My OctoPrint (nightmare) Setup

My OctoPrint (nightmare) Setup

While I was digging around for 3D printer stuff I came across OctoPrint (and OctoPi). OctoPrint acts as a print server for your printer. So you don’t have to do the SD card shuffle anymore, or waste a power hungry x86 for the task. My printer is not in the same room as my computers so this works a treat. Also, it allows you to monitor the entire process. It also supports a camera to watch the build. Perfect, I have a RPi camera available. I also found a tutorial to allow OctoPrint to support turning relays off and on to control other stuff (lights, the printer itself, etc…).

(Stay with me, this post is a little erratic)

I followed this and it helped me a lot:

If you have a cheap eBay Raspberry Pi LCD module you will most likely need to go here

For my 3.5″ Inch “RPi LCD” I needed this: wget sudo apt-get update sudo apt-get upgrade  (needed to get 109mb)

Install the driver and it toggles the mode to LCD display: Note: The Raspberry Pi must be connected to the network, or else the touch won’t work properly for some reason.

Your screen should pop on to show the command line, I also got booted from my SSH session, closed by remote host – as the Pi rebooted.

The OctoPi images runs off Jessie Lite, so there is no GUI which fucking sucks, so we need to install one.

Install lightdm (needed 222mb in downloads)

sudo apt-get install lightdm sudo raspi-config

Boot Options > boot go desktop and login as ‘pi’.

Fuck didn’t work.

sudo apt-get install --no-install-recommends xserver-xorg sudo apt-get install --no-install-recommends xinit sudo apt-get install raspberrypi-ui-mods  (needed to get 140mb, 315mb used…Jesus…)

try again to…

sudo apt-get install lightdm

startx without lightdm

no go… Fuck.

startx……ok? tossed errors. Lets reboot. pixman.

./scripts/install-desktop  …. didn’t work either.

Black screen and cursor… ugh damn it all. Nothing but fucking grief… Damn you Jessie Lite, and damn you for removing the GUI guts, and while I’m at it damn you OctoPrint for not having the GUI shit either…

Use the image that works with the screen, that i still have or ? Well the image is Wheezy so shit, nope. Lets try a new install of Raspbian on a SD card, then add the video driver. Will we get a desktop?

So Jessie (full) and lets try the newest drivers for the screen this time?

I finally got it fucking working, and I am not happy that it took this long, and I am not happy with the unit as a whole. Most likely because I m using an RPiB2 maybe? I have also tried a RPiB and that was soooo fucking slow… to the point it was unusable with a touch screen. Might have been ok for just the OctoPrint server but I didn’t even try it I switched back to the B2 immediately.

So… load the OctoPi image (Jessie lite bastards) and once that is done, do the LCD show bullshit… it should reboot and give you a desktop…

Now the god damn camera wont work…I tried the B no go, tried the B2 no go. Tried the B2 again wtf? Oh maybe I should enable the camera via raspi-config?….wtf no where does it mention that, not anywhere… after i found a forum post saying to enable the camera it finally fucking worked…wtf guys.

Now another fucking problem… the browser. Chromium wont load, requires a kernel upgrade or some bullshit… dude wtf, I just downloaded your “complete” image. Complete my ass, I have to do extra shit then it ain’t fucking complete. Epiphany works but no supports for kiosk mode. Jesus…

Is this fucking worth it??

On top of that I hear transferring files via wifi to the SD card is horribly slow. Most people seem to just stick to using the SD card and use the screen on the printer… all for touch control and a camera…gah.

Three fucking days….solid days so far… trying to get this bullshit working.

So to get chromium to work I had to upgrade the kernel, rpi update….

Which broke the fucking LCD screen….fuck this shit. I give up. I’m going back to square one. reflashing the SD card with OctoPi (Jessie lite) enabling the camera and leaving it as touch screen.

I feel depressed now, and lost three days of my life. Dont make the same mistake… or buy an official RPi screen and a new RPi 3. I would actually recommend a 7″, as the 3.5 is way too small. It doesn’t even fill the whole screen.


(Update: this shit was a pain in my ass. I turned out just flashing a straight copy of OctoPi to the card and running it as is. And to correct my mi-information, OctoPrint allows you to transfer files to the Pi or the printer SD card. Going to the Pi is fast, the printers SD card is where it takes FOREVER. Just don’t do it.)


OctoPrint and Email Notifier woes

OctoPrint and Email Notifier woes

I have OctoPrint (via OctoPi) setup and I wanted a way to be notified when my print was done without constantly walking into the garage. So I searched the plugins one day and found the Email Notifier.

After I installed it I could not get it to work for the life of me. I followed the instructions of adding my username and password to the keyring but it always produced an error NameError: global name ‘keyring’ is not defined”. Tried some fixes here and there but nothing had worked. So I bailed.

I tried to install the SMS Notifier (Twilio) instead, and that seems to have broken my plugin installation manager. Great. Now whenever I try to install a plugin after I tried to install the SMS Notifier I get the error message about pip not understanding the output or some shit. Great. I have flashed an SD card 2x and tried this twice, it always causes this issue. Damn you SMS Notifier. I have not looked at their Github for a fix yet, so… (Update: it did not break my plugin manager, that was another issue.)

I went back to the Email Notifier, and this time I got it working. I spent some more time digging on the net and found the solution to the issue I had of the keyring not defined. Then… I ran into a different error of yagmail not wanting to send mail via Google because of some reason (it didn’t say exactly) just gave me the generic error code of “send-mail: Authorization failed 534 5.7.14”. Looking that up had no help. But… I did find the answers to my problems and now my Email Notifier is up and running!

I get the error message of there being a new pip version but I have ignored this so far. These are the steps I took to get it working, YMMV.

First make sure that your Google account is setup to allow less secure sign-ins.

Then SSH into your OctoPrint  and update yagmail then install keyring.

Install yagmail (its probably already installed but hey)

/home/pi/oprint/bin/pip install yagmail[all] --upgrade /home/pi/oprint/bin/pip install keyring --no-deps

Start OctoPrint Python



(control+z to exit)


Reboot the Raspberry Pi for all the changes to take effect. I tried just restarting OctoPrint but that didn’t work. After the reboot I ran into another issue (of course).

“sending failed. Reason :: send() got an unexpected keyword argument “validate_email”

Modify the file (__init.py__ is how it showed on my system with ls ) found in /home/pi/oprint/lib/python2.7/site-packages/octoprint_emailnotifier  and change the line:

mailer.send(to=emails, subject=subject, contents=body, validate_email=False)


mailer.send(to=emails, subject=subject, contents=body)

(here is the fix


Places I found my answers:

I got a 3D printer!!

YES! I finally got one (about a month or two ago), been wanting one for a long time. I did a gig and got some extra funds (mainly, I was able to finally talk the wife into it). So yes, I got a 3D printer!! I did about three days of research and Googling. I had thought I found one and I was about to buy it, then of course, I found another one that caught my eye, it happened to be on sale, so I ended up doing research on that one too. It turned out to be a lot better. Metal body not acrylic. So I ended up with that one. It is a Monoprice Maker Select V2.1, a rebrand of the Wanhao Duplicator i3. A great machine, and very popular which was a factor in my decision. Great community support. Worked great right out of the box, only took about six screws or so to assemble. I did order the MOSFET board to offload the heat bed amperage. Since the board has cheap skinny Chinese traces it is prone to overheat and melt down. I would like to avoid that. The MOSFET does this.

First thing printed…a liver hahah due to my transplant. Then a replacement knob for our Kitchen Aid Mixer. I have tried to print useful things and not dumb trinkets. I don’t want to fill my desk and shelves with plastic knick-knacks. After I printed a few pieces I went straight into printing printer upgrades. The Z-braces were the first thing I printed and it is the best upgrade I have done so far. It shows immediate improvement on your printed items. Of course, now there is a rear Z-brace kit, which I would have done but I do not want to reprint everything and redo the printer. It is solid so as is, so I am leaving it as is.

So far the printer is awesome. I have many plans for it. I  can now print prototypes for my projects and custom boxes for my electronics, this is perfect! I have already started to dabble in creating my own custom “things”.

Using Amazon Polly with Node-Red

Using Amazon Polly with Node-Red

Amazon Polly and Node-Red. This was far easier to get going than any Alexa skill I tried to do. I just came across this the other day on Scargill’s Tech blog.

Amazon Polly is a service that turns text into lifelike speech. … With Amazon Polly, you only pay for the number of characters you convert to speech, and you can save and replay Amazon Polly’s generated speech.”

Basically you feed Polly SSML text and it returns it in spoken form as an MP3 (or other format). Sweet, I can give my server/Node-Red a voice! Not sure my wife will like this but it will actually server a valid purpose. I was admitted to the hospital (again) for a short three-day stay recently and while I was admitted (and loaded up on drugs) my server closet reached my maximum set temperature… and issued the text alert 187 times. Now I can have the server annunciate that the closet needs to be opened. I could add my wife’s number to the SMS list but that will fail, lol. Simply saving the MP3 on the server and having it be played back works just great.

I am sure you can tap into the API many other ways, and use Polly many other ways, but the simplest way was my path. I just logged into the Amazon Polly Developer console and slapped some text in the input box. It spit out an MP3 and I saved it. The catch here is that the free tier of the Polly program only lasts 12 months, then you get charged. Its super cheap though, $4 per 1 million characters. The free tier is 4 million per month (for 12 months). From what I have read Polly will search the cloud to see if the file already exists. If it does it pulls it down, if it doesn’t it creates it (and counts agains the character limit) and pulls it down. Is this for “the cloud” or your account? Dunno. Still pretty cheap.

I have circumvented the whole thing (for now). I don’t really plan on (or have the need to) generating Polly files on the fly. What works for me is as I said, just slapping a ton of phrases I think I’ll need into Polly and saving the files for later. I’m cool with that.

But, there is a node for NR that will generate Polly files for you on the fly, and/or pull down the ones already generated. I mentioned I found Polly on Scargill’s blog, he also used NR to play with Polly. He had to do it the hard way. Three days ago the node was made. Definitely check out his blog even if you just use the node. Its all good info.

Install node-red-contrib-polly-tts

npm install node-red-contrib-polly-tts

The node looks pretty simply to use (I have not used it). You need to add your Amazon Polly API credentials to the node. The input gets TTS’d and the file saved. If the text has already been converted no Polly call is made and just the file served. So it looks like it stores all the Polly MP3s for you locally. Sweet.


Custom Alexa Node-Red Skill

Custom Alexa Node-Red Skill

Finally! I am surprised it didn’t even take as long as it usually does for me to figure shit out. Took a few weeks. As usual, I did not come up with the solution on my own but found it out on the web and slapped it all together. I wanted a custom Alexa Node-Red skill, to be able to take a command given to Alexa and read back data from one of my sensors. Things like temperature sensors, water level, etc. I wanted to be able to ask Alexa what the values are. What I got: exactly what I wanted. It all works. There is two parts to this: the Node-Red flow and the Alexa skill.

Alexa Node-Red

First off, to get any of this working you must have your Node-Red server accessible from the outside world. That means port-forwarding, DNS, domains, SSL, all that. It’s fun getting it all working. Not. Just like my previous post, I happened to have it already setup. Once your Node-Red install is available from the web you are good to go. Now you don’t need the entire NR setup opened up either. I just allowed a few NR served pages to be available. Not the entire NR itself.

Update: I made a new post about Node-Red behind a reverse-proxy/SSL

Let’s Begin

It starts with a regular HTTP node to a switch node. That switch node splits up Alexa’s requests to NR; LaunchRequest, IntentRequest, SessionEndedRequest. LaunchRequest gets invoked when the skill starts. You could have Alexa say “Hello what do you want?” for example. IntentRequest is the goods. Then theres SessionEndedRequest, I’m assuming this gets called at the end. Haven’t toyed with it. Then you pass those requests off to do other stuff, like the DoCommand where it grabs your intent? Then a function node to extract the commands, which gets passed off to another switch node to split up the possible commands you can give Alexa. Give her as many commands as you want, then there is a “device doesn’t exist” at the bottom. This is used if she didn’t hear you right or the device doesn’t exist. All that data gets passed to a template to format what Alexa will say and sticks the data in JSON. Bam! That wasn’t so hard right?

Here’s the flow (all standard nodes):

That’s the Node-Red half. You are not done yet. On to the Alexa skills half. This part is easy don’t worry. Login to your Amazon Dashboard and click Alexa. Choose “Get Started” with the Alexa Skills Kit, click add a new skill. Under Skill Information give it a name and choose the invocation word, what you will say to Alexa to start your skill. I chose “Node Red”, so I have to say “Alexa, ask Node Red….”. These can be changed at any time it seems. You won’t be publishing this skill, it stays beta for only you to use. For the Global Fields section, no you will not be using an audio player. Well, maybe you will but I didn’t, and it will probably change things for you.

Note about the flow: The NR flow works (for me) just fine however I noticed it throws an error in the debug tab whenever a command is called. If it is an unrecognized command response it doesn’t throw the error though. It complains about headers already being sent. I will update the flow if I find a fix for it.

Interaction Model

Intent Schema

Intent Schema

This is the part of the Alexa skill where you tell it what to do. It is pretty straight forward. Just copy this to your “Intent Schema”. There are no custom slot types and no values to enter.

Sample Utterances

Sample Utterances

This is where you list the invocation phrases that will activate Alexa. Normally (and in other online tutorials for Alexa skills) this is where you add a ton of different phrases. But we are not. Node-Red is going to handle that side for us. This box just gets one line of text.


Global Fields/Endpoint

For a service endpoint you are going to pick “HTTPS”. In a lot of other tutorials you will usually choose AWS Lambda but we are doing all of our own heavy lifting with NR. We don’t need no stinking Lambda. Choose your closest location and enter the URL that your Node-Red is accessible from (via the web remember). Say no to account linking and you can also leave Permissions alone.

SSL Certificate

Certificate for Endpoint

Choose the option that bests describes you. Most likely it will be the first option. For me I am using a subdomain that is already SSL’d with Let’s Encrypt so I choose the second option.


Basically just leave the toggle flipped to enable the skill for you to use. you don’t need to do anything else on this page.

Publishing Information

Nothing to do here, you won’t be publishing this skill. Why? Because it requires too much setup on the users behalf. I don’t think Amazon would approve a half functioning skill that requires advanced user setup to get working. You could always try. Good luck.

Privacy & Compliance

Three no’s and one box to check, I mean as long as it all applies to you right 😉


That should be it. With Node-Red available to the web and the flow implimented and with the new Alexa skill you just made you should be good to. I hope you found this useful, I sure wish I had found a blog post like this. Now go test it out with your Amazon Echo/Dot!

At the time of this writing a beta product appeared in the Amazon Dashboard for a the “Skill Builder”, looks to be a new UI for building Alexa skills. If this gets implemented for everyone in the future things may be different than they are described in this blog post.

This is where I found the goodness, buried deep in comments on a (awesome) blog.