottom sitting on the shoulder of the shaft and the top held to the shaft by the top of the shaft being peened over.
To replace the tire, the top of the shaft needs to be machined down, the top cap removed the tire replaced.

And then magic happens to secure the top cap again.

There are no teeth.
The part you need is a "rubber wheel on an axle" that hasn't been made for over fifty years.
I searched for months for parts without success.

That's the easy part.

That will be the hard part.


Replace the movement with a quality quartz clock movement.

I did find a complete movement some years ago, but the price was prohibitive and likely hasn't got any better.

Just found this, explains the issues with the Portescap and offers a solution.

May be of help to those needing repair.

https://harrishorology.com/blog/portescap-movement-service-secticon-clock-repair

Sorry I can't help much, I haven't touched one of these since 2019 and without the movement in my hands so I can see what happens I'd just be guessing.

I think the magnetic block is to stop the impulse lever from bouncing, it hold the lever until the next "flick" from the wheel.
It doesn't have any notches, as far as I know it's just a smooth circular rubber wheel.

Check out the video in the site I linked you to, there's a lot of information there.