h a l f b a k e r yWhere life imitates science.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Please log in.
Before you can vote, you need to register.
Please log in or create an account.
|
Take a round sheet of acrylic, diameter of about a foot. Route out a groove along the outer edge. Create a small indentation in the bottom center, to be placed on a pivot. Take two small, cheap electric clocks and remove their minute and second hands leaving only the hour hands. Mount these on a
base, perhaps a 1' plywood circle, at 12 o'clock and 3 o'clock positions. Mount a vertical bar at the center of the base to act as a pivot for the acrylic. Attach a thin rod to the 12 o'clock position of the acrylic disk and to the end of the hour hand of the 12 o'clock clock, making sure both ends can pivot freely. Repeat with the 3 o'clock clock. Set the 12 o'clock clock to the current time, minus 6 hours. Set the 3 o'clock clock to the current time, plus 3 hours. Place a marble or ball bearing in the groove.
The lowest point of the track will always indicate the current time, and this will be the position of the marble. Artwork and hours can be painted on the acrylic. If a large enough circle, small enough marble, and smooth enough track is used the marble will be constantly rolling.
Illustration
http://www.geocitie...HB/wobbleclock.html
[Worldgineer, Jan 15 2005]
fwiw
http://bz.pair.com/fun/wobclk.jpg
[bristolz, Jan 19 2005]
[link]
|
| |
you are - hmmmm 8 hours behind me. sometimes I think its the other way round... |
|
| |
That gives me an idea. Mount a thin sheet of plastic over the acrylic, with clock numbers painted on. You can now rotate this dial to whatever time zone you'd like. |
|
| |
Sorry, not seeing it. Help me, Mr. Gineer-zard. |
|
| |
[half] It's beyond my artistic abilities to draw this, so words will have to do. Think of two pizza pans, one a few inches over the other but both alined. Now, tilt the top pizza pan a little bit. Keep the centers a few inches apart, but move one edge of the top pan a little lower. Now picture the tilt slowly moving in a circle - the pan isn't twisting, it's just moving such that part is always lower than the rest. That's where the marble will be - slowly rolling around the pan over 12 hours. |
|
| |
If you scale it correctly you can paint each half of the marble a different color and tick off a second with each rotation. |
|
| |
With the whole-room version, you may want to use four clocks and hang strings instead of using rods. Then you can get away with just a track without the disk. |
|
| |
Yeah, got it. I wasn't seeing that the two hour hands would be rotating in planes normal to the base with those two hour hands' planes normal to one another. A mutually perpendicular scenario, I suppose you could say. |
|
| |
The "indentation in the bottom center" was computing as "a notch in the circumference, oriented at the 6 o'clock position" instead of "the center of one face of the disk". |
|
| |
This thing will, essentially, be laying down flat. |
|
| |
Ah, yes. That's the problem with words. |
|
| |
You could have several concentric grooves with a marble in each they would move in formation creating a pointilist sweeping hand (marblist?) |
|
| |
I'll have to take it on faith that [half] understands how this works but I am deeply skeptical as I haven't a clear image at all of how the two clock motors power this thing and if I can't figure it out there is just no way [half] can. Can he? |
|
| |
Also, how do you set the clock motors times (the minus 6 and plus 3 hours settings) if you have removed the hands? How would you know? |
|
| |
For this and other inane commentaries and questions, stay tuned. |
|
| |
<aside> bris, is your reference : Becky the silk and paper *marblist*. Other than that we did our usual bit of snorkeling and eating the extra fattening Lappert's Ice Cream -- damn, that stuff is smooth.
Heh?<aside> |
|
| |
[bris] You remove all but the hour hands. This system has two degrees of freedom. At noon, we want the part near the 12 o'clock clock to be the lowest. That means the hand there should be pointing down. At 6, then, it will be pointing up. At 3, we want the part near the 3 o'clock clock to be pointing down. At 9 it will be pointing up. Let me know if you can't picture the other times. |
|
| |
I also like the many-grooved design. If one or two marbles stick a little you'll still know the correct time. |
|
| |
Ah, the clock faces are perpendicular to the base. You should note in your idea text something like "remove minute and second hands, leaving only the hour hands" for the slower amongst the crowd. |
|
| |
Modification:
After drawing this out I realize the acylic disk might twist around the pivot from even the little forces of the clock hands, making this a 3 degree of freedom system and ruining everything (well not really, but it would be off a little). A little drop of silicone glue at the pivot may fix that, or a rod sticking through the acrylic that will allow up & down motion without allowing twisting. |
|
| |
The track that the ball travels on could be a tube with a bit of colored liquid in it. The liquid would always flow (not get stuck like the ball). Then you could read the time off the tube like a thermometer. |
|
| |
I don't see how the linkage from the ends of the hour hands to the edge of the acrylic sheet could be made. I picture your idea as some kind of crank mechanism, where the hour hand is the crank. But the crank attachment at the end of the acrylic sheet would move the acrylic sheet not only up and down, but around the direction of the clock face.
The arrangement reminds me of the notation used in electrical engineering for rotating vectors, where a rotating vector can be transformed into a sin and cosine wave. So at 12 o'clock the height of the sheet will be a sinusoidal wave 90 degrees out of phase with the 3 o'clock position. |
|
| |
I'm not getting the clock power movement bit of this. Partly because I'm not getting why it's necessary, I suppose. Why not have a single central mechanism that tilts the disk? |
|
| |
I like the bearing in groove that indicates time bit, though. |
|
| |
For safety reasons I need to avoid your birthday party anyway, [half]. |
|
| |
No need for any new excuses. The current collection will do. |
|
| |
But, but, it's a fire hazard. |
|
| |
I've opted for the safer simu-flame candles this year. |
|
| |
But, but, they still use power. Dam diverting amounts in your case. |
|
| |
For some odd reason, when I look at the illustration, I see a big old oyster with a pearl inside. Something's not right with me. I love the name and the idea, however. |
|
| |
35 is not a large number of candles. |
|
| |
Confused, wasn't there an idea here? Or am I at the wrong party? |
|
| |
Candle smoke gives you short term memory loss? |
|
| |
Neat clock, I think I get it. |
|
| |
I wander off to play in the snow, and look what happens. |
|
| |
[Ling] The rods are pinned at both ends, meaning it can rotate freely at both ends. Yes, this will mean a bit of tangential force is applied at certain hours, but the rod(s) that stick(s) through the disk will solve this (see my anno that starts with the word Modification). |
|
| |
[waugs] The reason for the clockwork is because clocks are cheap and easily available. Also, I consider this arrangement mechanically elegant in geometry and coordination of the three clocks. |
|
| |
[bliss] Seeing anything other than the intended concept is an expected and anticipated side effect of viewing a [Worldgineer] illustration. |
|
| |
A facet that I like, about a "Mr. Gineer-zard" illustration. |
|
| |
Build it-- I wanna see pics. |
|
| |
I plan on it. It won't be for a while though - my winter is fairly well booked. |
|
| |
Will it be done by spring? |
|
| |
Oh yes, your visit. I will aim to have it ready by then, but don't promise anything. I tend to have a fairly short baking attention span - my Balloonera prototype is almost completely built and ready for testing, but I have lacked the last hour + balloons + sunny day to follow through completely. |
|
| |
(There was intended a clock-related, double meaning, humor type thing there) |
|
| |
Hasn't this thread wound down yet? |
|
| |
Wound down? I'm alarmed that you would think that. It's not time for that yet. Can't you tell by the look on my face? |
|
| |
I hope you aren't holding your breath for that sunny day thing to happen. |
|
| |
[po], I get that a lot. Interestingly, everyone else uses an abbreviated version of your phrase: "half funny". |
|
| |
It's just that hour conversation has taken minutes off my life. |
|
| |
Don't be dragging out your raggedy, old, second hand puns now. |
|
| |
It's driving me cuckoo trying to think of a good one. |
|
| |
It's no big deal. Don't stress about it. You'll wind up with a nervous tick. |
|
| |
I'd better get some work done now; I'm on the clock, you see. |
|
| |
Yes, they're always watching. |
|
| |
I need to escarp from this. |
|
| |
Hey, [World], [po]'s tocking to you. |
|
| |
[half] Don't interrupt her. I think she's in a groove. |
|
| |
[Steve] So the cam pushes up on the clock face and tilts it in the opposite direction? Not bad. I'm not sure how you'd physically arrange your second idea using cams. |
|
| |
I think you've all lost your marble. |
|
| |
How about replacing the marble with some sort of coloured liquid? That's bound to look good. |
|
| |
*sniffle* I appear to have quartz a cold. |
|
| |
That's better than what I would've suggested (fresh orange juice). |
|
| |
The clock is running on this thread. We annotators have run out of ideas and have to cycle back through the same ideas again. This thread has reached the point of continuous return. If this thread keeps going, "coloured liquid" (or as I spelled it, "colored liquid") will be re-suggested every 4 days. |
|
| |
But how would the minute hand pass the hour hand? |
|
| |
By first signalling and then flooring it. |
|
| |
Then I suppose if they get fast enough, they can pass hundreds of hours per mile. |
|
| |
//If you attach the clocks to the ceiling, you can hang three concentric tracks from a total of 12 clocks.// |
|
| |
I like that. Very elegant - have a clock at each hour. |
|
| |