TWEMCO BQ50 running too fast

[brtn75]

Hello Flip Clock community,

Thank you for welcoming me on the forum and in your community!

I own a TWEMCO BQ50 flipclock which worked perfectly for almost one decade but since few weeks, my clock started running faster than expected.

The time shift was nearly invisible at the beginning but the more the clock turned, the more the shift increased.
Finally, after few days of use, the minutes were scrolling 4 by 4 (the minutes were triggered 4 times successively).

A watchmaker suggested me to inverse the batteries polarity in order to reset the quartz movement.

This option seemed successful at the beginning but few days later, the same problem occurred again.

I’ve tried to contact the manufacturer TWEMCO but my emails remain unanswered.

Have any of you ever encountered this problem and would you have a solution to fix it ?

Thanks

[Johan de Jong]

If I understand correctly the minutes instead of flipping just once are flipping four times in a row? And that happens every minute? That's a really weird issue.

I have a Twemco BQ50 myself, and had a different issue: it was running too slow. I don't know if it is of any help, but here is my post on that: https://www.flipclockfans.com/forum/...0-running-slow I have to admit that after my initial euphorism I later found that it still sometimes seems to run slow overnight.

Now thinking of your issue, here is a theory:
The timing is quartz controlled. Each minute it switches on the motor to flip the minutes. I believe that inside the motor assembly there is also a switch to turn the motor off after it has flipped a tile. If that switch or mechanism is not working properly it may keep running for too long and thus flip 4 tiles instead of one. To know for sure would need to open up the mechanism. That though takes some technical skills, so you should only do that if you are sure your skills are up to it.

[brtn75]

Hello Johan,

Thank you for your answer and your help.

You understand the situation correctly. As you said, the problem seems to be caused by a control disfunction.

The 4 tiles flipping plus the progressive time shift (which occurs before that) leaves me to believe that there is something wrong with the quartz.

I had a look on your post. Apparently, in you case, the setting of the potentiometer didn’t solve your problem.
May be a complete change of the quartz could be an issue? if it’s possible to find a spare component and of course if the cost is affordable...

[flipoclock]

I do not know this clock very well, is there a 'normal' quartz inside? You could try to reach out to Twemco. When I did, regarding a vintage clock, they were very responsive (although not very helpful).

[brtn75]

Actually I've contacted Twemco HK office. I've had a first answer. They told me that both the electric circuit board & the gear box needed to be replaced. They offered to give me a quote which they never did. I followed them up by email nearly 10 times but no answer any more...

[Johan de Jong]

Still not sure what exactly happens. Does the motor switch on just once every minute or multiple times? Does it flip all four tiles in one run or does it stop in between? If possible could you make a movie? (with sound)

I also attached a picture I made earlier when I had disassembled it a bit further. On the left you see the motor and gearbox. The brown and black wire power the motor. The two green wires I suspect are coming from a switch in the gears to tell the circuit board when to stop the motor. If you have a potentiometer you could measure what is going on on these wires. It is possible to further disassemble the gearbox but I did not need to do that at that stage so I don't know what exactly is in there.

On second thought: all this analysing might not solve your problem at all but only my curiosity.
If we find that something is wrong in either the gearbox or the circuit board you still need to replace both. And for that you will need Twemco to respond. I like to solve these things myself by tinkering, but you might not be that kind of person

[brtn75]

So, the motor switch multiple times in a row. 4 times exactly. Not even 1s between two switches.
At every switch, 1 tile flips. I’ll try to take a video a to post it within the end of the week.

Thank for your picture. It could be helpful if I decide to go further and try to fix it by myself. But before any attempt, I want to make sure I’m going the right way.

[flipoclock]

Actually I've contacted Twemco HK office. I've had a first answer. They told me that both the electric circuit board & the gear box needed to be replaced. They offered to give me a quote which they never did. I followed them up by email nearly 10 times but no answer any more...

That sucks... I was more lucky in getting a definitive response, although it was 'negative'. I managed to get the parts I needed by getting in touch with the original supplier (label was on the part) and they were still in business and actually willing and able to assist and supply. Not sure if there is a suppliers/makers label on the parts you might need?

Where are you based? Perhaps you could send it to someone here on the forum who might be willing to look at it to see if it is fixable?

[brtn75]

You’re right, if I can identify the faulty component, it could be more successful to contact directly its manufacturer.

I’m based in France/Paris.

[eathan21th]

Still not sure what exactly happens. Does the motor switch on just once every minute or multiple times? Does it flip all four tiles in one run or does it stop in between? If possible could you make a movie? (with sound)

I also attached a picture I made earlier when I had disassembled it a bit further. On the left you see the motor and gearbox. The brown and black wire power the motor. The two green wires I suspect are coming from a switch in the gears to tell the circuit board when to stop the motor. If you have a potentiometer you could measure what is going on on these wires. It is possible to further disassemble the gearbox but I did not need to do that at that stage so I don't know what exactly is in there.

On second thought: all this analysing might not solve your problem at all but only my curiosity.
If we find that something is wrong in either the gearbox or the circuit board you still need to replace both. And for that you will need Twemco to respond. I like to solve these things myself by tinkering, but you might not be that kind of person

Yesterday I got a almost brand new TWEMCO BQ-58. Unfortunately the PCB board inside the clock is totally damaged because of the liquid leakage from the battery.

First I checked the status of the dc motor, it seems it still can work. So my plan is to use Arduino board or NodeMcu board to control the dc motor to make the clock alive again.

I also use the digital multimeter to measure these 2 green lines as the motor is running. As the gear inside the gearbox is in certain position, these 2 green lines will become short circuit. Then I opened the gearbox, I found a magnetic reed switch inside it.

So it could be true, that these 2 green lines are used to provide the signal to the clock controller to stop the motor.

Here is a quick test of the flip clock, driven by NodeMcu board. The further control of the clock will be done later.

[eathan21th]

Actually I've contacted Twemco HK office. I've had a first answer. They told me that both the electric circuit board & the gear box needed to be replaced. They offered to give me a quote which they never did. I followed them up by email nearly 10 times but no answer any more...

I think maybe the magnetic reed switch inside the gearbox is not working correctly. You can try to replace it. Maybe it can help.

[eathan21th]

Yesterday I got a almost brand new TWEMCO BQ-58. Unfortunately the PCB board inside the clock is totally damaged because of the liquid leakage from the battery.

First I checked the status of the dc motor, it seems it still can work. So my plan is to use Arduino board or NodeMcu board to control the dc motor to make the clock alive again.

I also use the digital multimeter to measure these 2 green lines as the motor is running. As the gear inside the gearbox is in certain position, these 2 green lines will become short circuit. Then I opened the gearbox, I found a magnetic reed switch inside it.

So it could be true, that these 2 green lines are used to provide the signal to the clock controller to stop the motor.

Here is a quick test of the flip clock, driven by NodeMcu board. The further control of the clock will be done later.

Here is a quick update. I could use NodeMcu board to control the TWEMCO clock and also monitor the signal from the magnetic reed switch to stop the motor of the clock.

I let it runs overnight, so far the time shown on the clock is still accurate.

Before without monitoring the signal from the magnetic reed switch, the time shown on the clock will become too slow in a very short time.

[eathan21th]

Actually I've contacted Twemco HK office. I've had a first answer. They told me that both the electric circuit board & the gear box needed to be replaced. They offered to give me a quote which they never did. I followed them up by email nearly 10 times but no answer any more...

Although I could control the clock by my own NodeMcu board now. I still want to get a new control board from TWEMCO.
So I sent a mail to them, and after couple days, I got a quotation of the control board from them. And I will try to get one to finish the restoration of the flip clock.

[eathan21th]

Although I could control the clock by my own NodeMcu board now. I still want to get a new control board from TWEMCO.
So I sent a mail to them, and after couple days, I got a quotation of the control board from them. And I will try to get one to finish the restoration of the flip clock.

Here is a quick update. After some discussion with Twemco HK office, I got a new control board along with a new motor and gear box this week.


After taking sometime to install these new parts, my Twemco BQ-58 clock is fully restored and can work with battery now.