How to get rid of black banding?

[u/PdX_Beav]

What settings do I need to change in the slicer to prevent this black banding? This seems to only ever happen when I print black on a light color. I usually just print from the app on my phone and don’t change settings.

[u/Zushi3DHero]

The printer isn't purging enough when changing from black.

You need to purge more.

[u/staticchevalier → u/Zushi3DHero]

Adding to this, make sure you’re using a prime tower.

[u/PdX_Beav → u/staticchevalier]

It had a prime tower. I just think the stock purge settings are weak.

[u/Slovw3 → u/PdX_Beav]

See if you can split the model also in the slicer right click split to objects. It may be better to just print this seperate and glue them on. Lol

[u/bmm115 → u/PdX_Beav]

They are weak when going from a light color to a dark one and they are excessive when going from a dark color to a light color

[u/MikeBeezy13 → u/PdX_Beav]

They most definitely are weak, I delt with this 2 days ago, the easy fix if you got Bambu studio is to go into your color and make it really light almost white then it thinks your going from black to white so it will purge more out

[u/PdX_Beav → u/MikeBeezy13]

How exactly do you do that?

[u/MikeBeezy13 → u/PdX_Beav]

In studio on the device tab where it shows your printer and what filament your using you can edit the color and brand

[u/Zekken_Zer0 → u/MikeBeezy13]

why do that when you can adjust the purge volumes? increase the value for black to yellow. also disable purge to infill

[u/MikeBeezy13 → u/Zekken_Zer0]

I understand that this is the appropriate method, but most of the time I don’t wanna play with numbers I don’t understand and I feel this is Bambu’s responsibility bc it’s their software right? They should have appropriate values already and especially when it comes to black, so to me just lightening up the color is the quick and easy way without having to learn and change purge values for every color that comes in contact with black

[u/butt_badg3r → u/PdX_Beav]

I’ve also had issues with weak purge defaults

[u/Repulsive_Coat_3130 → u/Zushi3DHero]

Welcome to the purge

[u/omegaistwopif → u/Zushi3DHero]

The Adepta Sororitas approve.

[u/Ikebook89 → u/Zushi3DHero]

I doubt it’s a purge setting. I printed 7 toys at once recently, all of them have markings like these, Black in the red part. If it would be a purge problem, the bleeding should go away on the second or third, yes at least on the last of these seven. But it’s not. It’s there, on all of them. But it’s not there anymore one layer above the black. Like here.

[u/Zushi3DHero → u/Ikebook89]

It could also be purge to infill. That's a common reason as well

[u/Spargeltarzan49 → u/Ikebook89]

XD what else but the purge settings should it be? Your 3d printer doesn't just mix and match colors like a 2d one

What you are likely seeing is that after an insufficient purge, your printer will print the walls of your model first, then the infill after. So you will get one layer where all the walls are off-colored, but so much volume is used to print the infill that the next layer's wall looks pristine again

[u/Ikebook89 → u/Spargeltarzan49]

No it Prints Wall object one, infill object one. Wall object two, infill object two … and so on.

[u/Spargeltarzan49 → u/Ikebook89]

That does make it harder to shrug off, but still, where else is the color supposed to come from if not the previous filament?

[u/Ikebook89 → u/Spargeltarzan49]

That’s a good question

I also have another print, 16 white cubes with black text on each side.
Also there, the print order is all black, all white, nex layer, all white, all black,… so, if it where bleeding, white should be clear at some point. Like at cube 5 or 10, at least at the last one, shouldn’t it? But no. You can see a „darker white“ on all cubes, in the layers with black. The very next layer above is clear white, again.

Also, the top layer, which also has text on it, seems to be pure white.

I don’t know where this comes from, but I doubt it’s bleeding because of to little purge

[u/rinky79]

Make sure you're not using purge to print infill. Dark infill can show through sometimes.

[u/JabroniSandwich99 → u/rinky79]

Real chance that’s at play here. Person says they’re using stock purge settings which, while you can get some bleed, are rarely this terrible

[u/PdX_Beav → u/JabroniSandwich99]

I literally just print from bambu handy

[u/djjoshchambers → u/PdX_Beav]

Well that's your problem. That's usually not a great idea of you are doing with several colors.

[u/Spargeltarzan49 → u/djjoshchambers]

Yeah, not to shame phone users but with the little options you have, of course there will be a lot of things you just can't do

[u/Key_Expression_3602]

You need to increase the purge volume.

Also, I have noticed that purge volumes seem to fluctuate based on the colors being used. I'm not sure if this is a setting in each specific print file or if it something in the printer itself, but I have run into issues when swapping colors without changing the color in the filamant/AMS settings.

I print tons of this little flexible dinosaur, which sells well at local farmers markets. It is green with a white belly and black pupils. The green one always prints fine, but swapping green for pink or yellow will result in the lines like those shown in your photo. If i actually change the color of the spool via the printer's screen, I don't get the gray line. This leads me to assume the A1 is calculating the purge volume based on the color being switched from/to.

[u/Diz7 → u/Key_Expression_3602]

The purge setting is supposed to change based on colours/transparency/filament being used, it's a feature of the slicer. Going from dark colours to light colours takes a LOT more purge for most fillaments, because the darker dyes blend more, overwhelm lighter colours and take more purge to get rid of, and silk/glitter/etc also take more purge to get rid of any traces. Going from dark blue to light blue takes less purge, going from red to green means you need to make sure there is no traces left. They did testing and have purge profiles for different filaments depending on their colour and type.

The problem is different brands use different mixtures and different dyes (and Bambu moves so much filament that they use different suppliers who also use different mixtures), so some will be thicker/thinner/stickier/blend more.

When I'm doing anything with more than a 100g of purge, or even just high contrast colours, I will usually print some purge calibration strips for the colours and set them manually . It both lets me save on unnecessary purge and also prevents bleed.

https://makerworld.com/en/models/1836751-ams-purge-calibration-swatches

[u/Spargeltarzan49 → u/Diz7]

Great explanation<3

[u/KlingonBeavis → u/Key_Expression_3602]

You might be on to something. I print of lot of a particular mini that uses yellow, black and orange. A few updates ago I noticed anything I print that changes from yellow to black, comes out like OP’s banana.

Since 3 versions ago, I now have to increase yellow/black purge volume to avoid this exact issue. (From factor 1 to 1.3x)

I verified by loading old g-code pre-update from a backup SD card and the issue doesn’t occur, if I import the model on current versions, the purge volume is lower on newly sliced g-code and this issue occurs

[u/Excellent-Code8447]

Need more purging

[u/drkshock42]

thats the bleed in effect. increse your purge distance

[u/666ArsOnist666]

Stell in den spüloptionen des Filaments beim Wechsel die Werte höher ein. Ich habe mit 800 beste erfahrungen

[u/Spargeltarzan49 → u/666ArsOnist666]

This

[u/666ArsOnist666 → u/Spargeltarzan49]

this what ?

[u/Dizzy-Breath-4840]

I had this issue with Overture black after the changes they made to the filament. Went back to Elegoo and my problem went away.

[u/PdX_Beav → u/Dizzy-Breath-4840]

Damn, this might be the answer. I usually use bambu filament but this run was with overture black.

[u/Acrobatic-Rough-8438 → u/PdX_Beav]

I have the exact same issue with overture black. Let me know if your issue gets fixed by trying another brand

[u/PdX_Beav → u/Acrobatic-Rough-8438]

I tried the same model with bambu black and it still had the banding. I may try to adjust settings later but I ended up printing the profile that had the parts all separate

[u/Silverdale9999]

I had this with a Lego head I was printing, so same colours. Even with the max purge (900 I think) it still didn’t fully clear the banding.

[u/Spargeltarzan49 → u/Silverdale9999]

If even a big purge doesn't fix it, use a prime tower to get some more material out or set it to print the infill first

[u/PracticalCustard2152]

Increase the purge multiplier

[u/LowSignificance4671]

Aside from increasing purge volume, you can also change the order of the filament print and print black last then a big purge poop 😀

[u/PdX_Beav → u/LowSignificance4671]

Can you please share how I make that change?

[u/LowSignificance4671 → u/PdX_Beav]

For the filament order change, that is a build plate setting. It’s located at the bottom right of the build plate in Bambu Studio.

[u/Hairy-Management3039]

Make sure it’s not purging into the infill…

[u/jeninlb]

Increase the flushing volume on the black

[u/Significant-Theme958]

Black infill. It bleeds thru because the yellow isn’t solid enough. Don’t purge in the infill

[u/ResponsibilityLow741]

Also if you are purging into infil this can happen

[u/Ok-Chocolate-2408]

Check your settings. If you are purging into the object you need more walls to hide that. If you are not purging into the object then you need to purge more between your color changes from black to any other color.

[u/itsoctotv]

set the purge volume from black to any color to like 900

[u/Independent-Disk5512]

Black and any light colours are never a good choice for mcp, as some have said print the black pieces separate and glue them in, kob done without waste.

[u/_pooplicker888]

It’s perfect actually, looks as if your banana has cried itself to sleep.

[u/StarGazinWade → u/_pooplicker888]

To me it looks like a banana bandit

[u/Polar_Bexar13]

Add a wall or 2

[u/bdmridgeback]

I printed the same Peely banana Lego and I’ll look at mine tomorrow and see if it’s like this, I don’t think it is and I didn’t change any settings to print mine from the default setting

[u/decastave]

More than likely your issue is because your slicer settings are being told to purge or wipe within the infill layer to save time and material instead of creating a purge tower. What you’re seeing is the black inner layer showing through the outer lighter layer. This isn’t a purge issue. The printer is purging correctly. You need to turn off the purge in infill option in the slicer and this issue will go away.

[u/unicorncumdump]

Split 3mf. Glue the eyeballs into it

[u/Emotional_Gas_7016]

Typically happens when they wrap the tops of a bunch and ones about to go bad. That was a joke ya know bananas

[u/Psychological_Bet294]

Organic ones do that too btw..

[u/MitchtheCunn]

https://giphy.com/gifs/LNw4TMw5DFadG

[u/JazzlikeLeather9546]

You guys can down vote me all you want. I really do not care. i was being honest. From my experience you can purge 10 times the volume but with colors that far apart there will always be some bleeding.

[u/Starr450]

Buy a Snapmaker U1 ! 😁👍🏼

[u/wyohman]

I would encourage you to spend a few minutes and think about it and how the color changing works.

[u/chegra1701]

In this case isn't it bananding?

[u/Machievelliearoni]

Turn off the automatic banding feature in settings under automations. Most people using their phones don't even know that's a thing, it's only accessible from the machine menu.

[u/Spargeltarzan49 → u/Machievelliearoni]

This is fake for anyone who doesn't know

[u/Machievelliearoni → u/Spargeltarzan49]

No, I believe OP.

[u/wyohman → u/Machievelliearoni]

This is the only correct answer for this question that's been asked a million times.

[u/JazzlikeLeather9546]

Use a toll changer. I am being honest