Mini-Review: Elecrow Laser Engraver Tool

Elecrow Laser Engraver Tool - 3/4 View

Disclaimer: Contains Amazon Affiliate and direct links

For $130, what could go wrong? Naturally we ordered two of this tiny, 1W laser engraver tool, because that’s just how we do things. One device arrived DOA (seemed to be the controller board), one worked (as well as expected, that is to say, there’s no comparison to a real machine).

What’s in the Box

The laser machine, some sample materials, a 5V 2A power supply, and a USB stick, because who wouldn’t trust a USB stick, amiright?

Fit and Finish

On the working device, while the laser head was attached, it wasn’t attached well. Two screws were complete missing (the top two), the bottom two were quite loose. Tightening them required moving around the head using the included software and a small screwdriver–this is not a machine built for trivial fixery.

The top is removable via plastic tabs, but it’s a pain. The top is more or less required for reliable operation since it keeps the Y axis rails in place–if you take off the top, before doing much printing, you’ll either need to put it back on, or replace it with something that’ll hold the rails.

It comes with a 5V 2A power supply with a too-long barrel jack that occasionally falls out. The USB port is far enough in that some cables won’t fit, meaning it also fell out. We didn’t mean to lose connection 🙁

Once both USB and power are plugged in the laser turns on (low) for help in positioning. We needed to re-focus ours; just turn the lens cap until it’s as close to a pinpoint as possible. Use white, non-shiny paper for this step.

There’s an acrylic piece you can put on the front, which is great for keeping your eyes safe(r), but there are no side panels. Even though it’s just a 1W laser, you can be hurt by even scattered light, so be careful… None of us are blind yet, but we did occasionally get zapped with scatter enough to notice it.

There’s an “exhaust fan” on the back which does actually pull out smoke from the cutting area (more or less) but it’s not going to save your life or anything: cut responsibly.

The Software

Well, it’s software, sure enough, but holy smokes, you sure can’t do much with it. And what you can do is largely guesswork, at least on the Windows version. We haven’t tried the OS X version yet, and our Linux machines are left in the lurch.

The Software
The Software

There’s a collection of sample images we used for our initial testing. You can scale the images using the “Scaling” slider (upper-left) and if you don’t, you’ll get tiny, burned chunks. Larger, clean images will work best. You can add text using whatever fonts you have installed, but with zero means to align anything anywhere, your composition options are limited.

Laser Etched Samples
Samples

Homing the machine? It just moves until it grinds in the corner then pops out a little bit. Laser intensity? “Depth adjustment of engraving”. About 5-10-ish is decent enough, and it takes about three minutes for their sample Lexus logo image to etch on cardboard, but again, finding the sweet spot for the material being etched is sketchy, especially since you can’t enter a number directly–sliders all the way, baby!

It often failed to print the entire image for no reason we could discern, like the Big Bang Theory image. Sometimes it would skip parts of an image, as in the Bentley logo’s “L” and part of the “N”. Again, finding the intensity sweet spot was very hit-or-miss.

Cutting paper seemed… essentially impossible with the software. Fine for us (although it’s a potentially handy feature) but doesn’t make any sense for even the simplest of laser devices. We couldn’t find any way to do much of anything except raster images, which could be used to cut, but it’s slow, and even a 1W laser should have no problems cutting out hairline vectors.

Our Advice

Either try the higher-powered one (a clone with 3W laser) or get a real laser. This might be a useful toy, but as shipped, it’s not worth the effort we’re putting into it.

Next Up

Total hackage, of course: since we had a working device for testing, and a non-functional device, we wanted to bring it into the fold of devices we could use across our operating systems and usecases.

Unfortunately, the computer doesn’t talk GCode to it, meaning that either (a) the protocol had to be reverse-engineered, or (b) replace their controller board with something more-standardized that would work with other software out-of-the box. True to form, we chose (c), all of the above.

In Part II we’ll look at their native comms protocol and see if it’s worth dealing with at all (hint: nah). Then in Parts III and IV we’ll take our dead unit, graft a controller onto it, and turn it into the device we wanted in the first place: take it to a workpiece, burn it with lasers, and run away.

Resources

Products

Mini-Review(s): Box Cutters

Disclaimer: Contains affiliate (and direct) links to some reviewed products.

Have boxes? Want to open them? Get you a box cutter for a great good! TSA aside, box cutters are great: yes, we all have our multitools and combat knives strapped liberally around our body, but for all-round utility, it’s hard to beat the simple box cutter. (And they make serviceable weapons in an emergency, and raise fewer eyebrows than a wave-opening Emerson Karambit, our go-to death-dealer of choice.)

From simple to elaborate, from light to heavy–we’ll give a quick overview of the ones we have laying around the shop, and discuss why some are better than others, what our daily carry is, and why.

(We won’t discuss scrapers, which are something different, but maybe some other time–they’re also super-useful, but not as fun for… cutting boxes.)

MOAR BOXCUTTERS!!1!

A pile of box cutters
Pile o’ Box Cutters

These are a few of our around-the-shop cutters (tragically this is not all of them; we have more tools than sense). There are three main “classifications” of box cutters: flippers, sliders, and “always-on” (those come with sheathes). We’ll work in reverse-order.

Always-On

Pull them out of the sheath, cut a box: it’s as simple as that. The problem with them is that they essentially require a sheath or container. They may be suitable for bench mounting (and we have one stuck on to one of our CNC tables) but for daily carry it’s a non-starter. Why?

Sheathes add bulk, and unless it’s sized exactly right, and it’s a pretty tight clip, you either need to hold on to the sheath to deploy, or push down on the sheath while you draw the cutter. So why would you want one at all?

Rigidity: these are easily the solidest variety of box cutters. With a heavy frame and no moving parts you’ll break the blade before you have any other mechanical problems. They’re worth having on hand for that reason alone, but if you’re anything like us, you’ll use them only rarely, or only when you’re near where one is mounted. They’re also fine in a toolbox or tote, but in general, we think they’re more specialized.

We only have a few varieties of these, but we like the Stanley for overall durability, even if the sheath feels a bit cheap, and the belt clip… well, there’s a clip, it’ll go on a belt, but deploying is a bit of a pain.

Sliders

These push the blade out the front. They’ll either use a standard box cutter blade (the trapezoidal ones) or a custom blade, often with snap-off blades to get to the sharp part.

Mechanically they’re generally quite sound, and less prone to failure and breakage than a flipper (up next) because they just run on a track–there’s no pivot to get gunked up and even a pretty dirty one can be easily forced open.

The snap-off blades are a bit more specialized; they’re wonderful for foam cutting (hard to beat, in fact) especially if you sharpen them. For this variety we like the DeWalt (they’re yellow!) and a Kershaw sharpener. The downside is that they take only specific blade types and shapes. They’re also (generally) thinner than their “conventionally-bladed” counterparts so for heavy-duty use you’re better off elsewhere. That said, the blades are much longer (good for foam, bad for cardboard)/

Either type is fine in a pocket (as long as you remember to retract the blade… be safe, kids!) but don’t always include a belt clip. Without the belt clip, at least for us, their use as a daily carry is limited, but they’re great in a toolbox. The DeWalt snap-off cutter has a pocket clip that’s quite robust, and while we don’t carry one daily, when we need to, we can, with confidence.

For “conventionally-bladed” sliders we like the Stanley Fat Max.

For snap-off we like the DeWalt DWHT10038, and use a Kershaw stowable sharpener between cuts. (“Between all cuts?!” you ask? Depends; for foam, pretty much–but we have dedicated units for foam. For general cutting, not really. But for foam it’s arguably worth the extra effort.)

Flippers

For daily carry we like flippers, in particular this Milwaukee flipper, because it’s a one-handed opener, basically a gravity-operated switch blade: it swings really easy. This is also its greatest weakness–there’s a bit of rattle-and-shake when it’s in the locked position. But the convenience and extra functionality (a strap cutter and wire stripper) make up for it for most uses.

We’ll give an honorable mention to our pals at Home Depot for their Kobalt stainless steel flipper. Make no mistake–it does not flip; you have to want to open this bad boy. But when it’s locked it’s nearly as solid as any always-on box cutter, and we have several, mostly in toolboxes and glove boxes.

Products

The Stanley fixed-blade as we have it doesn’t appear to be sold any more, and since we don’t own any newer versions, we don’t know if we can recommend it or not, so no link to that for you.

The Kobalt Stainless Steel may be available at your local Home Depot, but searching for it proved… somewhat irritating, so we gave up. It’s not a daily carry anyway (too heavy, too hard to open) but man, is it solid.

Affiliate Links

Direct Links

Quick Look: Makerfocus NodeMCU Board with 18650 Battery On-Board

Disclaimer: This post has affiliate (and direct) links to the reviewed product on Amazon.

As fun as adding a voltage booster (for 5V projects) and/or voltage regulation and a charge circuit is to our designs, sometimes it’s nice to just have everything done for us. We’re big fans of the ESPxxxx/NodeMCU ecosystem: they’re cheap, they’re WiFi-enabled out-of-the-box, they’re small, and they’re usable in the Arduino ecosystem if that’s how you roll.

We found this little guy on Amazon:

It’s a NodeMCU-compatible board with a built-on 18650 battery holder and charge control circuit: it may end up being one of our go-to designs when we need a battery-operated, low-IO WiFi-enabled part (a disturbingly-frequent ask), barely larger than the battery itself. Slick. Let’s take a look, and do a sanity programming check.

Major plus: MOUNTING HOLES. Boards without mounting holes are a real pain. Minor drag: the 18650 battery holder is on the back, so you’re not going to pop this bad boy in a breadboard any time soon, unless you put some longer headers on the top of the board, and don’t mind not being able to hit the switches or see the lights.

The Guts

The brains is an ESP-WROOM-02 (see links in Resources) with a Silicon Labs CP2102 handling USB comms. An Advanced Monolithic Systems AMS1117 chip regulates the volts, charging is controlled with a Nanjing Extension Microelectronics TP5400 (whose datasheet I could only find in Chinese 🙁

The LED near the charge controller will be red when charging, green when charged or under USB-only power. You can charge and run the board at the same time. We see solar in this board’s future.

The Setup

There are a number of steps to make this work in the Arduino environment; you may want to go a different route–but we needed to keep in the Arduino ecosystem to keep our classes as uniform as possible.

  • Install USB Driver
  • Add Board Manager URL
  • Pick a board, any board
  • Set the RESET method

Install USB Driver

You may need to install a driver for the Silicon Labs CP2102. Drivers are available on the Silicon Labs CP2102 Driver Downloads page for major environments.

For OS X (the only one we’ve tested so far) you’ll get a ZIP file with a disk image (DMG). Unzip, open the image, and run the package file Silicon Labs VCP Driver.pkg, and do the normal package install thing.

Add Board Manager URL

If you haven’t already been using ESP-ish boards you’ll need to add a board manager URL to the board manager. In the Arduino IDE open the preferences via Cmd-, or the menu. The list of board manager URLs is a comma-separated list.

Board manager dialog box with board manager URL text box highlighted
Board Manager Dialog

To it add:

http://arduino.esp8266.com/stable/package_esp8266com_index.json

Pick a Board, Any Board

For this mini-review we stuck with a generic 8266 board. Under Tools ⇨ Board choose “Generic ESP8266 Module.”

Board selection drop-down menu
Board Selection

Set the RESET Method

To upload our sketches to the board we need to set the RESET method under Tools ⇨ Reset.

Shows board drop-down method with board reset method
Reset Method

We didn’t need to make any other changes to get the basics working.

The Glory

The “documentation” on the Amazon product page states that the on-board LED is on GPIO16, so our go-to example, Blink, will use pin 16 for the LED:

#define LED 16

void setup() {
  pinMode(LED, OUTPUT);
}

void loop() {
  digitalWrite(LED, 0);
  delay(250);

  digitalWrite(LED, 1);
  delay(250);
}

If you’ve followed all the steps above (and do let us know if we’ve left anything out) you should see an attractively-blue blinking LED.

We’ll be revisiting this board both here and in our upcoming Maker’s End Inspiration Series book, ESP Inspiration, so stay tuned–this little guy is going to get some projects!

Resources

Products

Review and Build: Pimoroni Keybow, a blinky auxiliary keyboard

We love our keyboards, from mechanical to split to Apple Magic. We also love our shortcuts, and even with a zillion macro programs, we still sometimes “need” dedicated keys for our most-used apps and application shortcuts (here’s looking at you, every CAD program ever).

We’re purchased a multitude of commercial keyboard “extensions” over the years, from industrial-strength over-priced 16-key strips to products designed for video editing. We’ve put together several cobbled systems using touch screens and Arduinos and Raspberry Pis. They’ve all worked, to some extent (we’ll detail some touchscreen builds in an upcoming post since they’re quite similar to this product, and provide extra blinkage).

We were attracted to this product because it’s a mechanical solution, and its underlying platform has extra capabilities and versatility: this is a 12-key matrix with an RGB matrix under each key, powered by a Raspberry Pi Zero WH. This opens up a world of keyboard possibilities and hacks.

It’s (marginally) pricey at £49.98 (about $65USD plus post) so it won’t be saving you much money over commercial solutions, but the open platform and trivial hackability are attractive. That said, if you already have a keyboard that suits your needs, you might be better off hacking in the RPi yourself. But we love Pimoroni and throw money at them often, so yep.

What’s in the Box

PARTSES. There’s the Pi0, a PCB for the keys, the keys, the keycaps, two acrylic plates, rubber feet, and connection hardware.

You’ll need a micro-SD card, so be prepared. We were not, and had to wait.

But it can be a small one, they claim a 1G card is sufficient. We used 8G because we had them.

The problem with micro-SD cards? They’re micro, and we’re old.

The board includes an I2C breakout for adding peripherals (we’ll use this in an upcoming build) and runs a mini-Raspbian OS called Keybow OS to get things done. Interface customization is handled by Lua, an embeddable scripting language with great functionality.

The Build

This is not a tricky build: there’s no soldering, just press-fitting and screwing a few tiny screws and bolts that our fat fingers occasionally dropped: it wouldn’t hurt to have a few extra M2.5 parts on-hand just in case (we buy them by the mixed-case every now and then; we’ll throw up a post about keeping the shop stocked some day).

The assembly docs on the Pimoroni site do a great job of piecing it together; we’ll add a few details, but generally just follow their docs.

Prepare Baseplate

  • Remove protective sheets from acrylic parts (we hate this part; be careful on the thinner spacer piece).
  • Stick on little rubber feet. (Unless you’re going to mount it some other way, like in a 3D-printed stand–see below!)
  • The “Keybow” text should be on the lower-left, facing you, not backwards. This is the bottom of the device.

Attach Raspberry Pi Zero WH to Baseplate

  • Use two M2.5 screws and nuts on the front of Pi0 (the long edge with the USB ports) to attach to the thicker baseplate.
  • Attach it to the side without the rubber feet, e.g., the “inside”.
  • Don’t over-tighten the screws; acrylic loves to crack.

Attach Keybow PCB

  • Remove standoffs’ protective film on pCB ferrules
  • Mount standoffs on the PCB
  • Line up the Pi0’s GPIO pins with the header on the PCB.
  • Press to fit; support whichever side you’re pushing against.

Mount Switches

  • Push each switch through the “gold leaf” PCB, from the gold leaf side down. Make sure each key is seated evenly.
  • The “gap” on the underside of the keys (where the pins are, and where the plus-shaped plunger/switch is not) should be oriented to the top of the gold leaf PCB.

Mount Keycaps

  • Press each keycap onto the switch. They’re all the same, and symmetrical, so orientation doesn’t matter.
  • Support the bottom of the switch when you press: it’s a tight fit.

Mount the keys to the PCB

After the pins are all aligned just push it into the PCB, firmly and evenly.

The Software

The Keybow runs a tiny version of Linux based on Raspbian. To install it onto the SD card download the latest ZIP or TAR file from the Keybow OS GitHub Releases page. Un-archive it and copy the files from the sdcard directory to the root level of your SD card.

To restate: everything under the sdcard directory (highlighted in the image at right) should be at the top level of the SD card’s root directory.

The Default Layout

It’s a numeric keypad like on a PC keyboard, e.g., 7-8-9 are on the top row, and 0-.-[ENTER] are on the bottom row, when the USB cable is sticking out the right-hand side of the Keybow.

It also comes with some sample macros; we’ll discuss updating them, various ways to poke the RGB LEDs, and some more fun stuff. We’ll be using it horizontally, and will detail macros, customizations, and using the Pi0 in our next (and final?) Keybow post.

Smoke Test

  • Put the MicroSD card into the Raspberry Pi
  • Plug in a USB cable
  • You should see some blinky lights

Any Problems?

If we have any complaints it’d be around the USB cable location and cutout. We would have preferred the RPi be firing towards the back so the USB cable would have a straight shot out the rear. Barring that, a larger cutout for the USB plug itself to support right-angle connectors so the cable could run out the side might have been a better choice.

Additionally, we had to hunt around to find a Micro USB cable that would seat properly in the keyboard due to the small size of the cutout. The problem was at least partially solved when we broke the thinnest piece of the spacer acrylic by accident: you may want to break it on purpose.

Going Further

3d printed keybow stand
3D Printed Keybow Stand

Naturally we built a small box for it; the design is available on Thingiverse. The initial version for sizing is a bit tight, and keeps the entire build visible. We might do a version with taller walls with a slot for the USB cable. The rubber feet were stuck on the bottom of it so it wouldn’t slide. (It’s not hollow; hollow might be better to allow adding some weight.)

Instead of mounting it on its rubber feet you might prefer to drill out some holes, countersink the board-side’s holes, and screw it onto a platform (like at an angle). Or omit the rubber feet and 3d print a small angled platform with some spaces for the screw heads. Like we did.

Resources

Quick Look: DFRobot Beetle BLE

Beetle BLE Front

Disclosure: This post contains affiliate and direct product links.

We have several projects that have low pin counts and require some form of connectivity. We found the DFRobot Beetle BLE to be a great fit for those projects (some of the builds will be documented; we’ll update this post as the build posts are updated).

A (tiny!) Arduino Uno-alike with on-board BLE, perfect for low pin count projects that require BLE connectivity.

Basic Features

It’s basically an Uno with a reduced pin count, so you get the expected functionality, just less of it:

  • ATmega328@16MHz
  • Digital: 4
  • Analog: 4
  • PWM: 2
  • UART: 1
  • I2C: 1
  • Micro USB: 1
  • ~ 29mm x 33mm

There are also dual ICSP interfaces (unpopulated), one for the 328P, and one for the CC2540 BLE chip.

The docs state it’ll take up to 8V (although we’ve only ever used USB or a reasonable 5V supply).

The I2C (SCL/SCA) and UART (TX/RX) pins are also broken out on the bottom of the board as pads: you’ll need to tweak your normal dev process if you plan on utilizing that functionality.

The Play Bluno app (iOS, Android) app allows interaction with the board, but any reasonable Arduino/BLE app should work.

Using The Beetle BLE

It shows up as an Uno–doesn’t get much easier than that! Under OS X the port shows up as a USB modem as you’d expect, with the additional “Arduino/Genuino Uno” tag. Since it’s an Uno, all default Uno sketches (that respect the Beetle BLE’s limited IO) should work right out of the box.

What is it not for?

  • IO-heavy projects
  • WiFi
  • Forget standard headers and breadboarding 🙁
  • Trivially mounting: it’s an odd shape (wearables, anyone?)
  • TODO 3D Printed Simple Mount

What’s Next?

We’re writing up a complete review with some tips for getting started and simple starter apps. We’re also using the board to power a tracked smart car chassis–both the chassis and build project will have their own posts.

Competition

There are a lot of similar boards these days, our favorites are products from the Adafruit Feather line:

Those are larger boards with a full complement of IO, and a wide variety of add-ons (“Feather Wings” in Adafruit-speak). For demanding projects they’re probably a better choice. (Quick and full reviews coming, naturally.) They’re also more expensive (by about $10-15), so if you don’t need the additional power for a specific project, the Beetle BLE is a great little board.

Reference Links

Product Links