Posts tagged #cnc

3D Printer Project: Final Assembly & Initial Testing

The last few days I've been going through the last remaining tasks to get the printer running.  First and foremost I finished the wiring.  Because of the dual extruders the number of wires has grown considerably.  The wiring didn't turn out quite as neatly as I'd hoped, but for now it will work.  I've already planned out the cable management for version 2 and it's considerably better than this.

I also built some quick hangers to mount the filament spools on the side.  I plan on replacing these with better versions that have bearings in the near future:

Finally I fabricated a fan shroud to direct air at the hotends correctly.  My initial design for the fan ducts blocked too much of the airflow, so redesigned them to have round openings and pathways.

After testing out various subsystems I was ready to run my first calibration test:

And here's literally the first thing that came out of the machine:

As you can tell from the final part I still have some additional calibration work to do. The extrusion rate, temperatures and z axis all need further calibration.  However I feel this is pretty good first test.





Posted on May 6, 2015 and filed under Projects, CNC Machining, 3D Printers.

CNC Plasma Dinosaur Project

I worked on a quick side project today as a wedding present.  I used my Grunblau CNC to plasma cut a dinosaur and then welded it together with the TIG welder.  It was a good chance to test some changes I made to the packaging of the torch height control electronics and the effectiveness of the water table.

I had some initial issues with the tip plunging into the material, but after replacing the consumables and fiddling with the THC settings a bit it ended up working quite well.  The cuts came out pretty clean:

Also, the water table worked very well for reducing the smoke and fumes.  Moreover the grate is still working well for supporting the pieces.  There is very little cut-through so far and the holes are small enough to prevent parts from falling through.

2015-04-14 12.32.02.jpg

I made a vide of the cutting and welding process:

And the end result turned out well:

Now back to the 3D printer project!








Posted on April 15, 2015 and filed under Projects, CNC Machining.

Open CNC ECU Reference Design

Having worked with a number of CNC devices now (Mills, 3D Printers, Plasma, Laser cutter, etc.) I'm struck at once by how similar the electronics is between the devices, and simultaneously how inefficient/outdated most existing system architectures are.   Most of these systems require there to be a full PC running Windows/Linux attached to each machine, usually with poor network connectivity, and little thought about how to fit the machines together into an efficient unified process.  These factors (and others) make the machines less reliable, more tedious to use, and isolated from the integrated cloud-centric CAD tools becoming prevalent in the rest of the design process. 

Drawing on the strengths of the current trends of tablet-based front-ends and cloud-based data storage, we can begin to establish a newer system architecture that is highly adaptable, flexible, reliable, and efficient. Here is a block diagram of the proposed model:

This system uses three cards for the core of the system:  one embedded CPU card focused on interpreting/running G-Code, one CPU card to act as a gateway to network devices, and one card containing the break out board.  Using a three-board core provides wiring flexibility by allowing the use of different configurations for different machine applications. It also reliably isolates the real-time functions from the non-real-time network interfaces, while minimizing timing critical data paths.  The Network Gateway talks to the front-end GUI via a restful API, thus enabling flexibility on front-end devices (tablets, PCs, etc.), and will include a driver layer for talking directly to a variety of cloud-based storage services (e.g. Dropbox).  Existing front-end software (e.g. Mach3, LinuxCNC) can be used with the system by adding an Ethernet driver that talks the restful API protocol to talk to the back-end.

The advantage of this architecture is that it supports an integrated design process in which designs are developed in the cloud, and then accessed directly on the machine at run-time.  Moreover, a single operator can quickly and efficiently work with multiple machines via a single tablet, switching quickly between machines as they walk around.

In future articles I will begin expanding on each component of the system exploring all aspects of the system, including software, hardware, and packaging.  Furthermore I'm very interested in making this an open standard reference implementation, which standardized interfaces, protocols and connections between each component.  This will encourage a variety of software and hardware development options for each piece, and hopefully encourage a wide range of people/companies to use the system model for their machines.  Feel free to contact me if you're interested in participating in this process.




Posted on April 24, 2014 .