What is causing the walls of my prints to separate?

  • I have been having an issue with certain portions of the walls of certain prints becoming separated from the rest of the model. It happens with smooth vertical edges.

    Specifically, this model, ID Badge Holder, on the edges where the lanyard would be attached. And on several places on this model, Cat Necklace.

    Here is the resulting issue:

    Detached print wall

    I am quite new to 3D printing, so I'm sure this is an easy fix, I just don't know about it yet.

    I am printing with a Monoprice Select Mini V2, using Hatchbox PLA, and the default slicing settings inside Cura. I don't have problems with any of the D&D figures I've printed, or some of the other thicker square pieces I've printed. I know I've got kind of a bargain printer; if it's just a quality issue I have to learn to live with, no problem. But if an expert knows of some slicer settings to tweak for these kinds of prints with flat vertical walls, I'd love to give it a try.

    Can you post the default settings in use for extrusion speed, wall thicknesses, layer height, at the least. "Default" varies by defined printer and by Cura version.

    Please include the photos. Also please include photos of the model as links do not last the test of time.

    @StarWind0, I've attached an image of the issue I'm experiencing.

    @CatsAndCode Looks like your lines of the faces and not touching; under-extrusion? Or are you printing with no top and bottom faces and high infill? Have you checked filament diameter, filament settings in slicer and checked the length your extruder prints (when you ask for 50 mm, does actually push 50 mm forward)?

    @0scar The more I'm reading everyone's responses, the more I think it IS an underextrusion issue. I am not sure how to create the "top and bottom faces" you mentioned in Cura. I'm printing at 10% infill. Filament diameter is set correctly in Cura, but I haven't done any calibration/verification on my printer. It was allegedly set up at the monoprice factory, so that's been working for me thus far.

    @CatsAndCode I updated my answer. If you select 0 mm layer thickness and 95% infill you get the exact same faces as your print. I print stuff for a colleague who uses the products in a vacuum chamber as molds, without skins you cannot trap air :)

    does it work better if you slow down the print speed?

  • 0scar

    0scar Correct answer

    4 years ago

    I have faced the same issue if it concerns just gaps between the walls (to the point you could put a nail in between the outer and inner perimeters, so clearly the perimeters were not bonding), for me this was fixed with proper tension of the belts of my Prusa i3 clone, and for my other (CoreXY) printer reducing the friction of the X-Y system. Both help position the head better for proper wall adhesion.

    Now that you have posted a picture of your product I do not think the above is applicable to you. Your print looks as if it has an under-extrusion problem as the lines on the faces are clearly not touching, you see the diagonals of the layers beneath. This under-extrusion also may contribute to the vertical wall bonding problems you mention. To fight under-extrusion you need to check a few things:

    1. Be sure the slicer has the actual filament diameter as mentioned on the box, or measured at various points (if it varies, take the mean value).

    2. Check your extruder setup to see whether you have play or friction preventing filament to extrude freely.

    3. Also check whether your extruder gear is not loose, re-tighten the grub screw.

    4. Final step is calibration. You want to be certain that when you demand 100 mm of filament to extrude, you actually extrude 100 mm. Put a mark on the filament and extrude 100 mm using a tool like Pronterface or Repetier-host. If this is off you should readjust the steps per mm in the firmware (if you are able to do so), or increase the extrusion multiplier or flow in your slicer.

    Please look here or here for more information.

    "You want to be certain that when you demand 100 mm of filament to extrude, you actually extrude 100 mm" This. On my MP Mini I've noticed that the default extruder steps per mm is wrong. I think the default is something like 97, and every time I calibrate it, it's more like 105. This was leading to constant underextrusion for me until I did an extruder calibration.

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Content dated before 7/24/2021 11:53 AM