RepRap has released a new driver board for their stepper motors. They’ve honed the design to be easier to assemble and cheaper. We’re sure all of that is wonderful, but what really got our attention was the video. In the video, which you can see after the break, they run a test file through it to make it “sing” happy birthday. Is this something that everybody does and we’re just now catching on? Why all the musical stepper motors today?
[youtube=http://www.youtube.com/watch?v=uKCX1CeXIjA]
With some careful programming and probably tedious testing, [Tim] was able to get his CNC router to play [Jonathan Coulton’s] “Still Alive”. He didn’t just tell the motors to spin at the correct speeds directly though. He computed the 3d vectors necessary to produce the notes. The router thinks it is just doing its job. We would love to see those vectors rendered out in 3d space. Imagine having a physical sculpture of “Still Alive” as seen by a CNC machine. This reminds us of the Obsolete Technology Band.
[via Skullydazed’s twitter]
The CupCake CNC Kit is the flagship product of MakerBot industries, a joint venture between [Bre Pettis] and [Zach Hoeken]. At $750, it comes with all the motors, belts, body pieces, bearings, belts, and other pieces to assemble it. You could be printing your own 3d objects in a matter of hours with this. 3D printers with only slightly larger capacities can run thousands of dollars. The only advantage to some of the commercial products might be resolution. They don’t give much as far as technical data as the unit isn’t available yet. They should start Shipping before April 15th, so they can’t be far off. This could possibly be a competitor for the RepRap. Since RepRap doesn’t offer a complete kit, we’ll have to speculate. We’ve seen estimates from $500 to $1000 to build one.
[via adafruit industries blog]
Ruin & Wesen are a two person shop creating specialized music gear. As part of their recent MIDI Command development, they got into case manufacturing. They purchased a mini CNC mill to cut the aluminum cases. Unhappy with the software options provide [Wesen] decided to write his own G-code generator. G-code is part of the numerical control used to command CNC machines. He implemented his interpreter using the language he’s most familiar with: Common Lisp (not surprising if you notice the website’s backend). The post covers the design philosophy used and some of the problems that came up. We look forward to future releases since the interpreter can generate milling code using processing.org sketches and cut PCBs directly from Eagle.
You may remember Ruin & Wesen from when they shared their Eagle layout videos.
[Thanks fbz]
[glacialwanderer], who you may remember from his CNC machine build, recently completed an electric spinning wheel. Spinning wheels are used by knitters to turn raw sheep’s wool into yarn. He went through several iterations before arriving at a good design. Besides the motor, there are two major components to the spinning wheel: the flyer and the bobbin. A Scotch tension brake is used to slow the rotation of the bobbin in relation to the flyer. This causes the wool to twist as it’s pulled on.
He initially tried to just use a dimmer switch with an AC motor. That quickly burnt up. The next version used a sewing machine motor since they’re designed with a variable speed control. Unfortunately, it didn’t have enough torque at low speeds. The final design used a DC motor with a SyRen motor controller. It offered plenty of power and at ~$150 it’s still less than the cheapest commercial models on eBay. You can see a video of it and the spinning process embedded below.
Robot Magazine has a great article about how to machine custom robot parts. In this article [Matt Bauer] shows the basics of making custom robot parts and skeletal brackets for his humanoid robot creations using a CNC mini-mill. He uses a custom jig overlay designed to make cutting thin sheet stock much easier and to protect his equipment. This template concept creates a platform for many other custom parts going forward. [Matt] includes the .nc g-code files as well as a “how-to” PDF in a ZIP file.
We’ve been following [glaciawanderer]’s CNC build for quite some time and he’s recently added a few upgrades to make for an even more interesting machine. He’s been trying out new bearing blocks, anti-backlash nuts, and z-axis plates hoping to get some improvements. In the case of the bearing blocks, he went back to the older style because of the added safety and smoother movement. The final addition he made was a dust collection system. It’s just a couple support hoops and duct tape, but it should keep dust out of the threads and rails.
