This might be ho-hum, old news for many, but on the off chance that it’s new to others here goes nuthin’.
Have you ever wanted an led that doesn’t exist in size or shape? Bigger? Sphere or cube? Abstract? I have. Here’s a couple vids to demonstrate the concept, you’ll need thermoplastic beads, and your imagination. I’m using (any clear bodied LED works, diffused ones not so much) a ‘highbrightness’ 5mm, 7 color flasher LED driven with a 555 circuit.( you can find one that works on youtube). Soften 8-10 pellets into a blob in hot water. Use a spoon to lift the blob out of the water (blow on it and let it cool a few seconds) and carefully mold them around the LED so that the ‘shell’ will slide off when it cools. Now soften 50-100 pellets and shape them as desired, mash the ‘shell’ into the new shape ( be carefull not to mash the shell, as it will soften in the hot material) and re-shape as needed. Now stick whatever you’ve created on the LED and plug it in.
This might be ho-hum, old news for many, but on the off chance that it’s new to others here goes nuthin’.
Not ho hum at all! This is a great share, @waxmoose! I heard that milk jugs are thermoplastic - not sure what the recycling number is… Is that an option for folks who don’t have thermoplastic beads?
The more I thought about it, I realized I’ve got translucent plastic stuff around the house like food containers, measuring cups, even found a spatula with a translucent silicon blade, or take a clear plastic bottle and rough it up with sandpaper.
If the beads are hard to find, something better if less durable that I know is widely available Sculpey translucent modeling clay. I haven’t done more than make 2 un-baked marble size test peices, but the early results seem very promising, and that stuff is everywhere for about $2-$2.50 a 1.7 oz bar. Also easier to work with than hot plastic for sure!
Agreed with @JackANDJude - definitely not ho hum… Excellent work!
I’m currently working on a project which requires a single, wide-angle LED - the standard narrow-beam LED on the “Long LED” module will not do and the LED on the “Bright LED” module is set too close to the chip thus the magnetic connects impair the light to the sides. While I like your thermoplastic beads idea, the light needs to be bring, not diffused. So, I am looking for options… I asked tech support and the standard LED on the “Long LED” module cannot be swapped for a wide-angle LED. Now I am wondering how I can add my own wide-angle LED to a LittleBit and you seem to have done that - although your rig here looks more complicated than my skill level will allow for. Any ideas for adding my own two-prong LED to a LittleBit module? Perhaps the Proto or Perf modules could help?
Thanks anyone who has any ideas!
The Long LED is attached to the Bit’s board by means of a removable connector. You should be able to put the LED you want on a stalk and attach it to that connector. I have one question - is the resistor in the stalk, or is it on the board. Stalk would be best (most flexible.)
@straylight6, Ha! My skill level wasn’t up to it either when I started on that thing! I ruined the first try when it was finished by jamming meter probes into the Bitfeet which bent the pins, and I can’t quote myself when I broke the second perf board halfway through ( more hours but I salvaged the Bitfeet cuz I knew not to jam probes in them), so it took me and my skill level 3 trys to get that rig built, but now my skill level knows how to do it. I’m not telling anybody how I fried my motorBit AND my RGB LEDBit. Now lemme ask about your project.
So anyway, this wide angle LED, do you need to see it from all angles, or does it need to light up a wide area or hit multiple sensors or what?.
@chris101 Oh, I hadn’t even considered the location of the resistor, but I’ll guess you are correct that there would need to be one in the stalk given that the LittleBits power source is a 9V. So, you’re suggesting to remove the default stalk, rewire the connector to my own wires, LED and appropriate resistor for the voltage of my wide-angle LED? Hmm, I like this, but I’m an electronics beginner (like, proto-beginner - which is why I like the pre-built LittleBits stuff so much! ). However, excellent to know there is a straight-forward solution for this in needed. Thank you very much for your reply and this idea - I’ll let you know if I give it a go in the end!
@waxmoose Thanks for this, and being candid about your trials along the way. I certainly say you’re skilled now - I wouldn’t even know where to begin on what you’ve created above. Excellent!
Thanks also for asking about my project. I am trying to make a mini planetarium for my daughter. It’s just a simple light inside a dome with holes poked in it which turns. I have everything sweetly worked out with LittleBits except for the light source. It must a be a single, bright light - multiple lights create multiple beams through each hole in the dome as well as fuzzy projected stars from refraction. Also, standard LEDs have a pretty focused beam which means only the portion of the dome the LED is aimed at gets light. Thus, I would prefer to use on of these: http://shop.evilmadscientist.com/productsmenu/partsmenu/354 (White 8 mm Clear Lens Straw Hat LED) which has a 110-degree beam angle and is super bright. Problem is, I don’t know how to power this via LittleBits. @chris101 has a nice solution above but finding the right capacitor and wiring up the connector back to the LittleBit “Long LED” module may be beyond me so I’m looking for simpler options if anyone can think of any.
Also, before the suggestion is made for using a light which is not connected to LittleBits, know that I have incorporated a timeout of the turning and the light source so it all shuts off after so-many minutes (ie. after she has fallen asleep) - that’s why I want all of this connected to the same power source.
Anyway, thank you for replying to my post, your kind works about skills, your interest and, also, any thoughts you might have going forward - I appreciate it!!
Hiya Straylight (@straylight6),
There are only two resistors on the Long LED Bit, according to this schematic. There are two resistors on the circuit board (also an op-amp.) You can see how the circuit is constructed here. However I still wanted to be sure some electronics were not hiding in the bulges of the LED stalk, so I did a careful (and reversible!) dissection of the business end of the stalk:
So, the current limiting 1000 ohm resistor is on the Bit’s circuit board and not in the stalk. To make a new stalk, you would need two lengths of stiff, single strand, insulated wire, two sizes of heat shrink tubing, a suitable LED (the wide angle one you found at from Evil Mad Scientist looks great), and a specialized connector. You will need to find the exact one, as it has tongues and grooves that must align for it to work:
I plan on going to Fry’s electronics after next payday and trying to find the parts to make my own Long LED stalks in a variety of wavelengths. I’ll post again once I’ve done it.
NOTE: No bits were harmed beyond easy repair in the making of this post.
What!?! @chris101 - you, my friend, are incredible! Thank you so much for going to all of this trouble and investigation! Amazing! So, your comment earlier about the resistor has prompted me to read up as not to sound like a total electronics fool, and now the problem is that I am like the white belt who reckons they know enough karate to head to the dodgy end of town and clean up house - which is where I am going to get into trouble. But here goes.
First, I found a brighter LED capable of 30-35 Lumens so this object (http://lighthouseleds.com/8mm-straw-hat-wide-angle-5w-led-cool-white.html) will be the basis of my math. It has a forward voltage of 3.2-3.6V and the current is listed on the page as 120mA or .12A. Naturally, the LittleBits circuit is powered by the 9V power bit so quick resistance calculation (using V1 = 9, V2 = 3.6 and I = .12) says I need a 45 ohm resistor to go with this battery and this LED. But now, two (white belt) questions emerge, do I need to care about the Power of the resistor? Squaring my 5.4V difference and using my 45 ohm resistance, it looks like I need a 45 ohm resistor which can dissipate 648mW or round up to 1W.
Second, your latest comment about there being a 1000 ohm resistor on the board itself makes me think I am not taking into account nearly enough. Now I am thinking I need to recalculate all of this based on the voltage which is leaving the board into the stalk for more accurate values…
Am I doing too much? I am into cutting the stalk, adding the LED above (as well as an appropriate resistor) and heat shrinking it all back together, but not sure how to proceed to know the exact resistor I need to assure I’m not going to fry the LED.
Thanks again for all of your effort and thoughts - the images are extremely helpful!!!
@straylight6 Although there is a 9V battery, you’ll need to recalculate your required resistor as littleBits is a 5V system. The blue power module is a power regulator.
As to where the two resistors go (plus some other helpful info), check out this hardware thread: 1.1 Make: It’s New To You
That thread is a treasure trove for Bit-hackers!
I am intrigued by your planetarium idea. It, sounds really cool, but seems like a single LED will lose a lot of it’s light where it doesn’t go through a star hole. I wonder if using several LEDs, each hitting a small group of stars, would be brighter.
Also the strawhat LED draws about 50 times more current than does the original Long LED. The usb power (p3) would probably have enough (milli)amps though.
So maybe 5 or 10 regular ~30mcd or so LEDs would give more light through the holes, than even the 5W high power LED by itself. I’d start with a 300 ohm resistor (per LED), and change it up or down depending on the current draw and brightness. You probably don’t want any single LED to draw much more than about 20 milliamps, and I think the limit on a littleBit is 250ma total.
Oh! 5V system?!? Wow, so much to learn! Thanks for that info and the hardware thread link @JackANDJude - I have a lot of reading to do!
Thanks again @chris101 - incredibly helpful information. Hmm, I have been avoiding the multiple LED concept based on previous prototypes where the multiple LEDs cast duplicate ‘stars’ through each star hole. However, I expect I can get around that by adding dividers within my dome to segregate the LEDs. Far simpler also to use multiple ‘Long LED’ modules over customizing for one custom light. Thank you! I hope to finish it up soon - I’ll post the end result when I do! Cheers!
@straylight Sorry I dropped out for a few days, if I say the last 10 days were somewhat ‘taxing’ I think you’ll understand what I’ve been busy with… Your planetarium project sounds great! I painted my favorite constellations (Pole Star and Big Dipper, Orion, the Seven Sisters, and Scorpio) on my ceiling in glow in the dark paint when I was a kid.
@straylight6 Sorry I was MIA for so long, I hope you understand when I say the last week or so has been ‘taxing’. Your planetarium sounds awesome. I painted constellations on my ceiling with glow in the dark paint when I was a kid.
Some of your ‘fuzzy’ issues may be related to the holes themselves, and their size/shape, they might need to be different sizes to get the effect you want. Some holes may be focusing the image of the LEDs internal parts instead of a point of light. Read up on ‘camera obscura’ or ‘pinhole cameras’ on how a tiny hole can act like a lens.
I say forget about ‘skill level’, it’ sounds static and hard to change. Use your expanding ‘skill set’ to meter your progress.