I recently inherited a Voron2.4 and I have basic questions

[VoronMoron]

ackground Info:

I recently inherited a Voron 2.4 (my best friend passed away last year and his family wanted me to have it since we shared 3D printing as a common hobby).

I am lost.  All of my other printers (Prusa MK3S+, Elegoo Saturn) are set up to simply print a gcode file that I save onto a USB stick/SD card.  I've never done raspberry pi integration with any of my printers before.

It would seem that the only way to print with the Voron is to use Octoprint, Fluidpi, etc.  I.e. I don't see an SD card slot anywhere...  My friend had his printer set up to use fluidpi.  I have been able to get it connected to my home network (I updated the fluiddpi-wpa-supplicant.txt file with my wifi info, found the ip address, and attempted to ssh connect to the printer.  Big problem - my friend didn't leave his login/password info in his will...so I'm stuck as far as the SSH login goes.

Seeing that, I made a backup copy of everything on the raspberry pi micro sd card and started over (formatted the micro sd and created a fresh fluidpi image using Raspberry Pi Imager).  This allowed me to set up my own login credentials and I was able to SSH to the printer.

After doing all of that, however, I'm getting an error in the fluid Dashboard that says "Unable to open config file /home/pi/klipper_config/printer.cfg."  I don't know what to do with that except continue with the instructions (flash a new firmware version, etc etc.).

What I need help with:

If at all possible, I'd like to simply be able to log in and print something on this printer without undoing the tuning/settings that my friend had in place.  Can I do that without knowing the password for SSH?  If so, how?  If not, is my only option to just treat it like a new build and continue as if I'm starting from scratch?

Any advice appreciated.  And if I said something dumb in this post or it's obvious that I'm making a bad assumption, please slap me (gently) and steer me in the right direction!

Thanks!

Edited June 19, 2022 by VoronMoron

[Todd]

The message you’re getting is more than likely due to a lack of a printer.cfg file. There are lots of them available online. I use Notepad++ to put files where they need to go (ssh them, in other words). I got the same message when I first configured Fluidd. Simply adding the printer.cfg file for the Voron did the trick. I have since moved over to Mainsail and like it much better Thad Fluidd, but to each his own.

[Todd]

Also, make sure you find a printer.cfg file that is written for the mcu(s) you’re running. I have two SKR 2.0 boards and a raspberry pi 3B+ and am totally pleased with how it runs.

[Todd]

If you use a .cfg file for a different board (or boards) the pin connections will probably be different and the results may not be as expected.

[Todd]

Also also….etc.,

look at the stepper motor drivers that are installed. The printer.cfg file may need to be edited to reflect what you actually have.  Pay attention to the commented instructions in the printer.cfg file when it comes to just about everything (thermistors for bed temp, thermistor for hot end, etc. Wouldn’t hurt a thing to double check the settings your friend entered there.

Also, and my sincerest apologies for not stating this up front and before anything, Sorry for the loss of your best friend - those are precious and hard to come by these days.

Let me know if you can’t find what you need to get your new Voron running. I’ll help in any way I can.

 

[ajscheid]

If you made a back up of the previous SD card you should still have the original config files.

Just extract them and upload them via Fluidd and Bob‘s your uncle

[smirk]

6 hours ago, VoronMoron said:

Can I do that without knowing the password for SSH?  If so, how?

You can but it requires a little jiggery pokery, I would also strongly advise making another copy of the original SD card image and working on the copy (of the copy).

However, if you're only after the printers configuration and tunings (assuming you have not changed any of the hardware) then you could as "ajscheid" suggested "extract" them. I'll make an assumption that you have another linux-based machine and clearly you know what you're doing as you'd imaged the original SD card. I'll also assume that the old machine was set up with the standard "pi" user as the default user for the klipper setup.

The klipper configs (along with things like mainsail and moonraker, etc) generally live in the directory "/home/pi/klipper_config" simply copying the contents (printer.cfg, etc) from the original SD card image into the new SD card image should get you all the config and tuning details. When I'm blithely saying copy from one image to another, you need to figure how whether you're mounting the SD card image on some sort of loop-back device on your "other" linux machine or if you're burning them to SD cards and mounting the SD cards to get access to the stuff.

Now having said all that if you are actually after some other elements on the original SD card image, or you're not 100% sure copying the config across will do the job then you can wipe out the password on the old image (with some jiggery pokery). You will need to be able to mount the original SD card image on your "other" Linux machine.

The passwords in *NIX are stored in a file called "/etc/shadow" which is simply a plain text file (that ordinarily is restricted to super-user only access). If you look for that file in your original SD card image, you will need to edit the file as the superuser but, I presume, since you control the "other" linux machine which has the original SD card image mounted, you will be able to use "sudo" or something similar.

Inside the shadow file you are looking for a line that starts with the "pi" user (or whatever the required user id is). For example:

pi:$6$zfCK0GhFAuEor$Ou1paifTdOCVVg6aWO.lz1XOIggHABevMxVyfTbCJTtW00CvsF0HJlQ14x05r/SQJo.ml1umlfPCHSsc6/:19162:0:99999:7:::

That pile of jibberish (in the second field) is actually the encrypted password. SImply deleting that entry will remove the password from the "pi" account, so you end up with something that looks like:

pi::19162:0:99999:7:::

Don't be tempted to simply delete the line as that would remove the password entry entirely and prevent the account from logging in at all. At the very least, deleting the encrypted password entry in the second field,  should allow you to log into the console of the raspberry pi (once you've booted from the doctored image), naturally that requires you to plug a keyboard and mouse in. Once you were logged in you can change the password to something else. If you have no way of using a console then you're going to have to coax SSH into allowing you to log in without a password, which will require you to edit the ssh config file "/etc/ssh/sshd_config" in the  original SD card image.

In the sshd_config file there are a couple of lines you will need to set as follows:

PasswordAuthentication yes
PermitEmptyPasswords yes
UsePAM no

The first line (PasswordAuthentication) will make sure that passwords are being used  (although in our case it's a blank password), SSH can use encryption keys for authentication rather than passwords; the second line (PermitEmptyPasswords) does what it says on the tin and allows you to use no password at all; and the third line tells SSH not to bother using the linux systems pluggable authentication mechanism. Turning off PAM saves you having to muck about trying to figure out how to convince PAM to allow blank passwords and editing yet more config files.

I've just tried this one of my voron's and I can now log in (via SSH) without a password. Clearly of course, undo the changes and set a password once you have access to the system. The other thing I would point out about sshd_config is that those lines (I've listed above) may already exist, perhaps in the opposite settings, so don't just bung those three lines in and hope for the best. Make sure they're they only versions of those lines in the file.

 

Hopefully that will be of some help, but if you need my ramblings explained further then just ask.

 

Edited June 19, 2022 by smirk
correcting grammar

[smirk]

1 minute ago, smirk said:

simply copying the contents (printer.cfg, etc) from the original SD card image into the new SD card image should get you all the config and tuning details.

Just thinking about that rather glib statement - I'm also assuming the versions of klipper, moonraker,etc ,etc are the same. I guess they might not be, so once you have copied the configs overyou could find you need some sort of remedial action to "update" the older versions of the files to something that the newer versions of klipper and moonraker will not complain about.

[okkman]

One suggestion I did  not see mentioned above is to give the default login a try just in case your friend did not change them.  The user is "pi" and the pass is "raspberry".  If that works, you could be in business with a known good config (don't update just yet) and work slowly from there.  If that is a no go, the best idea I saw above is to copy the printer.cfg from the SD card that you pulled out of the raspberry pi.  You will need a machine that reads the linux file system to do so.  There were some major updates to klipper within the past year so updating the config is likely going to be necessary if you are starting with a current image of fluiddpi.

 

Best of luck!

[claudermilk]

First of all, I'm sorry for your loss. It's hard, I know. This printer will be special for you.

Now, to get it working. It sounds like you got a new card set up with Mainsail or Fluidd. All you need are the config files from your backup. Those should be found at /home/pi/klipper_config. There should be at least printer.cfg, moonraker.conf, and mainsail.cfg (or fluidd.cfg) in there. Possibly lots of others. Copy that directory to the same location in the new card and in theory you should be up and running. Worst case, the files are plain text so you can do copy-paste into fresh files.

[VoronMoron]

Wow - thank you all so much for the suggestions!  Looks like I picked the right forum to ask my questions.

When I originally claimed to have made a backup of the original files, I didn't realize that the microSD card had both a Windows partition and a Linux partition.  So, ultimately, I have a backup of the Windows files, but I unknowingly nuked the Linux files when I re-imaged the microSD card.  So that sucks.  Unless someone knows some more amazing jiggery pokery which will allow me to recover these long lost Linux files, I think my only path forward is to start from scratch.

If that's the case, looks like I need to find the right printer.cfg file.  Looking at the physical board, I see that I have a Spider V1.0 MCU.  I've done some googling and haven't found an obvious match for a printer.cfg for that board.  Does anyone have a recommendation for a step-by-step guide for this initial setup?  Looks like I might have to update the printer.cfg (once I find the right one) accordingly with info re: the model of my stepper motors, etc. - I have no idea how to find that kind of info, is it as simple as looking for clues on the physical parts?  or is there a better way to identify the model information of my different components?

[ajscheid]

https://docs.vorondesign.com

and

https://www.klipper3d.org/Overview.html

will be a good place to start.

and the the community on discord is very helpful.

Ask questions here or in Discord if you get stuck. I am sure together we get that baby running again.

 

[Todd]

The Voron discord has some amazing people on it. I’m assuming they’re people, but they could be sentient AIs who really know their stuff for all I know.

[claudermilk]

Yes, the Discord has some very knowledgeable people ready to help. 

For an initial config file, look at this page: https://docs.vorondesign.com/build/software/configuration.html The download link for a V2 with a Spider is about halfway down that first list. Plus there's good instructions on how to start setting it up.

This may be a blessing in disguise, because now you have to go through the config and tuning steps yourself. So you will have an idea what all the stuff means and where to look to tweak or fix something later.