Teknic Clearpath Servo motors installed on a G0704 CNC mill

I recently upgraded my mill to use Clearpath Servo motors. The motors I used are the CPM-SDSK-2341S-RLN which are 828 oz-in of torque.

The motors run really well. They are powerful enough for the mill, and are absolutely silent when they run – this was really surprising. I’d never realized how much noise the steppers made.

I swapped out 400 oz-in steppers for these servos. Interestingly, when I first installed the servos, they had trouble moving the table. This was before calibration, and also before I adjusted the power supply to output the full voltage (there’s a selector switch in the power supply for various input voltage levels). Once I adjusted the ways, lubricated the ways, and tuned the motors, the mill ran really well. I’ve been able to do heavy cuts and have never noticed an issue. I’ve been able to speed up the “rapid” speed of the mill to 100 inches/minute, from the previous setting of 40.

Teknic states that the servos can be one-half the rated torque of a stepper motor, but I’m skeptical, based on my experience.

The servos each have a USB port, and come with a windows application for tuning the motors. When the application runs, you can see the torque, maximum torque, speed, direction, etc. In the tuning mode, you first define a range of motion for the motors – say a 20 to 50 turn range where the motor can run safely. Then it enters a tuning mode where it applies different levels of torque, moves the mill slowly and quickly in each direction, and does loud jarring movements where the motor slams the shaft. It does this to analyse the resonance of the machine. It is scary to watch. It’s like your mill is being hammered with a sledge hammer! In fact, it loosened the set screws on the Lovejoy connectors (which were too small anyway).  The tuning takes about 20 minutes per axis.

Custom Keyboard for G0704 CNC Mill, controlled by PlanetCNC software

I recently updated my G0704 CNC mill to add an external keyboard for commonly used functions. My reason for doing this was that some of the functions I use most are really buried in the menu structure of the Planet-CNC.com control software I use on the mill.

For example, I use the Zero X Offset and Zero Y Offset all the time, yet these are in a menu 3 levels deep in the software. Also, I find that having dedicated buttons is a bit safer for functions like Start, Stop, and Measure Z Offset. In particular, the Measure Z Offset button on screen is right beside the Measure Tool Offset – which does really long tool measurement sequence, involving a fixed tool location measurement – really easy to select this by mistake.

My solution was to create an external box, with the 7 buttons I use most, and connect this box to the Control PC using USB.

CNC Custom Keyboard

Here’s a video about this project:

More Details:

The Planet-CNC.com control software has keyboard codes for each menu item. You can simply type the keyboard code when the program is running, and that menu item will be executed. For example, the keyboard code for Zero X Offset is “/45211” These keyboard codes are visible when you drop down a menu in the software.

I used a Teensy 2.0 Arduino controller, which is perfect for this application as it can be configured to emulate a USB keyboard. I connected the 7 buttons to pins 0-6 on the Teensy, and connected the other side of all the buttons to the Ground pin.

  • Pin 0 – Zero X Offset (Sends keycode /45211)
  • Pin 1 – Home (Sends keycode /470)
  • Pin 2 – Zero Y Offset (Sends keycode /45212)
  • Pin 3 – Zero Z Offset (Sends keycode /45213)
  • Pin 4 – Measure Z Offset (Sends keycode /459)
  • Pin 5 – RUN (Sends keycode /401)
  • Pin 6 – STOP (Sends keycode /406)

Here’s the Arduino Sketch (the program) that I used for this project.

The software scans the pins, looking for a pin to be “Zero”, which means a key is pressed. When it finds a pressed key, it uses the println function to send the Planet-CNC keycode to the software.

Note: The keypad sends the keycode to whatever program is running in the foreground on the PC. You shouldn’t rely on this for critical keypresses like ESTOP. The ESTOP key should be hard-wired to the appropriate pin on the Planet CNC control board.

Not A Glue (.com) UV Cured Plastic

This is an interesting product – a plastic that cures via UV light, similar to what dentists now use for fillings.

From their site:

“Bondic™ is The World’s First Liquid Plastic Welder and is the only product that Works where Glue FAILS! It’s liquid plastic that only hardens when you need it to. YES it stays liquid and won’t dry out like those crazy glues on the market today. With Bondic™ you can bond, build, fix and fill almost anything, it’s a 3D tool that fits in your pocket. Use it on plastic, wood, metal and even fabric! It is a very simple 4-step process (clean, fill, cure and shape) saving countless precious items from ending up in the trash before their time.”

Also mentioned at Gizmodo…

Not A Glue!

Not A Glue!


UPDATE: Apparently this guy’s previous Kickstarter was suspended – so proceed with care…
OTHER UPDATE: Maybe this Kickstarter (Mono) is better. Slicker. Bit more pricey.

This looks like a pretty cool little Kickstarter campaign. An Arduino all wrapped up in a watch-sized unit with a touch screen. And, not too expensive.

I’ve backed it, and we’ll see how it behaves March 2015.

Watch-sized Arduino with touch screen and display

Watch-sized Arduino with touch screen and display


So, yah, crashed my Phantom UAV drone at the cottage a few weeks ago…

It was fairly windy, and my last thought as the Phantom flew by in front of me was “Jeeze, it’s going fast!” – then it disappeared behind a tree, just as I was trying to fly it back out over the lake. But, I reacted too late, and it hit the tree.

The drone ended up in the lake. You can see the underwater video from the unprotected GoPro, and you can hear the sound of the Phantom rebooting a couple of times. Then, it cuts out just as I pulled it from the water.

I immediately took it to the cottage, and put it in the oven at about 120 degrees. Left it there for a few hours.

The next day, I took it for a test flight and everything was fine, except the the video transmitter – which worked, but with a reduced range. Astonishingly, the totally unprotected GoPro was fine!

I’ve flown it a few times since, and it has behaved just fine. Didn’t even have to replace any props!

Note: Loads of water sensing red dye was released inside the Phantom – they must include this in the Phantom so they don’t have to do repairs on water damaged drones. If you’re buying a second-hand Phantom look inside the case for the red dye.


Solid Conference 2014

In May of 2014 I was in San Francisco for the Cisco Live conference. Everything seemed to be going well at our company’s booth, so I ducked out for a day and attended the Solid Conference 2014.

I have to say that it was an amazing experience. I wasn’t expecting much, but within a few minutes of walking in the front door, I was blown away. The speakers (every one of the keynotes!) were simply terrific, and the display area had exhibitor after exhibitor showing things I’d read about in the last year, or seen on Kickstarter. Like the Boston Dynamics Big Dog robot, or the Google Glass booth, or the Form 1 printer, The Lit Motors motorcycle/car, the Taktia handheld CNC machine – and even suppliers like Seeed Studio or Electric Imp who’s stuff I’ve bought.

I’m definitely attending Solid 2015: June 23-25 in San Francisco.

Here’s the URL for the solid conference sessions.

Some sessions worth checking out:

Intelligent machines are different Rodney Brooks

Making Machines that Make Nadya Peek

This lady was terrific. She’s at MIT, and looking into some neat things you can do with modular CNC machines – where you can re-use the CNC machine elements to create different types of machines. Her personal web site is pretty interesting as well.

Google X’s focus on the physical world Astro Teller

Very neat to see what Google is up to and why they do the Google X stuff. They had a glider on display that they plan to use to generate power. It’ll fly itself up, then reverse it’s propellers in order to start generating power. The idea is to get up into the air high enough for there to be steady winds. Neat that the generator planes can fly themselves, and can land, to be easily repaired.

Vision-driven beyond tangible bits Hiroshi Ishii

This guy’s English is not great, but he was brilliant. They could have cancelled the rest of the day just so we could listen to him talk.

Robotics and the natural language of creatives Tobias Kinnebrew

These guys use industrial robots to help create Hollywood films. For example, the special effects in Gravity used these guys.

Beyond Gadgets: Interactive Everything Ivan Poupyrev

Very interesting guy. Lots of different ideas.

Web site hosting with SiteGround.com

I used to use 1and1.com for most of my web site hosting, but the 1&1 plan I’m on (I was a very early adopter of that site) doesn’t really work well for WordPress. Although you can set up a WordPress site – and the even have a really slick tool to do so, the sites fail to upgrade plugins or to upgrade wordpress itself. So, you end up having to do manual upgrades all the time.

So far siteground.com seems to be pretty good. Their support is very good – nice quick answers when I had questions re DNS. And, as part of signing up, they ported over one of my sites for me, which was pretty sweet. The sites come up quickly, and things like upgrades work the way you’d expect.

There are a full suite of tools for easily installing WordPress, Drupal, and a bunch of other things. Nice. And they have pretty good domain management tools.

What I didn’t like was that the first site (the one they ported) was installed at the root of my public html directory, then all the other sites are subdirectories in that same root – so there’s a weird mix of WordPress files and directories, and subdirectories with my other sites. I’d prefer if the “main” site was a sub directory like all the others. Not sure if I can change that.