Does anyone know why my printer wants to purge when I am printing in a single colour? It is wasting my time and filament and due to the poor design of the AMS unit I get pullback problems every time. To say this is annoying is a understatement. I am trying to print out the Hydra conversion to sort out the poor design however baby sitting the printer for days to get the prints completed is not something I am keen on doing. Bambu Lab should be shipping a fix free of charge!
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What is your time lapse setting on?
Hydra won’t fix this problem, just allow you to use differ sized rolls.
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I know the hydra wont fix the purging however it will hopefully fix all the other problems I am having with it. The bizarre thing is that when I use slot three it doesn’t flush which has me even more confused.
I am not sure what you mean regarding time lapse? Is it better to have it off?
Are you talking about the purge at the start or is it purging randomly mid print too? The purge at the start is normal and not a big deal.
There is a specific time lapse setting, I think it’s called “smooth,” that parks the tool head over the chute after every layer to do a photo without the tool head in the way to make a better looking time lapse. Makes it seem like it’s purging when it really isn’t and adds a lot of time to the print. It might purge a little and/or wipe the nozzle a bit to make sure you don’t get blobs when starts the next layer.
What filaments?
I am using a 3D Marvel PLA
Maybe you can post a few pictures from studio. You model and your sliced part?
He could check this at his poop-box. Look at the size and amount of poops your printer throws out.
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That was what I thought might be happening however it doesn’t explain why it doesn’t do it when I load the filament into slot 3 yet does in slot 1 & 2.
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Yes, this sounds a bit strange. Thats why i asked for some pictures from BambuLab studio and the file you printed and how it looks after slicing etc.
I am printing at the moment the left hand side of the hydra upgrade, it has a hour and twenty minutes to go. It is 9:50pm Friday night here so I will be heading to bed after it has finished I will post some pics in the morning.
I have just uploaded the time lapse of last nights print.
You can modify the start gcode, but you are going to have to do a lot of baby sitting loading/unloading and purging manually if you do change things. You can however reduce the purge a little and still have the full automation that still works perfectly. I’m currently using 40mmx2 purge vs stock 50mmx2 (purge is done twice). I might test reducing it more.
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Just edit the printer start g-code:
The command E50 extrudes 50 mm of filament.
So set to 10
That’s it.
Hello,
Thus I was not the only one who experienced the roll in roll out when there was no reason (one color too).
I couldn’t reproduce the issue but I noticed something during the printing.
The spool filament came to the end and sometime jumped into the AMS slot. Maybe at this moment wrong informations were sent to the printer which involved the roll out? idk.
The only way I’m aware of is editing the start gcode as mentioned above. You can do this for each of the stock profiles and save them with original name + “minimal purge” for any prints with no filament change needed at start.
Keep in mind that the printer is rewinding the filament into the AMS after ending a print successfully. For that it has to cut the filament in the extruder and the part between the cut and the nozzle is still inside the hotend. On the next print the printer cannot do any retraction until this piece of filament has been fully extruded through the nozzle. If you reduce the purge volume too much this might lead to additional oozing during initialization and first seconds of the new print probably compromising quality of your print.
I can understand Bambu didn’t want to risk these potential problems to just save a tiny amount of filament.
Bambu could change the behavior of the AMS to not rewind filament after a print and do it only when the printer switches filament slots or the printer has lost the information of the last slot used. This has the inconvenience that you cannot change the spool in the last used slot unless you power-on the printer and start the rewinding manually. Again I don’t think Bambu would sacrifice this convenience for a tiny bit of filament savings.
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First I thought about rewinding filament back as a nuisance, however after thinking a bit changed my opinion. It may be OK to not rewind PLA or ABS to lesser extent, however for PVA, PETG and Nylon it’s essential. Otherwise you will get crappy printing in the beginning as they quickly absorb moisture, or even clogged AMS in case of PVA.
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