Wednesday, October 16, 2024

Minimizing/removing wipetower

 Putting this here for reference - a thorough example of making wipe objects and not needing a purge tower in Bambu studio.

https://forum.bambulab.com/t/making-better-use-of-flush-into-object-in-bambu-studio/29422


Referenced from https://www.reddit.com/r/3Dprinting/s/XGbFlV9CtS

Tuesday, October 8, 2024

Wipetower tempature fix when using multiple materials with the MMU

 Due to a bug (with a longstanding, updated PR) on the temp change happening after a filament swap instead of before it causing clogs when higher temp filament hits a cold nozzle, coupled with the difficulty building PrusaSlicer yourself, they've started pushing up their own builds/releases on their fork of Prusaslicer - lets hope that this PR gets merged into core soon so this workaround isn't required!


https://github.com/amatulic/PrusaSlicer/releases/tag/wipetower

MMU3 Gotcha with Octoprint!

 When setting up the MMU3, I forgot to (didn't realize that I need to) configure octoprint to see that my printer had more tools, so it was only printing in one color (and asking me to select it) instead of switching between the tools. - https://community.octoprint.org/t/error-t-command-was-suppressed-and-not-sent-to-printer/27155


Reverse Bowden

 Really good description of what a 'reverse bowden' setup is for a direct drive printer. - https://forum.prusa3d.com/forum/english-forum-general-discussion-announcements-and-releases/reverse-bowden/ 


To understand what a reverse bowden is, first you need to understand what a regular bowden and direct drive are.

A bowden is a setup where the extruder drive motor is mounted in a fixed place on the frame of the printer. The flexible tube connecting the extruder drive motor to the hot-end and nozzle is referred to as a bowden tube. This tube constrains the length between the drive and the nozzle so when the drive pushes on the filament the force is applied to the hotend. This enforces that when length x is pushed through the drive, the same length x is pushed into the melt zone to have a controlled amount of melted filament pushed out of the nozzle. In this configuration, the only way to pull filament off the spool is by the extruder drive motor pulling on filament because it is presumed that you aren't moving the spool around during a print relative to where the frame of the printer is.

On a direct drive setup the extruder drive motor is mounted to the moving hot-end and nozzle. In these configurations the distance between the extruder drive motor and the hotend is fixed, usually around a couple inches in distance, and almost always in a rigid fixed straight path. (I don't know of any that aren't in a straight path, but I don't know every extruder out there including experimental extruders.) In this configuration, not only does the extruder drive motor pulling on the filament off the spool, but the motion of the extruder assembly can pull filament off the spool if it moves away from where the spool is. This can cause situations where the extruder assembly moves closer to the spool, essentially trying to push the filament back onto the spool. But because the spool won't rewind (unless you have a special rewinder type spool holder) this extra slack can allow a loop of filament to fall off of the spool, potentially causing tangles to happen with the loose filament on your spool holder.

The reverse bowden is one of many ways to mitigate the last issue in the previous paragraph. It is a bowden tube that is connected from the frame of the printer to the input of the extruder drive motor. This constrains the distance between the frame of the printer and the drive motor so the motion of the extruder assembly doesn't change the distance from the extruder assembly and the spool. Often if your direct drive printer doesn't have a reverse bowden then someone out there has designed a setup and you can download the bracket parts that fit on your printer from Thingiverse or similar sites to print them out yourself.

I've played with the idea of installing a reverse bowden on my i3 MK3S, but have yet to have a failure related to not having a reverse bowden, but then again I still use the spool holder that came with the printer so the spool is above the print area. This reduces the amount of potential tangle points along the filament feed path.

BTW, if you do go for the MINI, that is a bowden drive setup so there is no need to add a reverse bowden setup to it.

See my (limited) designs on:
Printables - https://www.printables.com/@Sembazuru
Thingiverse - https://www.thingiverse.com/Sembazuru/designs


Another description of reverse bowden - https://e3d-online.com/blogs/news/battling-bowden-tube-physics 

Search Reddit saved history

 Random useful link here - more and more of my reading lately has been sending things into the blackhole of 'saved' posts on reddit, and they don't even have a search bar! Stumbled on this page that lets you log in, and uses the API from the browser to fetch your history and make it searchable for you!


https://github.com/ahmed-zubair-1998/Saveddit

Wednesday, July 17, 2024

Misc 3d Printing references.

 Working on keeping track of a few interesting posts that I've found around the internet..

I'll be throwing together some links to random bits of information with respect to 3d printing - Links to reddit posts, printables/thingiverse/thangs links for future tracking, all because my personal notes and reddit histories are not very useful for tracking down information!



General 3d printing guides:

https://teachingtechyt.github.io/calibration.html#firstlayer


How to change hot end - 3D printer model https://m.youtube.com/watch?v=OzRAVkXjw3I


3d design guides

https://www.youtube.com/watch?v=Hna4V7-FJ08


Drybox ideas that aren't on printables/thingiverse

https://3d-print-files.com/instruction-diy-filament-dry-box-the-anybox-v2/

https://www.builditmakeit.com/projects/3d-filament-drybox


Original Lack V2 Blogpost - https://blog.prusa3d.com/mmu2s-printer-enclosure_30215/ 



Controlling brim placement with prusaslicer - https://m.youtube.com/watch?v=dhsbMmosbLU&feature=youtu.be - https://www.reddit.com/r/prusa3d/s/9FLv8rOtII


Sequential bridging - https://m.youtube.com/watch?v=KBuWcT8XkhA


Untangle filament - https://www.youtube.com/watch?v=lE9LchCtKL4


How to orient boxes - https://www.youtube.com/watch?v=8NKVNwVaZU0

Overlapping layers between parts - 

Here is a way to make two imperfect pieces that interlock to not show light between them - commonly used for injection molded design, but can make nice 3D prints https://www.youtube.com/watch?v=8dhFhU7Nl_0



How to split an STL into parts in PrusaSlicer - https://3dprinting.stackexchange.com/questions/21777/prusaslicer-how-do-i-preserve-the-location-of-interlocking-parts-in-a-muliti  (found that after looking for an answer to this - https://www.reddit.com/r/prusa3d/comments/1ec3e6a/comment/lexfa7g/ - https://forum.prusa3d.com/forum/original-prusa-i3-mk3s-mk3-how-do-i-print-this-printing-help/overlapping-objects-in-prusa-slicer/ )


Information around multi-material printing with an MMU

https://www.reddit.com/r/prusa3d/comments/1cm8knv/comment/l2za6gg/ - First, make sure you are in Advanced / Expert mode, these are considered Advanced settings.

Print Settings -> Multiple Extruders

In the "Extruders" section, you can set the extruder being used for various parts of the print and tower. "Wipe tower extruder" controls which one is being used for the outer wall of the tower.

-

You also must set the support distance to “0.0 (soluble)”, otherwise it gives a warning about not supporting multiple extruders with the wipe tower.

Of course this is exactly what you want, but if you don’t set the support gap to zero before assigning extruders, it looks like it doesn’t work.



Monday, February 12, 2024

Installing gems in PDK on airgapped/offline system without functional rubygems.org

 I ran into a problem recently installing gems in an offline system... I am not understanding something about how the `pdk bundle` setup creates it's cache directories.


If you try to do a `pdk bundle exec gem install ~/path/to/module.gem`, it will place it's cache files in ~/.gem/ruby, but the PDK expects it's files in ~/.pdk/cache/ruby/


I followed these basic steps to get it 'working' enough...

  1. Copy over .gem file and it's dependencies to the offline system to be able to do a local `gem install`
  2. Install it using `pdk bundle gem install ~/gems/*`
  3. Copy over the installed gems from ~/.gem to ~/.pdk/cache - `cp --no-clobber ~/.gem/ruby ~/.pdk/cache/`
  4. Update your Gemfile (in your PDK base directory) to include the gems you want to local install
  5. `pdk bundle install --local` to install the gems from the gemfile, but source them from the cache that you just manually populated.  
I'd love to know if there is a better way to do this!