Is possible to lengthen the time a wind up clock runs?

# Thread: Is possible to lengthen the time a wind up clock runs?

1. ## Is possible to lengthen the time a wind up clock runs?

I have the mechanical half of a standard electric master clock that came out of a school. The electric movement has long sense quit, so I wanted to turn the mechanical half into an 8 day movement, Instead of an approximately 1 day movement.
Here is a picture of the spring, I think that if I just ordered a longer, or a heavier main spring and balance wheel spring that I could make it become an 8 day clock, however I want to here what people that have been around clocks more than I have. Thanks

2. ## Re: Is possible to lengthen the time a wind up clock runs?

I am not a clock maker, but here is what I think about replacing the mainspring.

The escapement releases one tooth at a time. If the mainspring were stiffer
it would release at the same rate as it does now. It would just waste more
energy as it runs down. To get more time as the spring unwinds the gear ratio
would need to be changed.

A longer mainspring might provide more run time. However, it would need
more space to expand. From the photo it appears to me the space is not
available.

Thanks,
rationaltime

3. ## Re: Is possible to lengthen the time a wind up clock runs?

Thank you for your reply, and now that you explained it that way it makes sense, and unfortunately I do not have access to the machines to make a year to further reduce the ratio. Now I wonder if I make the cylinder that the main spring is wrapped around smaller than there would be more revolutions before the spring ran out. So do you think that would work.

4. ## Re: Is possible to lengthen the time a wind up clock runs?

Sorry, it autocorrected to year, not gear

5. ## Re: Is possible to lengthen the time a wind up clock runs?

I don't know. Could we see a photo showing the spring run down?
A clock maker could probably give you a better answer.

That spring looks expensive to replace.

Thanks,
rationaltime

6. ## Re: Is possible to lengthen the time a wind up clock runs?

I am away from the clock right now, however I would guess the spring to be about 1.5" X roughly 2 ft, I have never straightened it out of actually measure it. It should be all wound down by the time I get home. I will post it then

Thanks
jshields2025

7. ## Re: Is possible to lengthen the time a wind up clock runs?

Well I got a better estimate when I got home, and it has to be between 4 and 6 ft long, and I'm afraid the main spring may have to be replaced, look at the gaps.
Here is another close up of the main spring itself

8. ## Re: Is possible to lengthen the time a wind up clock runs?

And another thing, it seems to be pulsing as it runs, it will seeming randomly speed up really fast and get noisy, then like you flipped a switch it will go back to a page that almost seems a little slow.

9. ## Re: Is possible to lengthen the time a wind up clock runs?

Erratic running may be the result of the mainspring coils catching and releasing rather than sliding smoothly. If you have the electrical components consider restoring them.

10. ## Re: Is possible to lengthen the time a wind up clock runs?

Thank you for your response, sorry I am slow in my response.
I would have enjoyed restoring the electric half, however according to my machine shop teacher when he took it home and tested it the motor just began to get hot and smoke. He is a very mechanical individual and I took him art his word that the motor was junk. I looked into using the motor out of a slave clock, however when I took one out it had completely different numbers on it. I do not believe that they are even close to the same.
After close inspection ous the main spring I see some small gaps in the coils, making me believe that someone may have attempted to remove the main spring without the proper tools. I am going to try just putting a little oil on the spring to try to encourage free movement, however I've also looked into getting a new main spring, and to get the one I believe to be correct it will cost about \$30- \$40, and I am questioning why to invest that into a clock with no face, no case, no real collectable value, and it only runs about a day. I can make a case in the wood shop, and I plan on making a face in the machine shop. However I am starting to wonder if it is worth while for a 24 hour clock.

Sorry if it sounds like I ranted there, I'm really not mad, just beginning to question what I'm doing with this clock. The springs I looked into were labeled as 8 day springs, however when I compared them to what I estimated mine to be, they appeared to be the same.

Page 1 of 2 1 2 Last