Always have to unload filament before loading filament
When I fire up the printer for the day, and it's ready to load filament, it always goes though a filament unload cycle first, even though the filament sensor must be telling the printer that there isn't any filament loaded. Does it work like this for everyone, or just me?
RE: Always have to unload filament before loading filament
When I fire up the printer for the day, and it's ready to load filament, it always goes though a filament unload cycle first, even though the filament sensor must be telling the printer that there isn't any filament loaded. Does it work like this for everyone, or just me?
Hallo and welcome to the Prusaforum!
A common problem or malfunction of the printer is due to misaligned sensors.
I would check the function with a piece of filament. When the filament is loaded the sensor switches to 1 (see LCD menu), when unloading it switches to 0.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Always have to unload filament before loading filament
@karl-herbert
Funny you mention that. I had such a problem after my initial build. I had to tweak things a bit, but now my IR sensor works perfectly. Are you saying that your printer never asks you to unload filament when there is no filament loaded?
RE: Always have to unload filament before loading filament
@fabnavigator
My Mk3S does not ask me to unload the filament if I have done a print job. I have mine set to Single MMU2 configuration so that might be different.
RE: Always have to unload filament before loading filament
When I fire up the printer for the day, and it's ready to load filament, it always goes though a filament unload cycle first, even though the filament sensor must be telling the printer that there isn't any filament loaded. Does it work like this for everyone, or just me?
If you are starting your first print of the day without filament already loaded in a MK3S without MMU, then no, it is not just you.
Some times I unload the filament when I won't be printing for an extended period. When I start to print without filament loaded, the printer recognizes that there is no filament and initiates a filament load sequence where the extruder is raised and moved to the right. It has baffled me as to why the printer prompts me to 'unload' the filament when it has already determined that there is no filament loaded.
This only happens when I start a print without filament pre-loaded. My filament sensor has always worked properly from day 1 and I never get false run-outs.
A thought occurred to me while I was typing this response. Maybe PR is reusing the filament change code in the Firmware to save memory space? When the printer detects a filament out condition, does it just initiate a M600 regardless of the situation? I am not going to lose any sleep over it.
Kenn
Quality is the Journey, not the Destination. My limited prints->
RE: Always have to unload filament before loading filament
@kennd
Thank you Kenn. I like your thought that they needed to conserve memory. As a programmer, I wouldn't think it would take more than a tiny bit of extra code to check the sensor status, but little bits do add up. I always unload my filament when I'm finished printing for the day, so I get his often, but it isn't a big deal.
Recently I asked support for help with something I noticed when I do a belt test. A slight hesitation in the X movement routine and the Y movement routine. One of the support guys and I went thought multiple gyrations about this. I spent hours testing things out. Eventually I got a message from another support person who said "yep, all of our printers to that". It's always nice to hear you aren't the only one seeing something.
Bill