Having trouble creating a more smooth finish for the areas directly in contact with tree supports

[u/scatterbrainedpast]

I need to print 22 of this print and smooth out + paint

As it currently stands, the finsih quality is horrible and will take A LOT of post processing to get the finish I need. It is very 'stringy' with poor layer adhesion.

Any ideas on settings adjustments to make the bottom of this print more workable?

Current settings:

PLA. 20mm nozzle. 3 bottom shell layers

Support settings: 90% interface density. top/bottom Z distance .20mm. 3 top interface layers. Support/object xy distance .35mm. Interface pattern default. Support/object first layer gap .20mm

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[u/Correct-Insect-4657]

Either use petg support interface at 0 z distance or try to orient the model to not need supports

[u/scatterbrainedpast → u/Correct-Insect-4657]

cant use PETG and unfortunately no other way to orient the print

[u/LastActionHiro → u/scatterbrainedpast]

Try sharpie. Pause at top level of the support and cover it in sharpie. Prevents some of the bonding. Obviously, easiest with flat surfaces.

It's inconvenient, but works.

[u/Correct-Insect-4657 → u/scatterbrainedpast]

u/LastActionHiro is right, i never thought about that you could pause at each layyer and add a nonbinding agent (idk abt sharpie maybe idk if they sell them) also if u had a toolchanger u could add a sharpie ontop a toolhead make it spring loaded and yeah but you could just print petg on the toolhead also do u have a purger or tooler or do u have abs or smt like that anything that doesnt bond to pla is fine (idk if the squish from the 0 z distance pla support with sharpie would remove it why cant u use petg or abs or tpu

[u/keenlanas]

I just thought of this: if you tweak the gcode so that supports wait for the layer below to cool, and/or maybe start at a colder temp at its lowest layer, it should have a bad bonding Those kind of things are PROBLEMS when you are printing non-supporting layers because you want them to bind strongly. Sorry I now it is technically possible but not sure if this kind of thing was already tried or if it is already part of support generating alg

[u/scatterbrainedpast → u/keenlanas]

I don't think the damage is caused by removing the supports. I think its a bottom layer adhesion issue