I've added video of the clock. I will be working on carving out windows in the face of the clock. I will upload pictures and/or a video of that when I am done.
I've been into woodworking for a few years now. I love the idea of being able to make things that I can use. A few years ago I came across a clock that was made out of wood. The face, arms, frame, and gears were all wood. It really impressed me, and I kept it in mind for a future project.
I've decided to take on the wooden clock in this Instructable, and hopefully share what I have learned to help others with similar interests.
One of my goals with this was to use common tools that are more widely available to most people. I didn't use any expensive hard to find wood working machines, or costly software packages when designing this. The software used is either open source, or free, and the machines used are some of the common ones that most woodworkers would have.
I've been into woodworking for a few years now. I love the idea of being able to make things that I can use. A few years ago I came across a clock that was made out of wood. The face, arms, frame, and gears were all wood. It really impressed me, and I kept it in mind for a future project.
I've decided to take on the wooden clock in this Instructable, and hopefully share what I have learned to help others with similar interests.
One of my goals with this was to use common tools that are more widely available to most people. I didn't use any expensive hard to find wood working machines, or costly software packages when designing this. The software used is either open source, or free, and the machines used are some of the common ones that most woodworkers would have.
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Signing UpStep 1: What You Will Need
Here is a list of things you will need
For Designing:
OpenOffice Calc - For calculating the Gear ratios
free2Design - For designing the gears
Gimp- Modifying and editing images
Blender - For rough modeling gears to make sure there aren't any interferences between gears and axles.
*note - You probably can use Blender to do all the designing, but my Blender skills aren't up to speed. It was easier to draw them dimensionally accurate in a 2D package and import that into blender.
For Woodworking:
Scroll Saw
Drill Press
Miter Saw (Table or Band saw will also work)
Hand Saw
Clamps
Spray Adhesive (3M Super77)
For Designing:
OpenOffice Calc - For calculating the Gear ratios
free2Design - For designing the gears
Gimp- Modifying and editing images
Blender - For rough modeling gears to make sure there aren't any interferences between gears and axles.
*note - You probably can use Blender to do all the designing, but my Blender skills aren't up to speed. It was easier to draw them dimensionally accurate in a 2D package and import that into blender.
For Woodworking:
Scroll Saw
Drill Press
Miter Saw (Table or Band saw will also work)
Hand Saw
Clamps
Spray Adhesive (3M Super77)
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Please reread the teachings of Galileo Galilei. It's Physics 101.
Since Galileo discovered the isochronic property of the pendulum, they have been the world's most accurate timekeeping technology until the 1930s. This could NOT be so if the angle of the swing would vary the frequency.
Wider swings do NOT take longer, unless you are comparing a swing of 1 degree v. 179 degrees. Then, the variation in period or frequency is really influenced more by friction in the bearing and air friction.
Clocks, use relatively low angle pendulum swings, so these factors are kept at a minimum as there is less movement. The only reason a clock's pendulum may have a higher mass, is to take advantage of Newton's First Law of Motion to overcome as much of the friction to keep it moving as long as posible. The addition, or subtraction of mass will NOT change the frequency of the pendulum.
The period of swing of a simple gravity pendulum depends on its length, the local strength of gravity, and to a small extent on the maximum angle that the pendulum swings away from vertical, called the amplitude.
It is independent of the mass of the bob.
If the amplitude is limited to small swings, the period T of a simple pendulum, the time taken for a complete cycle, is a function of the length of the pendulum and gravity.
For small swings, the period of swing is approximately the same for different size swings: that is, the period is independent of amplitude.
This property, called isochronism, is the reason pendulums are so useful for timekeeping.
Successive swings of the pendulum, even if changing in amplitude, take the same amount of time.
The advent of the anchor (recoil) escapement effectively solved the problem by massively reducing the required arc of the pendulum thereby making the discrepancy so small, it could be ignored, certainly in domestic clocks. There is still an error however, and to reduce this as much as possible the best quality clocks used by astronomers were designed to have the smallest arc of movement they could get away with. You, in your response also quote that the amplitude of the pendulum must not be large, so I'm not certain why you thought rennysonceman was incorrect?
Similarly, in theory the mass of the pendulum bob is unimportant, but in practice, it is desirable to make it as heavy as possible, but with the smallest surface area possible in order to minimise the effects of air pressure and friction. The smallest surface area would be provided by a sphere; horologists compromise and use a cylinder because it is easier to make. The disc shaped bob invariably found on domestic clocks might seem desirable to reduce air resistance but apparently confers no great advantage.
Sorry, I've drivelled on too much.
http://en.wikipedia.org/wiki/Christiaan_Huygens
For small swings, the effect is quite small and could be ignored in a weight driven clock, whose pendulum swings are reasonably constant and therefore unvarying. For spring driven clocks, where the swing gets smaller and smaller as the spring unwinds, the effect was bad enough that a fusee was added to the finest movements to keep the driving force, and therefore pendulum swing, as constant as possible. Cheaper spring driven clocks weren't very accurate anyway, and the recoil escapement used in those movements tended to drive the pendulum faster when wound tight, which partially compensated for the wider (slower) swings of the pendulum. Not that it really mattered in that era, as people set their clocks daily anyway, to a sundial or the town clock bell.....
Cheers,
Chris
there should be more people with this opinion here!
this is very nice! well done.
The free2Desing program didn't have an export function. I also didn't realize it wouldn't be around for much longer after I used the program. They shortly canceled the project. The reason I used it was that I was looking for a free, easy to use program, that had certain functions that made designing the gears easy.
My main purpose of this Instructable wasn't to make something that everyone could duplicate(you could, but honestly it's an ugly design). It was to teach anyone interested in building a clock, how to figure out their own design. Yes you can buy plans, kits, and other clocks to make, but putting it together doesn't teach why you need certain ratios. It just teaches you how to assemble something.
I hope to make another clock sometime, and if I do, I will make sure it's in a program that most everyone can use.
Thanks for viewing this Instructable and all the comments.
Nice instructable.
"The frequency of the pendulum is dependent on the length of the string or wire. The shorter the wire, the greater the frequency or how fast it goes back and forth.
The frequency is independent of the amplitude of the swing, provided the initial angle is not large. At larger angles, there is a slight change in the frequency.
Also, the frequency is independent of the mass of the bob. In other words a pendulum with a heavy bob will move at the same rate as one with a lighter weight bob. But this only makes sense, since the acceleration of gravity on a falling object is independent of the mass of the object."
See:
http://www.school-for-champions.com/science/pendulum.htm
I just become a member. And it's very cheap but :
I cannot open any of your files.
Your ods file is not recognised by my Open Office Calc and free2design is not found by my explorer.
Then could you please say me what I'm doing wrong ?
Thank you for your quick answer.
Best to all.
Ed
Or join their beta program and get their beta software.
http://www.a9tech.com/a9cad/
Unfortunately, it does lack certain advanced features that would make your design work a lot faster.
For example, in the case of designing these gears, it would be handy to have a "Polar Array" feature. That's where you select an object or group of objects, Pick a center point, tell the program how many duplicates you want and how many degrees you want it to cover. The program would then automatically rotate and place the objects for you. So, you could draw one tooth of the gear, tell the program how many teeth you need and where the center of the circle is and it would draw the whole gear for you.
Alas, with A9CAD, you would have to draw each tooth individually. :(
Still, it is free and it is effective. I was trained on AutoCAD at work, but couldn't afford a license for home. A9CAD is a good free substitute.
In Step 4, there is a spreadsheet with each gear,
the number of teeth, and the ratio that the gear train creates.
But for a quick reference,
here are the Gears and their teeth:
Each line represents an axle
Pinion 1 - 12 teeth Wheel 1 - 36 teeth ,
Pinion 2 - 10 teeth Wheel 2 - 40 teeth,
Pinion 3 - 8 teeth Wheel 3 - 40 teeth,
Pinion 4 - 12 teeth Wheel 4 - 40 teeth,
Pinion 5 10 teeth Wheel 5 - 36 teeth.
The escapement gear has 30 teeth and is not in the list above since it does not factor into the calculation of the gear ratios.
I like this & trying to make one
wish i could open the files
or that jpg files cound be downloaded
I am extremely amazed!
I hope i would have time to try this out.
Thanks Marvay. Great work!
- Jack -
Thx
Art
all the plans on it are free and somewhat easy to follow
http://woodgears.ca/gear_cutting/template.html
http://www.brassgoggles.co.uk/bg-forum/index.php?topic=8006.msg146566#msg146566
On the upside, I did find this site for designing gears:
http://woodgears.ca/gear_cutting/template.html
You'll need to scale them as necessary because they are in an arbitrary unit, but that shouldn't be too difficult with any other cad software or even something like Illustrator if you print it to a PDF (I can't remember Illustrator's open source equivalent).
http://www.slipperybrick.com/2008/01/seiko-discus-watch/
Other than that, remember that there are many other interesting gear styles and escapements depending on what style your into. Here's a site with some interesting thoughts on gear design and here's one with great information on many different types of escapements. BTW your escapement appears to be a variation on the swiss lever design.
All in all, a very good and informative instructable. +1 and faved!
It reminded me of a 3D-printed clock I was working on a long time ago. I just posted a Slideshow here: 3D-Printed Clock and Gears.