Filament build up while bed leveling
Hi,
I received my assembled Prusa i3 MK3 a couple of weeks ago and have been playing with it quite a lot.
There are still a couple of things that puzzle me:
- How to change the G-Code in Slic3r so that the filament doesn't build up around the nozzle when bed leveling and heating up
- How to avoid stringing with Slic3r (stringing does not happen when I use the standard settings of Cura)
Thank you in advance!
The first part is definitely the most problematic: I have to remove plastic build-up from underneath with twizzers while the head is moving literally every time before printing (the intro line does not get rid of the issue)
Re: Filament build up while bed leveling
There are several different threads with slight variations in gcode to address the oozing during leveling. You can see mine in the post I linked below.
If you haven't already, calibration your extrusion multiplier, and your linear advance factor. While not directly related to stringing, over or under extruding makes fixing other stuff hard. As far as Slic3R settings go, I ended up with a retraction length of 0.4mm, Z lift of 0.5mm, retraction speed of 45mm/s. I have also found that temperature can play quite a role in stringing and going up or down five degrees may solve the problem too.
Find a small print that exhibits stringing for you and then print it, but only change a single setting for each print. Its a bit time consuming, but if you are changing multiple things every time, you don't know what is actually making it better, or worse.
Re: Filament build up while bed leveling
[...]- How to change the G-Code in Slic3r so that the filament doesn't build up around the nozzle when bed leveling and heating up
I've had good luck with the following basic flow:
This procedure has worked for me in both eliminating the dots and strings scattered across the bed during leveling, and kept PINDA temps consistent for leveling, which seems to have helped with 1st layer results. There are several threads on these topics here on the forums. I've just assembled a couple of techniques into on set of gcode. You can see my g-code and comments here if you're interested.
One cautionary note: Be careful before you start slinging the extruder around in startup g-code. You need to make sure the extruder knows where it is by homing lest you send it careening into your print bed.
- How to avoid stringing with Slic3r (stringing does not happen when I use the standard settings of Cura)
Simplify 3D has a really nice print troubleshooting guide that summarizes the basics nicely. Stringing is usually a question of temp, retraction, and movement speeds. I have run into a weird problem where the filament profile I create in Slic3r has stringing issues even when using the same settings as the defaults. When in doubt, try changing filament selections to the defaults (e.g. Generic PLA) and comparing. It also helps to find a 10 minute print that will identify stringing issues.