Posts filed under CNC Machining

3D Printer Update

It has been quite a while since I updated this Blog.  I've been working diligently on numerous parts of the printer and I've been able to produce some pretty phenomenal results.  So I thought it was time to provide an update.  I'm going to break the update down into multiple parts to provide a more regular update process going forward.

For this first update I'm going to focus on the CNC machining process for the printer parts.  I've learned an enormous amount about fabricating parts in the last 6 months.  I've also collected a variety of new tools - including an arbor press, 5C collet holder, and a high speed drill.  I've also fabricated new workbenches for assembly and testing:

The first thing I started fabricating was new aluminum parts for the X/Y carriage to replace the 3D printed prototypes.  

After running some test prints I started redesigning the printhead for improved modularity and usability.  It is now clear that a good printhead design is 80% of the value of a precision 3D printer.  I'll go through the various iterations of the printhead in the next blog entry, but in the mean time here's some quick previews:

In November I attended the Houston Makerfaire and had a small booth.  It was a very useful to put everything I had together and practice presenting it to others.  I received some great feedback from numerous people and encouragement to keep going. 

As part of that I created a collage video to show various steps in the fabrication process:

More to come!

 

 

 

 

Posted on January 29, 2016 and filed under 3D Printers, CNC Machining, Projects.

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.

3D Printer Project: Printhead Assembly

The next step in assembling the printer was fabricating the printhead.  The printhead attaches to the X/Y carriage via three alignment pins.  These ensure a perfect alignment and make it easy to switch out multiple types of printheads quickly and easily.  The initial printhead I've fabricated is a dual extruder direct drive configuration.  I also have designs for a single extruder, dual and quad bowden extruders, and others.

The 3D printed version of the base plate that connects the pins and the motor was sufficiently rigid to use for actual run-time testing of the printhead.   On the other hand the plate that holds the hotends to the motors had to be CNC machined to ensure a proper alignment.  This was the first time I was able to use my new Automatic Tool Changer and Tool Height touch-off.  It worked out very well once I figured out the process.

The current printer prototype hands the motors below the XY carriage.  However in the second prototype I plan on flipping this to have the motors on top.  Thus the printhead plates and brackets are designed to be reversible for either configuration:

Motors below:

Motors above:

And since this is the configuration I'm really aiming for I wanted to make sure there was enough clearance for the hotends to pass through the carriage block. Everything looked good.  Obviously the plastic version of the carriage block is only temporary, but even that should be sufficient for some initial testing:

And here's the assembled printhead attached to the carriage in the printer:

I have a few more odds-and-ends to work on and it should be ready for the first test print.

 

Posted on April 22, 2015 and filed under 3D Printers, Projects, CNC Machining.