Running my makerbot over serial can be problematic because I have an aged laptop. I’m still using an old laptop I scavenged when IT was giving away tired machines. It has a Core 2 Duo at 2Ghz, a 40GB hard drive and 3GB RAM (32 bit OS). It’s still kicking, and can usually do what I need without too much hassle. Recently though, The act of switching windows during a print caused the serial buffer to run out, and the printer would sit for 30 seconds oozing while it waited for more data.
Enter OctoPrint. I recently got a Raspberry Pi model B for a larger PCB design project I was planning, but that is temporarily on hold. I did some reading about what I could do with it, and was torn between a pandora interface for the stereo downstairs, and a mini-host for the 3D printer. Once the printing problems surfaced, it sealed the deal.
A little bit of poking (following instructions from the premade OctoPi package) later, and I had it communicating with my customized Ramps-like electronics running Marlin. I did add a USB port to the 5V line of the printer power supply, so I can use a small USB cable to power the Pi. I rearranged where the boards were located on the side of the box, and wired it all up. It turns out the ‘mounting holes’ in the Pi can be tapped for M3.
The normal FTDI cable runs the serial interface, and I plug into the ethernet jack on the Pi to get the web interface.
I did have to poke at the mjpg_streamer settings to get it to talk to my cheap webcam, but I published the settings to the Octoprint Wiki for others to use.
I have a monoprice order coming in next week, and that includes a USB wifi widget that reportedly works with the Pi, so it will be completely wireless! I had to dig out a wifi-bridge to get some ethernet jacks on my desk for the Pi to plug into for now.
I also have been playing with print settings, pushing the limits on layer thickness. The video above is thing 1842 being printed with 250 micron layer height. The blurry shots in the video are the webcam contstantly refocusing trying to keep up with the printer. The screenshot of the interface is the same part with a 150 micron layer height (300 micron infill). Not bad for a 2010 Cupcake (Though the only original electronics are the power supply and the motors).