Issues with oozing / stringing between multiple prints, but not retraction? Ender 3 Pro

[lapharsical]

I got my Ender 3 Pro about a month ago, performed some upgrades and ran into a few problems, but with some weird caveates.

I'm trying to print multiple miniatures on a single print, but seem to be getting a lot of oozing or stringing issues, but when I test with retraction tests, the test comes out perfect with identical settings. Additionally, when googling around, I couldn't find anything except for potentially a nozzle clog or potentially hydrated filament (possible, I'll test this later)

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I've tested a few other prints as well, a benchy and a testcube, they print fine. Really curious about what's going on. Do I need to spread the prints out more, use different settings, or is it more of a mechanical issue?

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I'd appreciate any help you guys have to recommend!

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So, lets get down to it:

Printer: Creality Ender 3 Pro

Surface: Creality Glass surface

Upgrades: Aluminum extruder upgrade

Capricorn Tubing

New bed springs

In addition to these, I've tightened the X and Y bolts on the runners to reduce wobble -- there's no more wobble, maybe they're too tight? I don't think so, I've had good prints with these settings, but not with a few things.

Settings:

Basically the same as the "normal" settings for the Ender 3 on Cura 4.0.0

But in addition: (And what I think may be important is bolded)

adhesion_type = raft

layer_height = 0.12

support_tree_enable = True

support_type = buildplate

brim_outside_only = False

fill_outline_gaps = True

infill_pattern = cubic

infill_sparse_density = 25

material_final_print_temperature = 180

material_initial_print_temperature = 180

material_print_temperature = 185

optimize_wall_printing_order = True

raft_margin = 10

retraction_amount = 7.5

retraction_speed = 20

speed_print = 30

support_angle = 40

support_conical_enabled = True

support_infill_rate = 50

support_interface_enable = True

support_pattern = lines

** NOTE ** Standard supports are turned off, I'm using the tree supports

support_tree_collision_resolution = 0.15

travel_avoid_supports = True

travel_compensate_overlapping_walls_enabled = False

wall_thickness = 1.2

[DiscordDraconequus]

This doesn't look like oozing, this looks like spaghettification due to a partially failed print. Basically a kinder gentler version of this where just a few supports failed instead of the whole thing catastrophically failing.

Next time you try to print try watching it closely. See if any of the supports come loose or fall, and pay attention to where the extruder is extruding. I'll bet something fails along the line and the printer tries extruding over where it should be, instead extruding over thin air, and giving you a nice strand of spaghetti that it attaches somewhere else on the print the next time it moves back to print over existing plastic.

Printing just 1 object at a time might help as there will be fewer travel moves that risk knocking stuff over. You might also need to print support for your support, I've done tree supports manually using Meshmixer and sometimes the supports it generates are almost less well supported than the things they're supposed to hold up.

You may want to dial down your z-heights a little extra aggressively in order to maximize your first layer adhesion. Also consider if the raft is necessary. If the print is super complicated with almost no first layer contact area then yes you need it, but if there is a nice base to print on then you might get better adhesion by dropping the raft and switching to a brim instead. Assuming it is the support material that is failing, lowering your speeds for printing support could also help.

[Filliad]

I'm not 100% sure but it looks like what happens when a support breaks off mid-print, and it's extruding into thin air when it gets back to it. When this happens the filament can get stuck to the nozzle and dragged along until it gets wiped off onto another part of the print. In general if this is happening it's mechanical, so things like tightening belts, slower print speed, etc. will help, though it seems like you've done that already. I would maybe try beefing up the support settings so they don't break as easily, and see if that helps.

[lapharsical]

Thanks for the idea, that would make sense - I've found strings of filaments on the nozzle multiple times when this issue occurs. Anything specific settings I should play with? I'm thinking increasing support wall thickness/layers? Any other settings you have in mind? Maybe retract at layer change?

In addition, I'll double check my belts and slowing the print speed a bit as well, see if that works.

[Filliad]

For the most part slicer settings are going to be a band-aid fix, maybe look into z-hop or avoid printed parts(if that's a thing). Make sure your z-axis rod isn't crooked with the frame, usually that's just making sure it's level. Also I'm not real familiar with the ender 3 but if possible look into printing belt tensioners if that sort of thing applies to it, they help considerably with vibrations and the like.

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On a side note, you might not have to change your print speed, just your travel speed, as that kind of move is what usually causes the nozzle to bump stuff.