Charles Steinkuehle, the guy behind the Machinekit port of Linux CNC to the Beaglebone microcontroller is going to be in town Thursday 6/26/2014, so we are going to have a special edition of the CNC build club. Special features on the Beaglebone make it the first general use microcontroller to be able to effectively run Linux CNC.
He will be showing off his new CRAMPS (Cape RAMPS) board. This is a cape for the Beaglebone that all all the periferals you would need for a CNC machine or 3D printer
We have featured LinuxCNC on Beaglebone at a few other CNC Build Club events, so it is great to have Charles stop by:
At long last, the CNC Steampunk Harp that Elizabeth and I have been building is, at least functionally, finished! In previous posts, I documented the process of routing pockets in the side of the harp using PS:One’s CNC router, and our road trip to Sector67 in Madison, WI to use their seriously awesome laser cutter. This completed the work on all wooden parts of the harp, and so I could finally assemble it.
First, I had to glue the stiffener boards to the back of the sound board and used the drill press to make holes for the 33 strings. Gluing the sound board to the harp body required a lot of fast work: driving nails to hold the sound board in place, flipping it over and trying to wipe out the dripping glue while only having access to the inside via small holes, flipping it over to drive more nails, rinse, lather, repeat… all the while, the glue is starting to set. Then I glued the trim strips in place that covered all the nails. After that glue dried, I used a 1/4″ roundover bit on a router to clean up the sides of the sound box, and… oops! To my horror, I realized I forgot a step in the directions that said I was supposed to use extra nails to reinforce the area where the sound board joins the base near the pillar. Seeing as the harp has over 1000 lbs tension on the sound board and I really don’t want it pulling itself apart, I used the pneumatic nailer to shoot brads through the lower front trim strip. Then I needed to use wood putty to cover the brads. Oh, and did I mention that the angle of the nail gun wasn’t quite right and the brads poked through the bottom? So I had to bend them over with a nail set and cover those holes as well with wood putty. You live, you learn….
The sound board of the harp had always been the wild card. Elizabeth and I began the project last year knowing that we’d want to use a laser cutter to etch it with some kind of Victorianesque steampunk design involving gears. And we knew that PS:One’s Epilog, with its 24″ x 12″ bed and no feedthrough capability, simply couldn’t fit a 49″ sound board. While design focused on the brass panels, as we did have access to a CNC router, the sound board was left for later, especially because we didn’t know if we could find a smaller laser cutter with feedthrough, meaning we needed a design that could be etched in pieces, or a large laser cutter that could engrave the entire sound board at once.
Elizabeth and I were planning a trip to Madison, WI, and we heard rumors that Sector67 had a colossal Chinese import laser cutter. I reached out to them asking if they would be willing to help with this project, and Chris Meyer, director of Sector 67, responded, inviting us to their space. Knowing what we had to work with, Elizabeth was able to create the design in Adobe Illustrator. Continue reading CNC Steampunk Harp – The Sector67 Field Trip – Part 2→
For the past year, Elizabeth and I have been collaborating on a project using the amazingly cool CNC tools at Pumping Station: One. The goal: to build a harp. Not just any harp, mind you. A steampunk harp! The idea was to start with a kit (the Voyageur harp from Music Makers, 33 strings, cherry) but heavily customize it as follows:
CNC cut brass panel inserts, inlaid in pockets routed in the sides of the harp
The brass panels would be etched using a galvanic etching process, similar to the one used by the Steampunk Workshop to create their clockwork guitar. Elizabeth would design the shape and custom artwork (gears, of course!) for this.
The sound board would be laser engraved with some type of steampunk design. The design is in progress, and we are searching for a laser engraver large enough to handle the sound board.
Although not strictly steampunk, I’d considered adding RGB addressable LED lighting under the neck of the harp, which could illuminate the strings, as well as respond to the pitch of the strings being played.
First, we had to start by routing the brass, using PS:One’s CNC 3020 router. Elizabeth drew the design, including the brass outline and the pattern we will use when we etch the brass. We did this last spring at PS:One, and we ran into massive problems with the brass vibrating and breaking end mills. The project remained dormant for many months until a breakthrough: What if we glued the brass to a scrap board? That would at least keep it immobile so it couldn’t chatter and bind on the end mill. The good news: This worked! Success! The bad news…. The Go To Home button on Mach3 does not, by default, raise the spindle before moving it. And a clamp was in the way. The result: A badly bent spindle. Well, all was not lost…. Continue reading CNC Steampunk Harp – Part 1→
In addition to having Alden Hart talk about the TinyG and motion control in general, Andrew Boggeri of Full Spectrum Laser is going to show off their new sub $2000 SLA resin 3D printer. This is the printer that is currently crushing the goal on Kickstarter.
Stop by and check out the machine and see some of the prints. Resin printers are a little messy to move around so we probably won’t see it print, but plenty of samples will be shown. He will be able to demo the drawing speed, software and cloud interface.
The CNC Club is free and open to members and non members. If you want to attend, please RSVP on Meetup.
Thursday (1/9/2014) night at 7pm we will have an unboxing party for Pumping Station One’s new 3D printer – the Lulzbot Taz 3! The Taz 3 prints larger and faster and in more materials than the other printers we have at the space. Come check out the mysterious BOX, see the printer set up, and maybe we’ll even get to Hello Squirreled.
Also, Ryan Pierce will be presenting “The Hard Knocks School of CNC Milling” covering how he made every mistake possible, and how you can avoid making them yourselves! This will include a lot of useful, practical tips, and a demo of the method he is using, showing the entire tool chain process, to route precisely aligned pockets for his and Elizabeth’s “CNC Steampunk Harp” project
Our shop has a few Black & Decker drills. They’re not contractor grade tools by any means. I was using one the other day for a project, and as I was walking back to the tool crib to put stuff away I was idly clicking the drive direction switch back and forth, as one does with a drill. I heard a snapping noise and the button now moved freely, no longer engaging the electrical switch responsible for direction reversal. Bummer. I figured I’d pop it open and see if I could repair it.
The issue was a small plastic pin that engaged a switch with a matching cutout. Not a very complex mechanism. I drew the part up in Sketchup:
I skipped the nicely radiused leading edge, but this part is otherwise dimensionally similar to the factory piece. My initial attempts to use an entirely 3d-printed part failed, as the ~3mm pin was just not large enough to get a sturdy printed feature. I decided to drill it out and use a #2 screw to replace the pin. This one should outlast the rest of the drill.
At this point you might be wondering why I didn’t do that with the original part to begin with, and that’s valid. My only answer is, “Because I didn’t think of it.”
It’s a simple result, but it’s the sort of thing I love about 3D printing.
Alden Hart, the creator of TinyG and the grblShield will be in town later this month and will give a talk at the 1/23/2014 CNC Build Club @7:00pm. The meeting is open to members and non-members. If you want to attend, please RSVP via Meetup.
The grblShield is a basic stepper motor driver Arduino Uno Shield. It is part of the standard parts list for the Shapeoko and there are thousands of these in the field. It can also act as a shield for the Arduino Due and run a special version of TinyG firmware.
The TinyG project is a multi-axis motion control system. It is designed for CNC applications and other applications that require highly precise motion control. TinyG is meant to be a complete embedded solution for small/medium motor control. Here are some of the main features of the v8 hardware.
Integrated motion control system with embedded microcontroller (Atmel ATxmega192)
4 stepper motor drivers (TI DRV8818) integrated on a ~4 inch square board
Stepper drivers handle 2.5 amps per winding which will handle most motors up thru NEMA23 and some NEMA34 motors
Accepts Gcode from USB port and interprets it locally on the board
6-axis control (XYZ + ABC rotary axes) maps to any 4 motors
Constant jerk acceleration planning (3rd order S curves) for smooth and fast motion transitions
Very smooth step pulse generation using phase-optimized fractional-step DDA running at 50 Khz with very low jitter
Networkable via SPI to support off-board devices and for networking multiple boards into multi-axis systems
Microstepping up to 1/8 (optimized DDA makes this smoother than many 1/16 implementations)
This week we are going to play with the rotary axis on the little CNC mill. We are going to assemble it and calibrate it. We will use a demo of DeskProto to run a job on it. We will of course start with the CNC Ninja Squirrel, then try some other projects. It you have something cool to try, bring a file in STL format and a round piece of material to mill it out of.