All posts by Windell Oskay

About Windell Oskay

Co-founder of Evil Mad Scientist Laboratories.

Linkdump: May 2020

Map in coronal frame with bird pertching

Linkdump: April 2020

Illustration of spacecraft and orbits for lunar landing

Linkdump: January 2020

PCBs swung out on wiring harness acting as hinge or book spine

The AxiDraw MiniKit

AxiDraw MiniKit

Today we are introducing a brand new member of the AxiDraw family of pen plotters: the AxiDraw MiniKit.

AxiDraw MiniKit
The AxiDraw MiniKit is a special compact addition to the AxiDraw lineup.

Designed for lighter-duty applications, It takes up less desk space and less storage space. With a plotting area of just 6 × 4 inches (150 × 100 mm), it’s small enough to take with you, or to fit into places where bigger machines can’t.

AxiDraw MiniKit
In addition to be being “Mini”, it is also a kit.

Unlike other models of the AxiDraw family like AxiDraw V3 and AxiDraw SE/A3 (which come assembled, tested, and ready to use), the AxiDraw MiniKit is a machine that you assemble yourself.

We’ve taken great care in designing a kit that is rewarding to build and to own.

AxiDraw MiniKit

And of course, it’s an AxiDraw, and performs like one. Small but sturdy, it’s built with custom aluminum extrusions, machined parts, attention to detail, and care.

Our Thanksgiving Weekend Sale


It’s our Thanksgiving Weekend Sale! use checkout coupon code TURKEY to save 10% storewide at Evil Mad Scientist.

Save on popular items like the brand new AxiDraw MiniKit, surface-mount 555SE and 741SE soldering kits, and everything else too.

Our biggest sale of the year, it’s a great time to get that AxiDraw SE/A3, EggBot, or through hole 555 kit too.

Sale runs through Monday, December 2.

The 555SE and 741SE surface-mount soldering kits

555SE and 741SE kits

Today we are pleased to announce the release of two new soldering kits: the 555SE discrete 555 timer and the 741SE discrete op-amp.

Both of these new kits are surface mount soldering kits — our first surface mount soldering kits — and we think that you’re going to love them.

555 kits, big and small

You might be familiar with our Three Fives discrete 555 timer and XL741 discrete op-amp kits. Both are easy soldering kits that let you build working transistor-scale replicas of the classic 555 timer chip and the famous µA741 op-amp. Those two are constructed with traditional through-hole soldering techniques and are styled to like “DIP” packaged (through-hole) integrated circuits.

Our new 555SE and 741SE kits implement the same circuits, now with surface mount components, and are styled to look like smaller “SOIC” packaged (surface mount) integrated circuits, complete with a heavy-gauge aluminum leadframe stand. Side by side with their through-hole siblings, the new kits are exactly to scale, with half the lead pitch and a lower profile.

555SE kit for scale

The 555SE and 741SE kits each come with eight (tiny) color-coded thumbscrew binding posts that you can use to hook up wires and other connections.

You can also probe anywhere that you like in these circuits — something that you generally can’t do with the integrated circuit versions.

741SE kit close up

The new 555SE and 741SE circuit boards are black in color, with a gold finish and clear solder mask so that you can see the wiring traces between individual components. There are a few other neat details here and there, such as countersunk holes for mounting the board to the leadframe.

The surface mount components are relatively large, with 1206-sized resistors and SOT-23 sized transistors, and assembly is straightforward with our clear and comprehensive instructions. These kits are designed to be a joy to build, whether you’re an old hand at surface mount soldering, want some practice before tackling a project, or are introducing someone to it for the first time.

Family portrait

And here is the new family: XL741, the Three Fives, along with the new 741SE and 555SE.

You can find the datasheets and assembly instructions for these kits, as well as links to additional documentation, on their respective product pages.

Both new kits are part of our ongoing collaboration with Eric Schlaepfer, who we have worked with on a number of dis-integrated circuit projects including the four kits here and the MOnSter 6502.

MOnSter in a box

MOnSter 6502 in enclosure

For the past couple of years we have been working towards a public launch of the MOnSter 6502, our working transistor-scale replica of the famous MOS 6502 microprocessor.

One of the biggest pieces of the puzzle has been how to present it in such a way that shows off its beauty but also lets you see it in action. Here – finally – is the result of that effort: An elegant shadowbox frame with hidden electronics and integrated buttons.

If you’d like to see the MOnSter and its new prototype enclosure, this weekend is the perfect opportunity: we are exhibiting it at the 2019 Vintage Computer Festival West, August 3-4 at the Computer History Museum in Mountain View, California.

MOnSter 6502 in enclosure

Where to go from here? If everything goes well, we’ll be launching the MOnSter this fall. Stay tuned!

Stroke fonts from Quantum Enterprises

One of the features in our new Hershey Text v 3.0 software is the ability to extend it with new fonts.

One company, Quantum Enterprises, is already selling high quality stroke fonts that are compatible with the new Hershey Text, and ideal for use with the AxiDraw.

Their fonts are available in matched pairs: A TrueType (outline) font and a single-stroke SVG stroke font. The TrueType font works as a regular computer font, which you can use to lay out and edit text on your page. Hershey Text then performs automatic font substitution replacing the text in place with the matching stroke font.

Here is a sample of what one of their regular (TrueType) handwriting-like fonts looks like, as laid out on the page within Inkscape:

And, here is how that same text looks once rendered with Hershey Text into its single-stroke SVG font version:

The single-stroke text comprises a set of paths ideally suited to be traced with a pen. And finally, here is how that stroke text looks as plotted with the AxiDraw:

These new stroke font pairs, as well as custom fonts, are available to purchase directly from Quantum Enterprises.

An especially neat feature of these fonts is that they can work with the Quantum Enterprises Scriptalizer character substitution software — now available directly integrated within a special version the AxiDraw software. This software performs automatic substitution between different letter forms (glyphs) for the same character, making plotted text look more like handwriting.

The AxiDraw CLI and Python API

Following the release of our new AxiDraw software this week, we are pleased to announce the release of two additional software components that greatly extend the capability of the machine.

The AxiDraw software is now available in two alternate versions that may be helpful for developers or for anyone who would like to control the machine programmatically rather than through Inkscape: A stand-alone command-line interface (CLI) tool, as well as a full-featured Python library.

The AxiDraw CLI

The first new tool is the AxiDraw CLI,  a command-line API to drive the AxiDraw outside of Inkscape. Like the Inkscape-based software, its primary function is to plot SVG files. However, it is a stand-alone utility that can be driven from within shell scripts and other environments that make use of shell commands.

Once installed, plotting a file can be as simple as executing the following command:

axicli filename.svg

There are, of course, a breadth of different modes and configuration parameters available. We have written detailed descriptions of each of these options in our comprehensive API documentation. The CLI also supports the use of configuration files to quickly switch between different sets of parameters.

Since most common scripting and programming environments allow one to call shell commands like this, that allows the AxiDraw to be used directly within a wide variety of frameworks.

 

The Python API

The second new tool is the AxiDraw Python API. The AxiDraw CLI is written within Python, and we have both exposed and expanded upon that nucleus to create a flexible and powerful Python module, complete with its own comprehensive documentation.

Just like the CLI, the Python API can plot SVG documents; it can both read SVG files and accept strings containing SVG data.

It also has features that are not available within Inkscape or the CLI: It supports direct interactive XY control. You can use absolute or relative moveto/lineto type commands to control the AxiDraw from within your own programs. This is particularly useful for a wide variety of potential AxiDraw applications that are not writing or drawing, but otherwise making use of the AxiDraw as a low-cost motion control platform.