Setting up OctoPrint

This post will be a continual scratchpad of info as I use Octoprint…

I’ve toyed around with OctoPrint in the past: Before I built the C-Bot I was seriously considering buying a Type A Machines Series 1 printer: They use OctoPrint, so I’d installed it on a spare Raspberry Pi and played around with it and my Replicator 1.

With the C-Bot, based on its large build size, I want a way to be able to remotely track & control my prints: If I’m not around I can check up on them, pause\stop them if needed in case of failure. OctoPrint is perfect for this. So I decided to finally get it installed and configured on my Raspberry Pi.

Below are the rough steps I went though to make this happen. It’s still not quite ready yet for primetime: I need a way to get the Raspberry Pi & it’s camera to correctly point at the build plate, and a slick case\mount to stick the RPi to the printer (see the next post). But technically I have everything up and running now.

Update: Note that all the trouble I had at any step with the install stemmed in some way from trying to configure wifi successfully: I later switched over to ethernet, and all my problems went away.

My Tech Specs:

Raspberry Pi 2 B
Raspberry Pi Camera
2′ Pi Camera ribbon cable
~~Edimax N150 Wi-Fi Nano USB Adapter~~ : Switched to ethernet.

Setup Process:

Install OctoPi disk image.
- GitHub : Download & install docs I followed. See “Problems Encountered” below….
If you plan on accessing OctoPrint via the web, make sure that “Access Control” is on (which it is by default with any modern install of OctoPi), and you have a valid login. See here. First line of defense keeping people from taking control of your printer remotely.
In your router, give the RPi a static IP. This allows you to log in consistently (locally or remotely), without worrying that your router can dynamically change the IP at some point.
- While it was connected to my router (provided via Comcast), via the router’s control panel, I found and stored it’s MAC address.
- Next I had to make my router “forget” the RPi: For me, I had to first turn off the RPi, then in the router “block” it, then “delete it”.
- With the RPi unconnected, using its MAC address I was able to add it it with a staticIP (My static range was 10.0.0.253+), rather than DHCP.
To allow for remote (web-based) control, in the router control panel, setup port forwarding based on that static IP, for port 80.
To view OctoPrint locally, I can browse directly to the static IP I assigned. Note I was never able to go to hoctopi.local/ either over ethernet of wifi: I get a constant “webpage not available”.
To view Octoprint over the web, I use a search like “what’s my ipv4” to find my homes IPv4 address. Plugging that back into the browser takes me directly to the Octoprint control panel (presuming it’s on).
I have yet to setup a Dynamic DNS service for my IP.
Yet to mess with any of the Haproxy stuff.

Configuring the PiCam:

The defaults for the RaspberyPi Cam appear to be 640×480, I’m not sure of the framerate. That’s a good base starting point, but it can be better.

I edited/boot/octopi.txt to set the res to 1280×720 (720p) at 30fps: The camera tech-specs claim it can do this at 60fps, but I think that’s unnecessary for 3d printing.
In Octoprint, in Settings, under Webcam:
- Set the ‘Timelapse bitrate’ to 10000k, to improve the timelapse movie quality after conversion.
- Set ‘FFMPEG threads’ to 4 (since I have a RPi 2B, that is quad-core) : This will make the timelapse movie creation faster.
Next, I need to get a pair of +2 reading glasses to help bring the focal distance in. Right now it seems to focus best at the rear of my printbed.

Problems Encountered:

I had decided to update my OctoPi image to current since the last install I had done was a good ten months ago:
- After following all the install instructions, I was unable to get wifi working.
- Based on the install instructions (here, under “How To Use It”), they have you modifying the octopi-network.txt file on the SD card: I’m on a Mac, and used TextEdit to do this.
- After three hours of being unable to connect over wifi, I finally dug out my spare monitor and keyboard, so I could log into the RPi directly.
- I used nano to edit octopi-network.txt: To my surprise, the password and ssid values, that should have been surrounded in quotes “”, were instead surrounded by solid white squares: Some weird special character: Changing these to “real quote characters” and rebooting fixed the connection issues. Thanks a lot Apple…
I get terrible camera refresh when connected over wifi: Maybe 1 new frame every… 30 seconds? Unusable. I pay for a smoking hot internet connection, so something is amiss. My google ping is around 900 ms. If I switch over to ethernet the cam us up to 1-5fps (just guessing) and my google ping is 10-20ms: Actually usable. In either case however, the machine control panel is responsive: I’m able to remote control it without much lag. At any rate, I ordered a new wifi adaptor (the one listed above), and I immediately got acceptable refresh: A 1-2 second lag with 5-10fps. Which wifi dongle you get really matters…
- Update: After two days, my new wifi dongle started behaving the exact same: Super slow refresh. I had to drop my capture rate to 3fps, at 640×480 for it to behave. Any faster capture rate would cause increasingly bad lag in the view. So I went out, got a 50′ cat5 cable, switched to ethernet, and problem solved. Super speedy camera refresh. Ethernet FTW.
On a number of occasions the PiCam wouldn’t turn on. Long story short: The 3d printed bracket it fits into was causing the small connector on the front of the cam to actually disconnect from the cam’s PCB.
For the longest time I couldn’t get OctoPrint to shutdown via its ‘System’ menu. All the other buttons worked except those. Long story short: It appaered that having Chrome auto-log me in was causing this: Logging out & logging back in (without ‘remember me’ checked) seems to have fixed it.

…code, cg, electronics, 3d printing…