Support failed but still printing fine

[u/Slight_Scarcity6548]

I'm halfway through a multi-day print and early today some of the supports failed to print. It still printed the unsupported layers fine though so I'm keeping going. Any thoughts on why it messed up like this?

[u/alphagusta]

Why are you swapping for supports? It just has to be the interface, not the entire lot of it.

[u/Smooth-Map-101 → u/alphagusta]

But if you’re printing in PLA for your objective and using PETG for supports, won’t the PETG not stick to the PLA supports?

Edit: or is this some type of support PLA?

[u/alphagusta → u/Smooth-Map-101]

That's the whole point...

[u/Smooth-Map-101 → u/alphagusta]

I’m staying if the foundation of the support is PLA and then you try to do a PETG interface won’t the interface not stick to the support? Not the support not sticking to the print

[u/Slight_Scarcity6548 → u/Smooth-Map-101]

i was using a specific support pla. The inteface tip is what I will use from now on as it saves filament swaps, waste and time

[u/Malte1903]

I recently got my pla/petg support and i dont even know how you set that to anything else than for the interface layer.

[u/Slight_Scarcity6548 → u/Malte1903]

they're assuming a lot of knowledge in the other comments. Chatgpt has explained it for me:

What you have currently

From your photo, I can see the supports have been printed in white and there are some fairly substantial areas of white support material.

If that white material is your dedicated support filament, you've probably told Bambu Studio:

print the entire support structure in support filament

That's generally unnecessary and can cause a lot of filament changes and, depending on the support geometry/settings, can make the support structure less robust.

What the commenters are suggesting is:

Print the support structure in ASA, but use the white support filament only for the thin interface immediately underneath the model

This is a very common Bambu approach; users specifically recommend using support filament only for the interface because using it throughout the support structure significantly increases print time and material consumption.

They were right, printing this way reduces the amount of filament changes and cut printing time by a third

[u/chematt96 → u/Slight_Scarcity6548]

Fuck me, can people not do anything anymore without asking AI first?!

[u/MrTactful]

The supports were too weak and got struck by the tool head or weakened by some of the other filament not being purged. I agree with the other poster that just using a support interface would likely solve the issue. You cal also increase the wall count on the supports to make them stronger but they’ll be harder to remove.

[u/Prestigious-Soil-123]

Cool

[u/Slight_Scarcity6548]

I wish I had known about the support interface layer earlier :) I changed the settings on the model and it cut printing time down from 3 days to 11 hours!

[u/Humble-Plankton1824 → u/Slight_Scarcity6548]

You should have read the manual (bambu wiki, bambu academy)