OctoPrint issues and tips  

Re: OctoPrint issues and tips

Just an observation as I read these threads: Most USB ports are 2.1 AMPs. The Raspberry 3B+ requries 2.5 amps.

It gets even worse, as "cell phone charger" style USB wall adapters can deliver that amperage at the USB jack. You need 2.5A at the other end of a USB cable. That's why adapters like the CanaKit have an integrated USB cable- they can 'sense' the power drop and compensate.

Something like 20% of Octoprint instances report power issues. It's massively problematic.

Re: OctoPrint issues and tips

Just an observation as I read these threads: Most USB ports are 2.1 AMPs. The Raspberry 3B+ requries 2.5 amps.

It gets even worse, as "cell phone charger" style USB wall adapters can deliver that amperage at the USB jack. You need 2.5A at the other end of a USB cable. That's why adapters like the CanaKit have an integrated USB cable- they can 'sense' the power drop and compensate.

Something like 20% of Octoprint instances report power issues. It's massively problematic.

I just ordered 3 of the Canas

Re: OctoPrint issues and tips

Having a good quality PSU is also important. I've had cheap China PSU connected at first, it's output was 3A, but RPi LCD still constantly showed that green arrow. When i replaced it with original PSU arrow was gone. So, i guess that those cheap PSU's can't cope with sudden power changes, resulting in voltage drop and triggering RPi warning.

Re: OctoPrint issues and tips

Hi everyone,

I've added a Pi Zero by following this guide: https://manual.prusa3d.com/Guide/Einsy-case+with+the+RPi+preparation/840?lang=en

The Pi boots and Octoprint starts, but it won't connect. I am getting the error below:

State: Error: Failed to autodetect serial port, please set it manually.

Can anybody point me in the right direction please?

Re: OctoPrint issues and tips

I get layer shifts when using octoprint. Usually worse the faster it prints. It always happen at the start of a layer. I hear a snap, then it prints with a 0,5-3mm shift. X or Y. Mostly X. Even at the slower quality preset in slic3r, I get shifts. If I down the speed on the dial to 50% it almost never happens.

If I print from SD, I don´t get any shifts at all. Only with octoprint. All belts and gears, bearings are OK. Checked multiple times.

Anyone knows what can cause this?

Re: OctoPrint issues and tips

@magnus.l6

I had issues with layer shifts and Octoprint. Lots of things can cause this, but ultimately it depends on how you have set up octoprint.

1. If you are using a raspberry Pi, have also have set it up with a camera to monitor the prints, do time lapses, then your Pi is skipping (shifting) because it cannot handle all the workload. I resolved this by setting up Pi on an actual server with real server resources and have not had a problem since. The Pi Zero is small, but not very powerful. Use of a camera with it will nearly guarantee issues. Try disconnecting your camera, but make sure you restart your Pi server after disconnecting the camera, or linux probably won't turn off the software that runs the camera...

2. If you are running Octoprint in a VM on your computer, or worse yet running it directly from your computer, while doing other things on said computer, that is likely your problem. You really should totally dedicate a server/VM to Octoprint, and give the server enough resources to not run into issues.

Those are you two likely sources of issues.

Re: OctoPrint issues and tips

@magnus.l6

I had issues with layer shifts and Octoprint. Lots of things can cause this, but ultimately it depends on how you have set up octoprint.

1. If you are using a raspberry Pi, have also have set it up with a camera to monitor the prints, do time lapses, then your Pi is skipping (shifting) because it cannot handle all the workload. I resolved this by setting up Pi on an actual server with real server resources and have not had a problem since. The Pi Zero is small, but not very powerful. Use of a camera with it will nearly guarantee issues. Try disconnecting your camera, but make sure you restart your Pi server after disconnecting the camera, or linux probably won't turn off the software that runs the camera...

2. If you are running Octoprint in a VM on your computer, or worse yet running it directly from your computer, while doing other things on said computer, that is likely your problem. You really should totally dedicate a server/VM to Octoprint, and give the server enough resources to not run into issues.

Those are you two likely sources of issues.

It´s a raspberry pie Zero. Got it just to mointor prints when i´m not at home.
No where have I read that it can mess up your prints. It makes sense though. I have alot of plugins installed. I feel it have gotten worse and worse. Probably because the plugin list has grown over time.
Thanks.

Re: OctoPrint issues and tips

Get yourself RPi3 and you won't have any problems. I dumped zero quite a while ago. I have RPi3 connected via USB and works like a charm. I have 10 inch LCD on it, so it runs desktop also. Zero is indeed way underpowered. I guess it was mentioned here before, but again: even official octoprint site suggests NOT to use zero as server. That's why somehow i don't understand Prusa's decision to use Zero... ok, maybe they expected that people won't use camera. But, to expect that is....like buying a hot air baloon and not fly with it 😆

Re: OctoPrint issues and tips

Get yourself RPi3 and you won't have any problems. I dumped zero quite a while ago. I have RPi3 connected via USB and works like a charm. I have 10 inch LCD on it, so it runs desktop also. Zero is indeed way underpowered. I guess it was mentioned here before, but again: even official octoprint site suggests NOT to use zero as server. That's why somehow i don't understand Prusa's decision to use Zero... ok, maybe they expected that people won't use camera. But, to expect that is....like buying a hot air baloon and not fly with it 😆

Using the camera to remotely monitor and abort failed prints is the biggest reason, at lest for me, to run octoprint.

Re: OctoPrint issues and tips

Log into your pi with putty client and run "top" command. You will see CPU usage. It will be surely constantly at 100%. On my Pi it's way under 50 at full load with camera and desktop running.

Re: OctoPrint issues and tips

If you use "prusaprint" as is, without any or more cpu intersive plugins and no camera, with pi 0 w , using the top command in terminal when printing, max load reaches 40%.. so its doable but don't stretch the pi power

Re: OctoPrint issues and tips

That' true, but what's the point then? Ok, you can see current position of print in %, you can see temperature, but you can't see main thing: check out occasionally if print is ok or something went wrong...

Re: OctoPrint issues and tips

I use it just to remove the hassle to save to a SD card using an adapter , control the printer without a knob, seeing the status of a print without checking the display and other small convenient features like that.
But I'm sure it will work with a camera if you edit the config file for the camera to record at ~5 fps and vga resolution. This setup should not put much strain on the pi.

Re: OctoPrint issues and tips

Has anybody here added a mini LCD screen to their octoprint? I have a 7" touch LCD that I thought would be cool to connect to the Pi via HDMI but I can't get the driver to load apparently. The screen powers up when connected but only flashes and won't display a constant image (nor is the image it does put up octoprint) It's actually a text menu of some kind but it flashes so quickly you can't see it to read any of it.

Re: OctoPrint issues and tips

An HDMI monitor attached to the Pi will just serve as a console display for Raspian/Linux - you won't see what you see in a web browser connected to Octoprint.

Re: OctoPrint issues and tips

An HDMI monitor attached to the Pi will just serve as a console display for Raspian/Linux - you won't see what you see in a web browser connected to Octoprint.

That is not exactly true. You need to install RPi desktop, then If you go into RPi web browser and enter printer IP you will see exactly what you see in a browser on PC (Mac).
You don't need driver, you just have to install desktop via putty command. I have 10 inch touch screen LCD installed and i work mostly with that.

However, it's not reccomended to do that on Zero - it just doesn't have enought power, especially if you have a camera attached, too.

Re: OctoPrint issues and tips

Has anybody here added a mini LCD screen to their octoprint? I have a 7" touch LCD that I thought would be cool to connect to the Pi via HDMI but I can't get the driver to load apparently. The screen powers up when connected but only flashes and won't display a constant image (nor is the image it does put up octoprint) It's actually a text menu of some kind but it flashes so quickly you can't see it to read any of it.

To troubleshoot this:

ssh to the console of the pi. (use putty if running windows on your computer)
In case you need to enable ssh here is the docs: https://www.raspberrypi.org/documentation/remote-access/ssh/

1) Verify that the pi is set to use console mode:
sudo raspi-config -> 3 boot options -> B1 Desktop/CLI -> B1 Console

2) Check the display resolution is set correctly for you screen:
sudo raspi-config -> 7 advanced options -> A5 resolution -> pick the lowest mode that you display supports

3) Reboot the pi: sudo reboot

If this fixes the problem, then go back and change the video resolution to a setting that provides you the best display.

4) If this doesn't fix it you may need need to manually configure the HDMI values vi config.txt.
Here is the link to the documentation for the HDMI settings in config.txt: https://www.raspberrypi.org/documentation/configuration/config-txt/video.md

RE: OctoPrint issues and tips

Posted by: Protoncek

Having a good quality PSU is also important. I've had cheap China PSU connected at first, it's output was 3A, but RPi LCD still constantly showed that green arrow. 

Note that most of the "3A" power supplies I've bought conk out at barely 2A, as measured even by a cheap load tester like https://www.ebay.com.au/itm/282530004049 (which is probably my best /r/unethicallifeprotips, buy one when you need a 2A supply and send a photo proving it can't do 3A and get a refund... )

Hey I did a search but couldn't find a reference to this - I'm getting "Object doesn't fit print volume" errors when loading up objects, about half the time.  There's no part outside the print area, the objects are nowhere near as big as that, and if I go ahead and click "Print" again it works normally. Can't discern a pattern as to what kind of object will trigger this error vs. which ones just print on the first click.

RE: OctoPrint issues and tips

Posted by: bscott

 Hey I did a search but couldn't find a reference to this - I'm getting "Object doesn't fit print volume" errors when loading up objects, about half the time.  There's no part outside the print area, the objects are nowhere near as big as that, and if I go ahead and click "Print" again it works normally. Can't discern a pattern as to what kind of object will trigger this error vs. which ones just print on the first click.

One thing that can cause this is that the gcode produced by PrusaSlicer goes outside the normal build volume when it primes the extruder at the start of a print. You can work around it by going to OctoPrint settings, editing your printer profile, checking "Custom bounding box", and putting a "-3" in the "Min Y Coordinates" box.

RE: OctoPrint issues and tips

It is a beta feature and under development. I have disabled if for now.