What’s the state of Octoprint? Any caveats?  

RE: What’s the state of Octoprint? Any caveats?

Posted by: nikolai.r

Posted by: Marcovaldo

=> I was somehow disapointed from the first prints over the RPi:
- Some warping effect and also once had a print loose from Base plate (the standard, not the powder) coated, when printing PLA.
(All test before with MK3S were out of the box top quality and never a fail)
- The print time which showed up on the Octoprint Webinterface was always much shorter (for example 1:50 hrs instead of 2:30)

I read about Octoprint mangling gcodes (yes, it's designed to filter; no it only adds line numbers for error logging...)
But actually (as I was 100% satisfied by printing from SD Card) I do not want Octoprint to do any 'optimisations' as I do not trust any additional 'automatic' intermediate layer (would not trust a self driving car either 🙂   )

This is how rumors are being created...

Again ... Plain Octoprint installation does not mangle or optimize gcode. It's still send the same gcode instructions which are being passed through the USB interface as it would read from sd card. If you want a confirmation and more details, just contact the developer. I'm pretty sure she will be happy to clarify any rumors of this magic black hole "Octoprint". If you don't believe her, then just check the source code. It's open source.

Hi,

Thank you for clarification!

It is difficult to tell rumors from facts, especially if you are new and on google and in the forums are many, many hits on this theme.

I will give it a further try....

Next rumor to debunk: Is there any difference between accessing via USB or via serial connection (like the Pi-Zero does)

Greetings,
M.

RE: What’s the state of Octoprint? Any caveats?

Hi Again,

Just confirmed. - I was totally wrong.

I went through setup described on

all works fine as it should (streaming gcode and RT Webcam connected via USB (Logitech Quickcam Pro 9000 with -r VGA in octoprint.txt)
14% CPU load on a RPi3B

My fault was clicking through during first installation and leaving Temperature for PLA at default.
(at this time I thought the temperature comes with gcode)

Greetings,
M.

RE: What’s the state of Octoprint? Any caveats?

Posted by: nikolai.r

Posted by: Dave

Given this, what gets streamed to the printer from Octoprint has significant differences from what is "raw" in the gcode file, and would be all that's processed by the printer from the SD card.

If you look into the firmware source code, you will see that this data is only being used to store the location in error states. Speculations on bugs in this case is really far catched. 

Careful there, as @david-a66 points out, "actually the N number is also checked to make sure it's greater that the previous line". Checking the firmware source code would show that.

This is not a completely innocuous change... I've had all sorts of problems with Octoprint failing in the middle of a print with the error message that a request to re-send a line fails because it doesn't exist in Octoprint's history buffer (not the exact error message).

So, not too far fetched (which is what I think you were trying to say). I have over 30 years of software development, as an engineer, lead, architect, and then project manager, section manager, R&D manager, and finally finishing my career as COO of a small tech company (I retired early). I have many years of experience with this particular issue (software defects).

As awesome and well-engineered open-source application that Octoprint is (and that's my sincere opinion/evaluation), I can guarantee you there are defects in the code all over the place, most of which have not been discovered, are corner-cases, and might not every be uncovered. But they're there.

Don't ever assume something that seems so simple it can't be a problem (like the line numbers), isn't. You're not omniscient, and as david-a66 demonstrated, you should assume there things you aren't aware of in code you didn't write.

RE: What’s the state of Octoprint? Any caveats?

Posted by: Dave

...

Hello Dave,

I'm also in the software engineering industry for over 20 years now. I know exactly what you're talking about.

This is a support forum and I'm trying to give hints based on what I think helps for the specific case most. I'm pretty sure you did the same because you've experienced issues by using Octopi. 

I'm glad marcovaldo found the root cause and it's working now!

RE: What’s the state of Octoprint? Any caveats?

When I first received my Prusa MK3 I read about Octoprint and wanted the added functionality. Purchased a Pi Zero W, installed it as per instructions from Prusa..... and was immediately disappointed with its performance. It was horrible. Never worked well for me. I then switched to a Toshiba FlashAir SD card which enabled me to send the gcode file directly to the mapped folder on the SD card. It was a challenge getting it setup but once working it worked 99% of the time, but with some really strange problems that I never could explain. But it worked and I used that setup for a year with much satisfaction. I started reading a LOT of messages on the forum about how under powered the Pi Zero was, and how a Pi 3B+ was the much better solution. So I decided to try again, and got a Pi 3B+. Got the official release from the Octoprint site, and with some help watching a video on YouTube titled "Install Octoprint - in 5 minutes - Raspberry Pi - Chris's Basement", I got Octoprint installed and working beautifully. Its connected to the MK3 using USB, and its connected to the network wirelessly. I was thinking that sending the gcode to my Pi 3B+ would be slow, and was going to connect it by Ethernet if it was a problem, but I was surprised to find that transfer speed is excellent, and even better than the Toshiba FlashAir. Never had a transfer error (unlike the Toshiba). Been using it for about 2 months and have to agree with everyone else that you should NOT use a Pi Zero, and get a Pi 3B+ or better. The only thing that I know I lost is the recovery feature when the power goes out, but for me this should be a rare occurrence. I stopped using my Toshiba FlashAir and am now using Octoprint 100% of the time. Haven't seen any issues with print quality or print failures that can be attributed to Octoprint. All my "problems" were with 1st layer calibration, or sending print jobs using a PLA profile when I was printing PETG, and other user errors. 🤔  

RE: What’s the state of Octoprint? Any caveats?

So... Any questions 🙂

My impressions are the same. I wish I'd tried Octoprint first and spent the FlashAir money and time on Octoprint. If you're even slightly unafraid of Linux, there's nothing to it. 

RE: What’s the state of Octoprint? Any caveats?

I started off with OctoPrint and a Pi 3B and have been nothing short of delighted.

I printed my own case which mounts directly to the MK3S frame and holds the Pi and a buck converter.

A Pi camera keeps track of my builds. OctoLapse is great for those impressive videos.

I run directly off the Mk3S psu (not recommended - but I like it).  My LED lighting (printed fixture) runs off it too.

I do have a 350 watt Meanwell PSU waiting - but never felt the need to use it.