About Windell

Co-founder of Evil Mad Scientist Laboratories.

Mega Menorah 9000!

MM9k

MM9k  MM9k

Introducing our newest Hanukkah menorah kit: Mega Menorah 9000!

This is a great new easy soldering kit to make a handsome and decently-sized menorah. Once built, it stands just over 6 inches (15 cm) tall, and is 7.5 inches (19 cm) wide.

It’s USB powered, USB programmable with a built-in interface based on the Adafruit Trinket, and features 9 discrete RGB LED “pixels” that can produce all kinds of bright colors. Flickery flame effects built in too, of course.

MM9k

One of the cool things about this kit is that it has a unique “Trompe-l’œil” circuit board design that gives some illusion of a rounded 3D surface. As you can see above, it’s actually flat as a board.

To make it, we started with a 3D CAD model of what we wanted the circuit board to look like. The outer contours of the model became the outline of the circuit board. We then rendered the CAD model, and used our StippleGen 2 software to convert the resulting image into a vector stipple drawing— one that could eventually be converted into the artwork for the circuit board. All together it’s over 9000 stippled dots of black silkscreen! (To be more specific, there are roughly 17,000 dots on each side.)

MM9k FAQ: OK, but isn’t the name “Mega Menorah 9000″ perhaps just slightly on the excessive side?
Yes, we must (grudgingly) admit that it is. It just slipped out when we were trying to come up with a working title for the project — a name that meant “better than deluxe” so as to distinguish this model from our old favorite Deluxe LED Menorah Kits.
Alas, it was funny. And so it stuck. And now, it’s too late.

MM9k  MM9k

There are two circuit boards in the kit. The “top” PCB is shaped like a menorah and the components (mainly just the nine WS2812-style LEDs) are for the most part hidden on the back side.

The base circuit board has rubber feet, the control buttons (color, night, reset), an ATtiny85 AVR microcontroller, USB power/programming jack, and a programming indicator LED. The circuit is actually an implementation of the Adafruit Trinket, which allows for reprogramming the microcontroller without requiring any hardware other than a regular USB cable.

MM9k FAQ: Why is there a binder clip there?
It’s an assembly jig that helps to align the parts in place so that it’s easy to build and looks neat. We’ll write more about it later.

MM9k

And, wow does this thing do colors! The nine WS2812-style individually addressable RGB LEDs in 5 mm packages, look reminiscent of candle flames, but can be tuned to just about any color in the rainbow. From a control standpoint, it’s awfully nice that they’re managed by just a single pin of the microcontroller, and have the built-in ICs to handle colors and dimming.

Mega Menorah 9000 begins shipping this week.

The DIYIC Protoboard

Introducing our new kit, DIYIC, which stands for “Do-It-Yourself Integrated Circuit!” This breadboard-style solderable proto board is shaped like a giant integrated circuit. It’s a freeform complement to our 555 and 741 “dis-integrated circuit” kits. Make your own custom 8-pin integrated circuit, use it as a giant connectorized breakout board for smaller components, or however you see fit.

Fine labeling

The matte-black circuit board is extra thick and has subtle white markings including an alphanumeric grid and pin number labels.

reverse side of PCB

The wiring pattern — that of classic breadboards — is easy to see by looking at the exposed traces on bottom of the board. Connections to the 8 terminal posts are through the three-position strips on the PCB; each is labeled with the corresponding pin number.

The DIYIC is available either as a bare circuit board or in a full kit, complete with the “Integrated Circuit Leg” stand and 8 color coded thumbscrew terminal posts.

Linkdump: November 2014

Ostrich EggBot 2.0

Ostrich EggBot
Ostrich EggBot

We’ve just released version 2.0 of our Ostrich EggBot kit!  This is the giant size EggBot. Like the smaller models, it’s a machine capable of drawing on the surface of all kinds of spherical and egg-shaped objects up to 6.25 inches (15 cm) in diameter, including large ostrich eggs.

This chassis of the new version is CNC machined from melamine-faced MDF, and laser engraved with markings and calibration scales. (The previous version was made of plywood; you can read about it here.) We’ve also updated the graphics, and rolled in a number of subtle improvements based on user suggestions and our own extensive experience with the machine and other members of the EggBot family.

Ostrich EggBot Ostrich EggBot

With a relatively large chicken egg chucked into the holders, you can get a better sense of scale. (An ostrich egg is a terrible object to suggest a sense of size!)

The tailstock (the sliding portion of the right hand side) has been slightly redesigned for higher stiffness and better ease of use. The bulk of the stiffness in the directions that we care about (that is, in the directions where the chassis material is not strong) derives from the steel angle brackets, and the new tailstock helps to reinforce that for better overall rigidity.

Ostrich EggBot

One of the best things about the new chassis material is that it laser engraves particularly well, giving high-contrast, highly readable adjustment scales on the sides. And that makes it all easier to use in practice. All considered, this has turned out to be quite a nice little upgrade.

A Requiem for CandyFab

Coil

The CandyFab 4000, 5000, and 6000 were three early DIY 3D printers that we built in the years 2006 through 2009. They worked by using hot air to selectively melt and fuse granulated media, and were capable of producing large, complex objects out of pure sugar, amongst other things.

CandyFab is no longer an active project — it hasn’t been for a few years. But the time has come to retire it officially and document its history. We have taken some time to write an in-depth article about the history of the CandyFab project, the different CandyFab machines, why and how they were built, what they were capable of, and the lessons that we learned in the process. Have a seat; we have a story to tell.

The CandyFab Project: 3D Printing in Sugar. Big, DIY, and on the cheap. 2006 — 2009.
Link: candyfab.org

Soldering Tip Tinning with Sal Ammoniac


If you solder, you’ve likely come across an “untinned” tip at some point— that’s when the tip of your soldering iron loses its shine, and doesn’t easily wet to solder any more.

Once your tip gets this way, it doesn’t make nearly as good of a thermal contact to whatever you are trying to solder, and it simply doesn’t work well. Soldering can take 2-10 times as long, and that isn’t good for your circuit board, components, or mental health.

You can sometimes re-tin the tip by melting fresh solder onto it, but that can be challenging, because the whole problem is that the tip isn’t melting solder. It’s particularly hard to keep tips tinned with modern lead-free solder, because it needs to get even hotter to begin melting.  If you get to this point, you might think about even replacing the tip.

But before you throw that tip away, instead consider using one of the “old standard” solutions, which is to refurbish the tip with a tip-tinning compound. And we came across the most classic of them in one of the most unexpected locations.  Continue reading

Introducing the EggBot Pro

EggBot Pro

An EggBot is a compact, easy to use art robot that can draw on small spherical and egg-shaped objects. The EggBot was originally invented by motion control artist Bruce Shapiro in 1990. Since then, EggBots have been used as educational and artistic pieces in museums and workshops. We have been working with Bruce since 2010 to design and manufacture EggBot kits, and our well-known Deluxe EggBot kit is a popular favorite at makerspaces and hackerspaces around the world.

Today we’re very proud to release the newest member of the family: the EggBot Pro, a near-complete reimagining of the EggBot, designed for rigidity, ease of use, and faster setup.

EggBot Pro

The EggBot Pro is as sturdy as can be: Its major components are all solid aluminum, CNC machined in the USA, and powder coated or anodized. (And isn’t it a beauty?)

The most common mechanical adjustments are faster with twin bicycle-style quick releases, and repositioned thumbscrews for easier access.

EggBot Pro

The frame also has an open front design that gives much better visibility while running, and greatly improved manual access when setting up.

EggBot Pro

And, it comes built, tested, and ready to use — no assembly required.  Assuming that you’ve installed the software first, you can be up and printing within minutes of opening the box.

The EggBot Pro begins shipping this week. We’ve also put together a little comparison chart, so you can see how it fits in with the rest of the family.

 

New Winches for WaterColorBot

We’ve just given the WaterColorBot a little bump up to kit version 1.5. The new version now comes with a pair of beautifully machined aluminum winches.

The winches are precision cut on CNC machines and anodized clear. We add a few extra little parts (flat-head rivets to wind the winch around, screws, and a stamped and polished stainless steel “clamp” to hold the string end), and wind them with the same “100 pound” Spectra cord as we did before.

We described the process of making and winding our older laser-cut wooden winches in our blog post about the making of the WaterColorBot, and again in our post about the  winch cutting jig. For better or worse, transitioning to the new aluminum means that we’re no longer using our older wooden winches that we described in those blog posts.  But in the end, these new winches are a better, more elegant solution.

 WaterColorBot kit version 1.5 is now shipping from the Evil Mad Scientist Shop.

The XL741 Discrete Operational Amplifier

Ever since we released our Three Fives discrete 555 timer kit last year, people have been asking us “When are you going to come out with a 741 op-amp?” It has taken us quite a while to get here, but the answer is… Today!

Our XL741 Discrete Operational Amplifier is a real, working op-amp that you can build yourself.  It’s a transistor-scale version of the original μA741 integrated circuit, that incredibly versatile and popular analog workhorse. As with our 555 kit, you can probe inside to see the inner workings of the circuit as it works. And, like our 555, it comes with a beautiful anodized aluminum “IC legs” stand, so it even looks great when it isn’t plugged in.

The kit was designed and developed as a collaboration with Eric Schlaepfer, and is a direct adaptation of the equivalent schematic from the original Fairchild μA741 datasheet.

If you’ve ever used operational amplifiers, you’re probably familiar with the μA741 (or colloquially, just “the 741″). Designed by Dave Fullagar and released by Fairchild in 1968, it’s the quintessential and most popular op-amp of all time. While newer op-amp designs easily outperform the μA741 in just about every possible respect (speed, noise, voltage range, and so on), the 741 remains widely beloved and in active production by multiple manufacturers even today — over 45 years later.

And, if you haven’t used an op-amp, this a great way to learn. Op-amps are simple, wonderful building blocks for making analog computers. With op-amps, you can build circuits that can (for example) add, subtract, amplify, take logarithms, perform integration, or perform other operations on your signals. Or buffer and copy them, or cleanly convert current to or from voltage, and on and on and on.

A regular op-amp is an integrated circuit; a little black box. The XL741, on the other hand, is a big black box, with a heck of a lot of points where you can can probe inside, to see what’s going on, in real time. And that’s a unique opportunity.

The XL741 is a quick, easy to build soldering kit, with through-hole components, and not too many of them. (And, have you see our awesome resistor wallets?)

And, best of all, the XL741 is in stock, and begins shipping today. 

Visit our store page for links to the XL741 datasheet, assembly instructions, and additional documentation resources.