Tag Archives: holiday

Evil Mad Scientist Valentines: 2015 edition

Lo Res Valentines valentines

For each of the last two years, we’ve released sets of “Download and Print” cards for Valentine’s day. The 2013 set had six equation-heavy cards, and the 2014 set was a set of six symbol-heavy cards.  This year, we’re releasing six new cards, bringing the collection up to a total of 18 cards. This year’s new cards feature love, hearts, and arrows (but no bows or cupids):

My love for you is real

For when your love is complex, but not whatsoever imaginary.

I love you more every day

For that moment when you want to express that not only is the first derivative of your love positive, but so is the second.

Our love is off the charts

(Just in case there was a danger of none of these being sufficiently cheesy.)

You make me glow

Not sure how we missed this one in last year’s set of symbols.  Alternate caption: “You light up my life.”

Solve for i

And what better way to say “I love you,” than with the gift of a math problem?

2015 Evil Mad Scientist Valentines
Lo Res Valentines

You can download the full set here, which includes all 18 designs from the three years (a 765 kB .PDF document).

As usual, print them out on (or otherwise affix to) card stock, and [some steps omitted] enjoy the resulting lifelong romance.

From the mailbag: DIY holiday lights

Chris wrote in:

I wanted to say thank you for writing your blog and the products you’ve created.  I used both to make my christmas lights this year.  Couldn’t have done it without you.


I used an ATmega xx8 mini dev kit programmed with an ISP shield to control a series of WS2811 LED pixels to make beautiful light. The controller is designed to be standalone, not part of a bigger system. I used a BCD thumbwheel switch to select up to 10 looks.


We can give credit to the FastLED Library team for the heavy lifting.  The case is from your friends at Adafruit. The target boards don’t quite fit in the Adafruit cases.  Thankfully ya’ll had the schematic PDFs posted and I saw I could literally cut corners to make them fit.

Back to why I appreciate what you do so much, growing up my dad tried to teach me about electronics.  He was putting motorola 6802 CPU’s in Sperry New Holland hay bale wagons.  Unlike how easy we have it today with Arduino he had to program in assembly…


I got a degree in Theatre and loved doing sound and lighting design.  So I really love the art you put into your technology. I’ve built many of your kits.  My favorite are the interactive LED panels.  Blinking lights!  I like to put them behind the ikea glass “white boards” so my ideas really shine when I write them down.  I’m looking forward to seeing what you do in 2015!

EggBot holiday project roundup

It’s close to the holidays, which means people are pulling out their EggBots and getting creative. Last year, we posted a set of holiday designs and some tips for working with ornaments. Here are a few projects we’ve found this year.

Erin Ruppert made this lovely “First Christmas” ornament. The gold ink looks great on the clear ball.

Erin also made ornaments with ornaments on them, which somehow seems fitting.

Lotte made an ornament for her mom at FABKlas, a maker education program.

The folks at FABsterdam made this Mario ornament.

MAKE Ventura used gold Sharpie markers on a matte finish ornament to great effect. Other makerspaces are playing with their EggBots, too. The Johnson County Library in Kansas is doing Eggbot ornament tutorials in their makerspace.

Chris Lynas took the EggBot to “work and school Christmas fair raising money for charity – result: £200 in under four hours!”

Fran marked up eggs for a family igloo making craft party.

Lastly, our friend Miguel engraved glass ornaments with his EggBot.

Solderless Flickery Flame

We’ve talked previously about making simple LED pumpkins with candle flicker LEDs. Lately we’ve been playing with making better looking flames by using multiple independent flickering LEDs with different colors and lens styles. It makes a spectacular difference: it goes from something that looks like, well, a flickering LED to something that really looks like there might be a flame in there.

The end result is pretty neat: A compact battery powered “flameless flame” that looks great in a pumpkin, luminaria, or as a stage prop. The interplay of the different LED types and colors gives an ever-changing and shifting flame display.

Other than the candle flickering LEDs, the parts are commonly available. We’ve also bundled them together in the Solderless Flickery Flame Kit.


  • Battery Holder (2×AA with switch)
  • Mini-breadboard
  • 6 × candle flicker LEDs (2 red diffused, 2 yellow diffused, and 2 yellow clear lens)
  • 6 × 68 ohm resistor
  • 2 × wire jumper
  • White paper bag (optional)

Also needed:

  • 2 × AA Batteries (not optional)
  • Wire clippers, cutting pliers, or “beater” scissors (optional)

Hook up the battery holder to the breadboard several rows apart to give enough room to install the resistors and LEDs. Optional: peel off the backing on breadboard and adhere it to the battery holder. Connect each LED with its own 68 ohm resistor. (Use the “in parallel” method from this article.) The extra jumpers are included to help bridge across the center gap in the breadboard.

Trimming the resistor leads will keep the breadboard tidy, and help prevent short circuits. Trimming the LED leads to varying heights will help distribute the light in different ways.

The white paper bag included with the kit can be used for creating a traditional luminaria or for making a ghostly halloween decoration.

You can find more Halloween decor projects in our Halloween Project Archive.

Evil Mad Scientist Laboratories Valentine Projects

Evil Mad Scientist Valentines, 2014 Edition

Lo Res Valentines

Last year we released a set of six equation-heavy “Download and Print” cards for Valentine’s day.  This year, we’re doubling the size of the collection (to twelve!) by adding six more cards, this time heavy in symbols, not equations:


You turn me on” …with an SPST switch.


I can hardly resist you.

There is room for a future superconductivity joke here, involving a phrase like “I can’t resist you (below a certain temperature).


You can download the full set — including the 2013 cards — here, a 500 kB pdf document.

As with last year’s set, print them out on (or otherwise affix to) card stock, and [some steps omitted] enjoy the resulting lifelong romance.

Update: The 2015 set has been released!