What can I make to keep track of time without electricity

In summary, the person is looking for an accurate time keeping device that does not require electricity. They are considering a variety of options, including a wall clock, a sun clock, a Roman water clock, and a sand clock. A traditional watch that can be wound up is the most accurate, but the more expensive they are. A Newton's cradle would be less accurate than a single pendulum, but a pendulum without friction would be accurate.
  • #1
Michael2525
22
1
I need to make a time keeping apparatus that doesn't require electricity. It needs to be something I can make at home and can obtain the resources from a local department store(menards or Home Depot etc.). Any suggestions?
 
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  • #2
Michael2525 said:
I need to make a time keeping apparatus that doesn't require electricity. It needs to be something I can make at home and can obtain the resources from a local department store(menards or Home Depot etc.). Any suggestions?
sun clock, Roman water clock or sand clock, Foucault's pendulum
 
  • #3
fresh_42 said:
sun clock, Roman water clock or sand clock
Those clocks are not accurate enough, I need something that can be measured to at least the nearest half second, tenth second preferably.
 
  • #4
Michael2525 said:
Those clocks are not accurate enough, I need something that can be measured to at least the nearest half second, tenth second preferably.
So you need a traditional watch that can be wound up. The more accurate the more expensive they are.
A wall clock would give you the half second.
 
  • #5
fresh_42 said:
So you need a traditional watch that can be wound up. The more accurate the more expensive they are.
A wall clock would give you the half second.
Except it has to be handmade. Do you think an oscillating spring or a Newton cradle would work?
 
  • #6
Michael2525 said:
hose clocks are not accurate enough, I need something that can be measured to at least the nearest half second, tenth second preferably.

That's precision, not accuracy. Accuracy is "loses or gains less than a second per year".
 
  • #7
Michael2525 said:
Except it has to be handmade. Do you think an oscillating spring or a Newton cradle would work?
For a while. You can't compensate friction.
 
  • #8
Actually, if I had a pendulum attached to something with little friction, wouldn't that work?

It only needs to run for six minutes
 
  • #9
Michael2525 said:
Actually, if I had a pendulum attached to something with little friction, wouldn't that work?
I'd try Newton's cradle.
 
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  • #10
fresh_42 said:
I'd try Newton's cradle. There you can adjust the frequency.
Do you know any special materials that would reduce friction? Would oil help?
 
  • #11
Michael2525 said:
Do you know any special materials that would reduce friction? Would oil help?
It is the air and the bumps that reduces energy. With 2 or 3 heavy metal balls you probably have the least loss.
 
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  • #13
Michael2525 said:
if I had a pendulum attached to something with little friction, wouldn't that work?

A) How will you mechanically count swings?
B) How will you get the sub-second precision you say you need?
 
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  • #14
Michael2525 said:
Actually, if I had a pendulum attached to something with little friction, wouldn't that work?
It only needs to run for six minutes

Vanadium 50 said:
A) How will you mechanically count swings?
B) How will you get the sub-second precision you say you need?

exactly, a clock would still be needed to time the swings
you are not going to build something with the accuracy you need that is non-electronic from things at home
So why does it have to be non-electronic ?
 
  • #15
Michael2525 said:
Those clocks are not accurate enough, I need something that can be measured to at least the nearest half second, tenth second preferably.
Dripping water, fed from a reservoir that is kept full to the brim and overflowing so its timing doesn't "run down". A few drops per second should be manageable.
 
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  • #16
Michael2525 said:
Those clocks are not accurate enough, I need something that can be measured to at least the nearest half second, tenth second preferably.

It's not clear what you mean. Do you mean "can be measured" or "can be used to measure" ?

If you are trying to build something that can measure something to a tenth of a second then it may help to tell us what exactly it is you are trying to measure?
 
  • #17
Michael2525 said:
Except it has to be handmade

Some clock-making schools required their students to make a clock or watch from scratch starting from a block of brass as their final exam. So, yes you can make a top quality mechanical clock at home. You just need a lot of skills and practice.
 
  • #18
anorlunda said:
Some clock-making schools required their students to make a clock or watch from scratch starting from a block of brass as their final exam. So, yes you can make a top quality mechanical clock at home. You just need a lot of skills and practice.
They can be made even from wood. However, to achieve a measurement of .1 s one needs a lot of skills and really many toothed wheels. Tough job to be done at school. I bet that even Swiss schools never would require such a work to be done by students.
 
  • #19
fresh_42 said:
I'd try Newton's cradle.
Newton's cradle would be less accurate than a single pendulum because of the losses during those collisions and the spread of time periods between the individual pendulums.
A free swinging pendulum without an energy source can be very accurate but, as with real clocks, the pendulum needs to get energy to stop it running down. Foucault's Pendulum would go for, say 24 hours if you could have access to a stair well or very high ceiling (10m+) and a good knife edge mounting to hang it from. Six months running time is a tall order unless you are a pretty good machinst and can make yourself what would be effectively of fully working pendulum clock. Counting the swings involves taking energy from the system unless you use an elecrical detection system.
Let's face it, this is a very tall order. They had enough trouble making accurate clocks when they had access to highly skilled craftsmen and decades of experience.
A good non-electronic time reference, not reliant upon very good mechanisms is Astronomical observations (say the orbits of the moons of Jupiter) that was a serious condender in the quest for Longitude measurements by navigators. But you can't buy a good enough telescope from a hardware store. A solar clock (armillary sun dial) can give accuracy of less than a minute if there is a clear view of the Sun and the shadow has a long throw. The shadow moves at half the rate of a clock hour hand and can be calibrated with a regular clock. It's time varies a bit over the year because of the Earth's Orbit but that's easy to calibrate out that variation. You just need to set it up correctly. You need to live somewhere sunny, for reliability. You could, perhaps, make yourself a Backstaff, which was the forerunner of the Sextant. With that, you could make astronomical observations to get the time from stars, the Moon or the Sun.
Why not go back and ask 'them' to set realistic targets for this project or call their bluff and ask how 'they' would do it.
 
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  • #20
NascentOxygen said:
Dripping water, fed from a reservoir that is kept full to the brim and overflowing so its timing doesn't "run down". A few drops per second should be manageable.
Add dye to the water, then to perform the timing you could have someone (or a mechanism) swiftly draw a ribbon of white paper through the stream to record each drip as an individual coloured spot on the ribbon.
 
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  • #21
Is it possible to have a pendulum that has a single pivot point. So instead of the pivot be a rod, it would be something like a needle on a metal piece that turns. Check below for a sketch.
 
  • #22
image.jpg
 
  • #23
Looks like a metronome.
 
  • #24
NascentOxygen said:
Add dye to the water, then to perform the timing you could have someone (or a mechanism) swiftly draw a ribbon of white paper through the stream to record each drip as an individual coloured spot on the ribbon.
Yes - a water clock would be a possibility. You wouldn't need to count the drops - just see the rise in level of the receiver. Evaporation would be a possible problem, so the system would beed to be enclosed and a bit of washing up liquid in the (very clean and grease free) receiver could keep the meniscus steady. Water clocks were fairly common at one time (before the arrival of the escapement / pendulum clock).
Basically, we are stuck with a compromise between running time and timing accuracy. Counting big numbers accurately is very hard if all you have available is hardware store materials. A bucket would last you a long time and a measuring jug would have finer divisions on it but get filled up quicker.
 
  • #25
I need something that can be measured to at least the nearest half second, tenth second preferably

Whatever clock you build best have a think how you are going to measure it's accuracy. Perhaps have the pendulum or water drops interrupt a beam of light?
 
  • #26
NascentOxygen said:
Add dye to the water, then to perform the timing you could have someone (or a mechanism) swiftly draw a ribbon of white paper through the stream to record each drip as an individual coloured spot on the ribbon.

Very clever. I like it.
 
  • #27
Right now I am leaning towards a pendulum, but what can I do to make it very consistent? I considered an escapement wheel so that a) it makes counting by seconds easier and b) it will give the pendulum a little push. However, the precision that takes is too much. Unless someone can find an escapement that is easier to make than a deadbeat escapement.
 
  • #28
fresh_42 said:
sun clock, Roman water clock or sand clock, Foucault's pendulum
I want to go back to the Foucault pendulum idea. What are ways I can maximize its run time without giving it an extra push?
 
  • #29
Michael2525 said:
I want to go back to the Foucault pendulum idea. What are ways I can maximize its run time without giving it an extra push?

Read again post #19:

sophiecentaur said:
Foucault's Pendulum would go for, say 24 hours if you could have access to a stair well or very high ceiling (10m+) and a good knife edge mounting to hang it from.
The difficulty is its length. To measure seconds you would need a precise scale on the floor. And still no way to count. Foucault's pendulum is normally used to demonstrate the Earth's rotation, i.e. 24h. You can surround it by domino stones that fall when the pendulum arrives so you have a sort of measurement. But far from being in the range of seconds.

The task itself is rather difficult. Captains have struggled a long time to get hold of a precise time measurement. It's an interesting part of history.
Maybe the best advice is really to call the bluff. Or forget about your desired precision.
 
  • #30
fresh_42 said:
Maybe the best advice is really to call the bluff. Or forget about your desired precision.

wise adviceas a number of us have said, even if you use some sort of pendulum system, you still need a way to time it
and this is still going to involve using an accurate clock, be that mechanical or electronic
 
  • #31
sophiecentaur said:
Why not go back and ask 'them' to set realistic targets for this project or call their bluff and ask how 'they' would do it.
Agreed. I'll be more direct: Michael, what is the purpose of this project? Why are you undertaking it? Knowing that might help people understand your constraints and be able to provide more/better assistance.
 
  • #32
I just want to make something like a stopwatch that can accurately measure time within a certain interval of time
 
  • #33
Would this work?
 
  • #34
Michael2525 said:
I just want to make something like a stopwatch that can accurately measure time within a certain interval of time
Thanks. "Certain interval"? Is your "accuracy" constraint based on something or just randomly selected? And do you need precision or accuracy or both?
 
  • #35
Michael2525 said:
Would this work?

That's just an odd and mediocre pendulum. I don't think it would be useful for this project.
 
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