Instructables
Picture of Lighted Newton's Cradle
OK I'll admit this one is a tricky build. It is all in the alignment and requires quite a bit of patience to get it right. Yes mine is not perfect... Yet!!!

Needs more work on the alignment of the balls!


Step 1: Materials

Picture of Materials
You will need 5 glass marbles about 1 inch in diameter.
1/8 inch brass welding rod.
Pine slats.
fine wire
5 LEDs
A couple of batteries.


You may also want to reference my knife switch instructable. A simple slider will ruin the effect!

Other materials will be presented as the build unfolds...

Step 2: Prepare the marbles

Picture of Prepare the marbles
IMG_4365.JPG
IMG_4366.JPG
IMG_4368.JPG
IMG_4369.JPG
IMG_4370.JPG
IMG_4371.JPG
IMG_4373.JPG
IMG_4374.JPG
IMG_4375.JPG
IMG_4376.JPG
IMG_4377.JPG
IMG_4378.JPG
IMG_4577.JPG
You will need to remove the rounded tip of the LEDs in order to fasten them to the marbles. I used an abrasive cut off tool on a Dremel for this. The resulting surface was hazy and not optically pure. This was not of concern as I will explain in a moment.

The marbles will also need a small patch of roughed up area for contact. Again I used the Dremel and an abrasive wheel to grind a small flat on the surface.

The flat of the LED is glued to the ground spot on the marble using Cyano type super glue. This glue has the added benefit of filling all of the grind marks and making an optically pure connection. The last pic clearly shows the LED on the other side of the marble.
 
Remove these adsRemove these ads by Signing Up
dyly2 years ago
I want to see someone make a newtons cradle that incorporates the curie effect... http://sci-toys.com/scitoys/scitoys/magnets/magnets.html#curie_effect
could you not use conductive thread instead of that wire so as to give it a smother look just a tought
I suppose that you could just as long as you have a good connection at all points.
zappymax2 years ago
1) instead of gluing "flattened" leds on top of the balls, you could drill holes of same diameter (of the leds) into the balls, (need special drill) and then have a stronger adhesion of leds , as the ball would probably broke the flattened - glued surface after "some strokes"... 2) use eventually various color of leds... 3) use colored marbles, (those used by kids years ago) with colored material inside transparent glass. 4) i wonder if the wires from leds could sustain prolonged use, if the material used (aluminum alloy generally) is very fragile and could broke easily.5) leds need generally a resistor between power source and the led, as to produce lumination.
Random_Canadian (author)  zappymax2 years ago
Thank you for your suggestions and I ask that you check out

http://www.instructables.com/id/Old-Tyme-Glass-Lights/

to answer you first point.

yes , drilling glass is not an essay task, if water immersion is used it's a valuable addition. but generally just a water (with or without additive) flow can do the job to cool the stuff (like for hard steel cooling when sawing), The difficult point is a good affordable diamond drill. ... and Just another point, changing from a small to a larger drill bit can broke the glass. very tricky...
digitalia2 years ago
An improvement might be to use the fine steel cable meant for jewelry. It comes in very thin gauges for fine beadwork, and has the benefit of exerting less rotary tension; should make the energy transfer much more efficient.
Random_Canadian (author)  digitalia2 years ago
Thanks. I was looking but locally I have difficulty finding things like that.
pimpdoubt2 years ago
I'm not going to lie, I originally clicked on this to find out what a newton's cradle was, I've always heard it called an executive ball clicker :P
Really awesome project though!
Random_Canadian (author)  pimpdoubt2 years ago
Thanks
455webley2 years ago
really liked the project, being a physics teacher have always been a fan of Newton's cradles....If you would like to increase the cool factor of this project, why not use vasoline glass marbles (available on Ebay from several sources)which contain trace amounts of uranium for color and illuminate them with ultraviolet LEDs.
Random_Canadian (author)  455webley2 years ago
Thanks.

I will definitely keep that idea in the back of my mind for a future build.
zappymax2 years ago
last ... if the leds are completely inserted in a tubular hole, eventually to the center of the balls, illumination would be different,, If leds could be changed for neon lights, and the hole filled with a resin like material to fix the led or neon bulb into the balls, insulation would be obtained with the resin, aso...
zappymax2 years ago
but "sincerely" another kind of "elegant" switch could be found somewhere !!! :-)
even placed on the power source line, the maps are so reduced a mini or micro switch would be enough...
zappymax2 years ago
also... 1) to keep well aligned movements of the balls, the horizontal rods MUST be perfectly parallels and aligned, on 4 perfectly vertical support rods, those shown seems "curved" even on top...2) if the leds are placed in a hole on top of balls, the lighting effect will change, and if the top of the leds is also covered with some mask or paint , it could concentrate "more" light to the sides or bottom of the balls. 3) and trying to perforate completely the balls would create another kind of lightning effect produced on the base, something more "tubular"... or centered instead of rounded ... but the idea is good, and soon a chinese guy will take the idea to mass production...labor costs in the west is too expensive...
jcomtois2 years ago
Great idea. Anything can be jazzed up with LEDs, and this is a good one. Now you need to add a MEMS accelerometer to each one so they change color when they hit!
Awesome idea !!!
Rehmatullah2 years ago
i like your project but why u hang it with wire and both side are current wire......
Brosiman2 years ago
Great project.I'm wondering though if you really need the resistor in this case.The batteries will have less than 3 Volt in them and would the brass bar not act as some kind of resistor ?
Random_Canadian (author)  Brosiman2 years ago
The resistor is there to limit the current. Ful battery power is not needed and this will extend battery life...
skiedra2 years ago
This looks really cool!
Awesome idea. They look great!
omnibot2 years ago
I love the knifeswitch!
mikeasaurus2 years ago
Looks so great when it's lit up!