In this instructable we'll convert an inexpensive clock into wall art with a subtly changing moire effect. I'm expecting the MoMA to call any second.

In this video the effect has been sped up for clarity, however the same effect could be had with a high torque clockworks using the minute and second hand. I enjoy the subtle effect of using the hour and minute hands myself. Not sure what youtube did to the color in my video.

A moire pattern is caused by interference, more information is available here moire at wikipedia

Step 1: Gather your materials

You will need

A clock movement
Photo paper
printer transparencies
thin cardboard
super glue
assorted odds and ends

Start by removing your clock movement from a clock. Place your thumb against the time setting knob and gently twist off the hands, then unscrew the nut around the shaft, the movement should now be free. be sure to save the hands.

Step 2: Creating the moire pattern

There is a great deal of math available on the net about moire patterns, however, since it is spring break, we will forgo it. A moire pattern can be any pattern that causes an interference effect, for instance here's a moire pattern caused by the office walls where I work. Using a graphics program make any pattern you like, circles, grids, radial lines. I used radial wedges. Contrasting colors are nice too.

Step 3: Making the dials

In this step we take our two patterns and print them out. One needs to be printed on photopaper and the other onto a transparency.

Once printed the photo paper dial will need to be reinforced by gluing, with aerosol glue, to a piece of thin cardboard.

Step 4: Mounting the dials

At this point we'll trim the dials down to circles, the only other change we need make to the transparent dial is the addition of the minute hand, with the hand removed, to the center, attach it with super glue. Do NOT use a super glue accelerator on the transparency, the ink will run.

The photo paper dial is slightly different. For a proper moire effect we need not just rotation, but translation, so the hole will be off center. The easiest way to locate the hole is to overlay the transparency until you get the effect you like, the center of the transparency is now located where you will make the hole in the photo paper.

Once you have the hole in the photo paper dial, super glue on the hour hand and balance the dial, our little clock does not have enough torque to lift the off-balance dial. Here I used a pair of bottle caps with double sided tape. Balancing was accomplished by spinning on a pencil tip and balancing until it showed no preference in stopping.

Step 5: Final assembly

Simply push the dials back onto the clock movement, make sure they're square and neither dial binds. Hang on the wall, and enjoy.

just don't forget the batteries
I made one using an Room Essentials Style clock from target that cost \$3.99, and just glued the one to the backboard over the clock, and had the transparency on the second hand. I was able to keep the frame and didn't need counter weights. HOWEVER, the small motor was unable to move the transparency attached to the second hand.
Jizzed in my pants when I understood how simple mechanically is that. Love it. How big are your circles? wondering how big I might get.
How big can you print? but really you're limited by the torque of the clock motor, those are about 6 inch circles.<br><br>PS go change your pants.
Pants?
No thanks, already have some.<br><br>it was a bon mot based on your comment about your pants.<br>
I'm such a retard, I forgot I wrote it xD
thats a divers weight ?
Yep, but I haven't dived in 25 years.
How did you make the patterns for the dials?
I just created a pattern of colored radial segments in gimp 9I think) and printed to a transparency.
I'm having a lot of trouble doing the same in Gimp. Could you please(!) upload the original GIMP files you used? When I print these they are all pixelated, plus I'm afraid its going to print both the blue and white radial segments onto the transparency paper. <br><br>Thanks!
Those are the original files, click on the little boxed i in the upper left hand corner, DL the large 3200 x 3200 originals.
Awesome, thanks so much
I just copied the images.
They did something similar to this in Star Trek TOS, using clockwork motors and whatnot to make moire patterns on computer displays and even the little disc on the communicators... :)<br> <br> Pretty cool work... :)<br>
Wow, great idea! I just dropped a cheap (actually it came as a free kit with something my wife bought) clock and I lost one of the hands. The little black clock-box is sitting in front of me right now looking for something exciting to do...I think we've found it right here! Thanks!
hahaha... yeah, i'm in a similar position. i was cleaning out my pantry today and found some free clock that came from some insurance company. so, i was one step from tossing it until i thought "hmmm... maybe i can do something with this. talk about kismet.
Sweetness! You are no longer on my annoying list. Just kidding, you've always been awesome. Keep up the great work! +5/5 stars.
Nice job! 5 stars!
Can you leave the hand intact and have clock and wall art at the same time?
Indeed you could, you could also make one of the lines on each dial black to serve as hands. I've also thought of a way to make the moire pattern act as virtual hands, but that will probably have to wait until summer break.
Using the interference pattern, you could also use the minute hand to create a virtual seconds hand. In fact, if you made a sufficiently accurate background and mask, you could create a display that ran on the hour hand and showed hour, minute, and second. Keeping it as visually stimulating as the original would require more effort, though.
I want this! Looks pretty easy, even, though I have no idea how to generate the lines necessary.<br/>Anyone interested, check this page out: <a rel="nofollow" href="http://switzernet.com/people/emin-gabrielyan/070306-optical-speedup/">http://switzernet.com/people/emin-gabrielyan/070306-optical-speedup/</a><br/><br/>figure 18 shows a moire effect where a slow-turning wheel generates &quot;virtual hands&quot;, with a multiplier of 30x the speed of the slow wheel. So, just using a multiplier of 60x on a minute wheel would create virtual second hands. <br/><br/>The math looks pretty easy. Perhaps I will waste some time figuring out how to make a clock with virtual hands.<br/><br/>This effect: <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Shape_moir%C3%A9">http://en.wikipedia.org/wiki/Shape_moir%C3%A9</a> <br/>is even neater. I wonder if it could be used in some way to make a digital moire clock.<br/>
Help needed from other Star Trek geeks: This was on the original series as one of the monitor displays on either Spock's station or Urhura's. Tell me which one before I go insane!
Spock's (who else could make sense of it?). Sweet Instructable man.
...but having a purely aesthetic display that serves no function would be.... highly illogical!
Turns out I was wrong, I checked recently and Urhura's display is similar.
Couldn't you put a giant black arrow on each one and have it still tell time?
I'm going to make one with hexagons. I was looking through two hexagon mesh walls of a bus stop once, and it made big hexagons where they overlapped.
I think you could just hot glue the cardboard to the movement and then have the transparency directly centered in the minute hand. you would get the same visual effect. O and I'm wondering if I can cut up one of my old 3-ring binder plastic dividers instead of buying transparency paper...
hmmm i wonder what would happen if u put 1 on all of the dials. if the clock had a smooth moving second hand???
Dude I'm gonna have mine w/me @ all times. I'm gonna try to make a watch hack.
Excellent. Got massive headache now from mine, having tha spiral on a smooth running second hand is Funky!!! Now wheres my advil! :)
it's cool ,so gooddddd.
Awesome job! This looks really cool and I think I'll do this sometime.
I used to build similar devices that would sit on top of overhead projectors and would display 30 foot interference patterns on bands.
If broadcasters are wearing a plaid (or similar pattern)tie, the tie creates a "moire" pattern. Or maybe that's the inaccuracies of RF TV. Who know. Except now I know what that pattern's called. Awesome.
Yes, That's a moire pattern. It's created by the tie pattern crossing over with the scan lines of the television.
Sweet. Thanks for the info. So, it only happens when the tie has diagonal lines?
It's more obvious with diagonal lines since the trace lines are horizontal. You see it occur in a pin-stripe suit as the lines go diagonal.
Cool thing! ;) I will make one. :)
Consider the following:<br/><br/><ul class="curly"><li>Make the static clock face an offset radial pattern</li><li>Make the hour hand a transparent linear moire pattern (just parallel lines)</li><li>Make the minute hand a transparent centered radial pattern</li><br/></ul>This way you wouldn't need to balance the rotating patterns and would get a bit more complicated pattern.<br/>
Well done instructable! I had a beer sign/clock once which used this concept. I could sit and drink and watch it for hours. Thanks for sharing.
Psychedelic!
It's working now. It's also pretty cool.
YouTube says your video is private. I'm waiting with bated breath to see it!
Fixed, I think ;-)
Yup. I saw it- nice!