HOW TO: Multiple 3D Printers Using OctoPrint 2019 – Raspberry Pi and Ender 3 Step by Step

OctoPrint is a great project for setting up 3D printers to control from a web based interface. Even when only using a single printer, the advantage to connecting a Raspberry Pi to your 3D printers is amazing:

  • Great UI to see your printer and it’s status
  • Allows you to connect to web cams to see progress, locally and remotely
  • A bunch of great plugins to control and monitor your printers – do fun stuff like post updates to a slack channel to keep track of prints and so much more
  • Drag files to print to the web interface instead of messing around with SD cards
  • Easily view print status, cancel prints, organize your upcoming prints
  • Check and modify temperatures, flow rate, feed rate, motors and fans
  • Issue GCode directly to the printer
  • Update the firmware of your 3D printer, directly from the OctoPrint interface
  • Learn a little Linux, and do that Raspberry Pi build you have been thinking about

Here is a step by step guide to get you up and running on OctoPrint using multiple 3D printers:

  1. Install OctoPrint
    1. Download the latest image found HERE
    2. Burn the image to an SD card using ETCHER
    3. Install PUTTY or use another SSH client (your OS may have one)
    4. Insert the SD in your Raspberry Pi, and power it up!
    5. Connect to the Pi using Putty – you may need to figure out it’s IP using your router admin interface
      1. PROTIP: Optional – configure your router to give the MAC ID or your Pi a static address and/or name to make it easier to connect in the future
    6. Follow the instruction above with one printer connected and verify that OctoPrint can control your first printer
      1. PROTIP: Get comfortable with OctoPrint first, use it for a print or two if this is your first time, as some things will make more sense later
      2. PROTIP: Install some plugins before copying below, in some cases this will make things easier down the road
      3. PROTIP: When you are done and happy with a single printer, create a backup in OctoPrint, and download it to your PC just in case
  2. Out of the box, OctoPrint can connect to multiple printers, but not to control them all at once – so we need to login to the Pi and get started copying some files and change some things to get new instances of OctoPrint running for each of your printers. The following details show 2 printers being connected, it certainly works for 3 or more – up to the performance limitations of your Pi – mileage may vary, but 3 works without a hitch for me
    1. Copy the OctoPrint directory
      1. cp -R /home/pi/.octoprint /home/pi/.octoprint2
    2. Copy the config script
      1. sudo cp /etc/default/octoprint /etc/default/octoprint2
    3. Modify the config script
      1. sudo nano /etc/default/octoprint2
        1. PROTIP: Ctrl-X to save when you are done in nano, Y to confirm, enter to confirm file name
    4. And change the port and arguments  to look like the 2 lines below (leave the “DAEMON=” line as it is, it is used by each of the new Octo-instances)
      1. PORT=5001
        DAEMON_ARGS="--port=5001 --config home/pi/.octoprint2/config.yaml --basedir /home/pi/.octoprint2"
    5. Copy the init Script
      1. sudo cp /etc/init.d/octoprint /etc/init.d/octoprint2
    6. Modify the init Script
      1. sudo nano /etc/init.d/octoprint2
    7. Change everything here to be octoprint2 (EXCEPT the DAEMON= line again) and save it like so:
      1. #!/bin/sh### BEGIN INIT INFO
        # Provides: octoprint2
        # Required-Start: $local_fs networking
        # Required-Stop:
        # Should-Start:
        # Should-Stop:
        # Default-Start: 2 3 4 5
        # Default-Stop: 0 1 6
        # Short-Description: OctoPrint2 daemon
        # Description: Starts the OctoPrint2 daemon with the user specified in
        # /etc/default/octoprint2.
        ### END INIT INFO# Author: Sami OlmariPATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
        DESC="OctoPrint2 Daemon"
    8. Reload the init script
      1. sudo systemctl daemon-reload
    9. Let’s make it start every time automatically after booting
      1. sudo update-rc.d octoprint2 defaults
    10. Without a reboot you can just start it now
      1. sudo /etc/init.d/octoprint2 start
    11. And check the status like so:
      1. systemctl status octoprint2.service

That’s it! You should be able to log into your OctoPrint service on your Pi now via a remote browser from your PC. If the original (use the ip you determined before) was using the default port, you connected like this
And now your new printer should be ready to go on port 5001 like this:

Remember, the IP address above is an example, you need to figure out what IP your Pi received on your network.

OK, bonus time now, this is optional, but makes things handy in the OctoPrint UI to figure out which printer is connected to which USB port. When the Pi boots, for example, USB0 may be assigned to printer 1, but next time to Printer 2 – so lets create some settings that make it easier to figure that out in OctoPrint.

  1. Use Putty, or whatever, to get connected again if you are not already there to the Pi
  2. Plug your printers in and fire them up
  3. Check out your udev info to figure out some of the differences between the connected devices to make some changes later. Here, for example, we can take a look at USB0:
    1. udevadm info -q all -n /dev/ttyUSB0 --attribute-walk
  4. Then, for example, take a look at USB1:
    1. udevadm info -q all -n /dev/ttyUSB1 --attribute-walk
  5. These commands will spill a bunch of info that you will need to differentiate each connection, my file below is just an example, but usually you can use the “idVendor” and “idProduct” and “devPath” attributes as the differences.
  6. Look at the first section with these attributes for EACH of these commands and make note of the attribute values for the 2 commands. If at least ONE of the 3 is different from the other 3, you are good to go and use the example below. If they are the same, you need to look through the attributes to fine ones that differ and include those
  7. OPTIONALLY – if you are familiar with “diff” you can pipe the commands to files, then use diff to show the differences and use it’s output to figure out what attributes you will use in our rules file below like this:
    1. udevadm info -a -n /dev/ttyUSB0 > devInfoUSB0
      udevadm info -a -n /dev/ttyUSB1 > devInfoUSB1
      diff -u devInfoUSB0 devInfoUSB1
  8. OK. Almost there. Lets create some rules! Now we just need to create symlinks to those attributes to some names that we can see in OctoPrint to make it easy to figure out what the heck we are connecting to. On the Pi, lets do this:
      1. cd /etc/udev/rules.d/
        sudo nano 99-usb.rules
  9. And paste/enter something like this in the file, ctrl-x to save again like above (remember, these are MY settings – use your attributes and values that we figured out above – there should be 3 lines in the file, the 3rd is an EXAMPLE for a 3rd printer, so if you are just doing 2, there should be something close to the first 2 lines): I have 3 printers here, I called them ttyEnder3_1, ttyEnder3_2, and ttyMonoMini. Name yours whatever makes sense to you for your printer types.

    1. SUBSYSTEM=="tty", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", ATTRS{devpath}=="1.1.3", SYMLINK+="ttyENDER3_2"
      SUBSYSTEM=="tty", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", ATTRS{devpath}=="1.3", SYMLINK+="ttyENDER3_1"
      SUBSYSTEM=="tty", ATTRS{idVendor}=="2974", ATTRS{idProduct}=="0503", ATTRS{devpath}=="1.1.2", SYMLINK+="ttyMonoMini"
  10. BONUS: Set your timezone if you haven’t already on the Pi before we reboot and take a look:
      1. cp /usr/share/zoneinfo/America/Chicago /etc/localtime
      2. OR like this:
      3. ln -s /usr/share/zoneinfo/America/Chicago /etc/localtime
  11. Either way you set that, if you are unsure of the zone, type up to the point you need to change it, and hit tab a couple of times for your options… So typing this:
    1. cp /usr/share/zoneinfo/
      will display this
      Africa/ CET Etc/ Greenwich Japan Navajo PST8PDT US/
      America/ Chile/ Europe/ Hongkong Kwajalein NZ right/ UTC
      Antarctica/ CST6CDT Factory HST leap-seconds.list NZ-CHAT ROC WET
      Arctic/ Cuba GB Iceland Libya Pacific/ ROK W-SU
      Asia/ EET GB-Eire Indian/ localtime Poland Singapore
      Atlantic/ Egypt GMT Iran MET Portugal SystemV/
      Australia/ Eire GMT0 Mexico/ posix/ Turkey Zulu
      Brazil/ EST GMT-0 Israel MST posixrules UCT
      Canada/ EST5EDT GMT+0 Jamaica MST7MDT PRC Universal
      And the same goes for the rest of the command to get yours right.
  12. Lets reboot, and browse to your URL’s again above, and configure each one to find the new device names in the serial settings.
    1. Click the Wrench icon in OctoPrint
    2. You should be in Printer->Serial Connection->General
    3. In the Additional Serial Ports box, lets add some rules to pick up the new device links, mine looks like this: 

Hit save, refresh your browser, and you should have new, way better names in your connection drop-down like this to differentiate your connections:

And that is it! I hope you find this helpful, let me know in the comments below if there are missing steps, or if you have better/other ways of doing some of the things here. Happy Printing!

Should I Buy a Curved Monitor

I recently had that question, and came up with the answer – Sure! In fact, I jumped in and bought 2. Was it a good decision? Is it better than a traditional flat screen setup? Does it make sense for anything other than gaming? What about the cost? Here are a a few thoughts on the subject, and a link to the monitors that I went with:

First of all I was surprised that the price for a set of curved monitors was so low. Sure the Samsung LC24F ones that I picked up aren’t the top of the line, but they are really nice for the price. I added 2, sitting on monitor stands at just under eye-height. At first, there is something strange about curved monitors, something that you notice standing up and looking at them way more than when seated in front of them. These monitors look great in the space and add a nice futuristic look to the setup.

So what about in real-world everyday use? The odd thing about good curved monitors is that you don’t even notice. The content on screen sort of wraps into your peripheral vision and makes it easier for you to slightly turn and look at the content, but you really don’t notice the curve at all. Only when you think about it or stand up do you see the curve again.

I would definitely make this upgrade again, in fact I am thinking about adding a 3rd, and may even mount it above the 2 in place now. I have things that I like to monitor, but don’t really interact with that would be nice to display on another monitor while using the 2 below for everyday dragging and dropping windows around for productivity. The mounts on these monitors come right off, and they have the standard mounting hardware on the back to make things easy.

Now if I could just get my employer on board, and get a few of these in my work station… Until then, I’m enjoying the switch to curved and think you should give it a shot too! What is your experience? Share below!

Sonos – No Google Home Automation in 2018

And just following a post on the subject, Sonos is looking to testers across the web to sign up for their Google Home automation support, promised in 2018, but not happening. In the request for beta testers, they state that their is no dice on Google Home Assistant integration in 2018 as they had previously stated in announcements earlier this year. Provided all that testing works out, we can now sit tight and expect them to get this out, wait for it, in the future.

Well, is 2019 Google Home Assistant Sonos integration coming??? You make the call in the comments below.

Google Assistant Home Sonos Automation Where are You?

Earlier this year, Sonos proclaimed that their awesome network-powered in home speaker system would provide support for Google Home Assistant automation in 2018. They went so far as to shake up the executive team, and provided statements about how they were all-in getting the ecosystems available for Google Home.

Well here we are in the final days of 2018, counting down the moments that will lead us to the inevitable fail, and without really a peep from Sonos or their all-in strategy. Sure they made some strides with Alexa and Spotify integration along the way, but Google Home Assistant is still the red-headed step child of home automation.

Too bad those expensive Sonos speakers sit waiting for something to happen in this space, because they are still the kid to beat when it comes to awesome sound and seamless integration into home and home theater solutions. But the clock is ticking. If another vendor steps up and provides products that match the quality of the Sonos line, there will certainly be a bunch of people who abandon ship in the space, and you will see a huge bump in Sonos speakers and gear hitting eBay moments later. When this happens, Sonos will be dead in the water instead of being positioned as the solution of choice on high end speakers as they have been in the past. Add the possibility of a spry Anker or other vendor jumping in (sure Google has the Home Max, but meh), providing quality and integration at a low price and the Sonos dream will be over.

I currently have 9 Sonos speakers around the house, and would certainly love to see the product move forward in the Google Assistant space, so sure I have a horse in the race. But couple the lack of integration and the awful change when the Spotify API changed and the Sonos app no longer maintained the folders, groups, etc. and the writing may finally be on the wall.

Drop your thoughts in the comments below, we would love to hear about your solutions and thoughts for the Sonos/Google Assistant world…

Android Grocery Shopping List App ToMarket Updated

After some time, the Android Grocery Shopping List app ToMarket has been updated. Check out the app in the Google Play Store right HERE

You can also check out the website over at the official site:

Here is a short list of the features:

  • Enhanced voice features – move a list of items to your need list all at once and much, much more!
  • Convert HandyShopper Files – Use our new ToMarketHSConverter to convert your HandyShopper.pdb files into ToMarket files.
  • Purchase History – Record your purchase history for checking date, store and cost of previous purchases.
  • Per Store Aisles – Associate unique aisles with each store.
  • Fully Customizable – Choose which features to use, which items to display.
  • Bar Code Scanning – Add items to list by scanning the barcode, once in the list scan to move it to need or cart.
  • Voice Recognition – Search for items on your list and easily move it to need or cart.
  • Email or Text – Use email or text to share your list with someone else.
  • Coupons – Track which items you have coupons for.
  • Price Your List – Save money by tracking the cost of all items on your need list or in your cart.
  • Import/Export Data – Easily export and import your data to and from your SD card.
  • Modify CSV List – Copy export file from your SD card to your computer, make edits and then import back into ToMarket on your Android device.
  • Create Multiple Lists – Stay organized with lists for everything you need: groceries, movies, wine, tasks, books, gifts, etc.


How do I know if Netflix is streaming Ultra 4K HD

  1. Search for Test Pattern on Netflix.
  2. Let the test you want the results of run, and the results will be in the upper right corner though it takes awhile to stabilize. It has a test for everything. There are a few to test 4k capability.
  3. Also, the 4k banner should appear when it plays 4k content and only the highest priced plan has it though currently there aren’t many shows in 4k.
  4. Also be sure to enable HDR on your TV. I know I’m watching 4k when it switches to the HDR mode on my LG.

Top 10 Reasons You Should NOT Sell on Ebay

Selling on eBay seems tempting when you have some miscellaneous stuff to get rid of, or you have an idea to become a seller with a store to strike it rich in the e-commerce world. The thought of selling without a store-front from the safety and comfort of your home is enticing, but the perils are huge for sellers, and the risk of selling on eBay is huge – and in my opinion there are a bunch of reasons to stay away, and look into other opportunities to sell your stuff. Here is a list or reasons why you should NOT sell on eBay:

  1. The Fees

    Start with the fees. This is an easy one going in, as you can read about the fees and understand them before you get started. They will get you started with FREE insertion fees, but take a look at the cut that they receive for every item – it’s huge, and if you are operating on a slim margin, the rest of this list will ruin your chances of making it big.

  2. The Buyer Protection Policy

    The Buyer Protection Policy will be your worst enemy. It says basically that “go ahead and buy, no matter what happens we will refund you if you like for any reason whatsoever”. As a seller this means they can claim it was dusty, the wrong shade of pink, whatever. The buyer can simply say they didn’t get it, whether they did or not, and your funds will be frozen, and eventually given back – it doesn’t matter how careful you are with tracking information, packing, shipping, nothing. This is probably #1.

  3. The Scammers

    Scammers will come at you from all angles. New accounts, people trying to make you ship it to another address, payment on the side offers, you name it, there are too many to even list how they will try to fraudulently get your item.

  4. The eBay Site Deliberately Hides Stuff From Sellers

    Someone complains? Want to see the listing from their message? Nope. Says the item was never received? How about finding your tracking from the message? Nope. eBay makes it aggravatingly hard to find the details of your listing when there is a problem. Want to find out what the buyers rating looks like when you get a message with a problem, lol, have fun finding it. You won’t get to it from any of the details of the messages received about the buyer about to get their money back. There are so many times you will run into this and think “This is a stacked deck in the buyers favor” which leads us to:

  5. The Buyer ALWAYS Wins

    If the buyer has any problem, real or delusional, they win. You will lose.

  6. The Buyers Think You Are Amazon

    So with all this protection, the buyers get to purchase items from you with complete protection and they act like you are Amazon. Free returns! Free protection! Free disputes in their favor! They will say the item is scratched on that one of a kind item you sold them and request a replacement. They will complain when the item takes 4 days to get to them. You are going to hate this one…

  7. The Listing Terms You Specify are a Joke

    So you set a listing up with no returns, item as is, describe it perfectly, tell your potential buyer that it’s a crumbled pile of dust and they purchase it anyway. Well guess what, whatever you say in the listing is a waste of time. Don’t even type it for all that it matters. Sure some people will read it and understand the shape of the item you are selling but guess what: SEE #5 and #6. It doesn’t matter. They will get a refund.

  8. More Fees for Payments

    So start a store, and you can pay eBay monthly for their awesome (lol) storefront service and save a boatload. Well with all of the deck stacked in favor of the buyer, and the losses you are about to receive from those purchases, it does help but only if you have some serious volume. This will bite the person selling a few items here and there, and the storefront will just be another fee eating away at your profit. More fees? Yep, pretty much the only way to be successful is to use PayPal and they will take a huge chunk too. I won’t even go into detailing all of the fees that will be charged for eBay and PayPal – they probably went up last night anyway.

  9. eBay Forces You to Add Details You Don’t Want

    List an item and off you go right? Nope, eBay may force you to add details (presumably to increase the search results to your item) but force you to add details that you may not want added. Sure, decline and your items will be removed from your listings.

  10. You are Going to get Ripped Off

    Add all of these up, and YOU WILL GET RIPPED OFF. Maybe all of the fees (oh and the manual process to get your sellers fee back when something goes wrong) won’t deter you, but there are just way too many ways for the eBay system to work against the buyer and you will lose. Just when you think your listings are going great, and you have accepted the fees and are happy with buyers you are getting, boom. Everything will crumble and the only people left happy will be your buyers and the eBay shareholders. You will eventually be robbed by the system, and they don’t care because it’s set up to make happy buyers and slice huge chunks of money from every transaction – regardless of how well a seller behave in the system.

    So there you have it, I could actually go on with more and more items to think about when you sell on eBay, and in my opinion, the risk just isn’t worth it. When you add it all up, the potential for you coming out ahead is about as good as a dicey Craiglist transaction in a dark alley late at night. You might get paid, but you might…

What is your experience using eBay as a buyer or seller? Leave me a note below!

Google Home Assistant Easy Garage Door Home Automation

This is an easy way to add home automation to your existing garage door with a pretty simple, cheap, and quick to install device.

The first thing you will need is one of these MHCOZY WiFi devices.

When you get it, just follow the steps here:

  1. Install the eWeLink app from the Google Store
  2. Add a USB power cable to the device (NOT INCLUDED WITH THE DEVICE – you probably have some already, they are just micro usb)
  3. Power up the device, and follow the instructions to pair it to the device
  4. You will need the wifi password
  5. You may need to turn off 5Ghz mode on your router if the app complains about only being able to use 2.4Ghz (you can turn it back on after the pairing witout issues)
  6. You will need to press the pairing button on the device (the one that is lit) for a few seconds to get it into pairing mode
  7. When this is complete, you should be able to use the eWeLink App to hit turn on (there is only “On” when it comes to circuits of this type – it’s just a button push, and as with your garage door opener device, it is not aware of open and closed, so on is open, and on is closed)
  8. Now head into Google Home and add a previously configured device
  9. IMPORTANT – in order to avoid confusion READ THIS – the app to link in Google Home is called “Smart We Link” (thanks for naming it something else eWeLink folks 🙁  )
  10. Now the device should click when you hit open, via the app or by talking to Google Home (using the device name you used during app install or Home alias name)
  11. Next, unplug the device and head to the garage
  12. Wire the device to your garage door, and into the Common (center) and Normally Open (labeled NO on the back of the device) connector. I had a striped wire going to the garage opener from the wall switch (which I left in place, I just added another set of wires to those terminals) so I ran that striped into the NO and the white wire into the Common.
  13. I mounted the device to the 2×4 on the ceiling, powered up, and BOOM – the app and google home now control the garage for about 15 bucks US

Hope this helps if you are looking into a garage door home automation solution. You can use this little device to do other things (and I just ordered another so hold on tight) like powering on a PC, and controlling gates, lights with an add-in circuit board etc. Let me know in the comments if you have any questions or other uses.