Notifications
Clear all

Curved walls  

  RSS
Reini
(@reini)
Active Member
Curved walls

I designed and printet drawer inserts but when I print larger versions the walls are not straight but curved on the longer side.

I tried different settings in PrusaSlicer 2.5 with leads to faster or slower prints, added more cooling, print 6 at a time, etc. but nothing helps.

The longer walls are always curved (print is on the right side):

 
Can this only be fixed with thicker walls or can I do anything else to get straight walls?

Attached are 3 3mf files one with my "0.3 mm speed" settings for a print of less than 2 hours per box (6 boxes overall) and 2 versions with more or less default prusaslicer "0.2 mm quality" settings.

Thanks in advance.

Reini

Posted : 12/11/2022 6:00 pm
Neophyl
(@neophyl)
Illustrious Member
RE: Curved walls

No files attached. You did zip them up first didn’t you ?  The forum only allows a limited number of file types, 3mf is not one of them which is why you have to zip them. 

Posted : 12/11/2022 7:00 pm
Reini
(@reini)
Active Member
Topic starter answered:
RE: Curved walls

Sorry but I tried it with Firefox and Chrome on Windows with "Attach file: ...".
The file is shown but not attached.
...and yes it is a .zip file.
Now I try drag'n'drop, maybe this works...
Drawer-Insert_EuroPlus-63-2x1-1.3

Posted : 12/11/2022 7:28 pm
Reini
(@reini)
Active Member
Topic starter answered:
RE: Curved walls

Seems the file is added.

Posted : 12/11/2022 7:29 pm
Reini
(@reini)
Active Member
Topic starter answered:
RE: Curved walls

Model can be found here: https://www.printables.com/de/model/315929-drawer-insert-freecad-parameterized

Posted : 12/11/2022 7:52 pm
Diem
 Diem
(@diem)
Illustrious Member

The walls are only three extrusions thick so yes, thicker should help.

Looking at the source page, the photo shows slightly curved walls too...

  You might have less stress to redistribute if you changed to chamfered corners.

How bad is the issue if you print just a single part in the centre of the bed?   Iow: is there an issue with retained heat?  In which case lowering the bed temperature a little after the first few layers might be worth trying.

Cheerio,

 

Posted : 13/11/2022 12:43 am
Neophyl
(@neophyl)
Illustrious Member
RE: Curved walls

Why have you turned your fan up to 90-100% with petg ?  Its likely that is causing your walls to warp through excessive plastic contraction due to cooling.  Put your filament settings back to near stock, just keep the lower 'slow down if layer time is below' value but change the min print speed there to match your small perimeters.  That way it wont slow down too much which can cause its own issues.

Posted : 13/11/2022 12:49 am
Diem
 Diem
(@diem)
Illustrious Member

Well spotted @neophyl, I missed that.  What do you think about 'opening' stresses from the rounded corners?  I should really do some tests but I suspect the shape inherently biases any distortion...?

Cheerio,

Posted : 13/11/2022 2:16 am
Reini
(@reini)
Active Member
Topic starter answered:
RE: Curved walls

@neophyl: I think I did all you mention and print again but it is the same problem. I hope I did not miss something to change.

Drawer-Insert_EuroPlus-63-2x1-1.3 (2) (zipped 3mf file)

@diem: The source page is mine and this are all my prints trying to get the walls straight. I still can use this boxes but it would be fine if they did not have curved walls.
I will try to replace fillets with chamfers. Maybe this helps.

For stability the wall thickness is enough but maybe it is not printable ...

Any other ideas/settings I can do/change in the slicer to fix this?

Thanks in advance.

Reini

Posted : 13/11/2022 12:16 pm
towlerg
(@towlerg)
Noble Member
RE: Curved walls

What a pity this forum lacks the ability to create sticky posts. Number 1 should be chamfers trump fillets, never touch the build surface with your finger and use boiling water and washingup liquid to clean the build surface (perhaps not in that order).

Posted : 13/11/2022 1:32 pm
RandyM9
(@randym9)
Honorable Member
RE: Curved walls

Let’s not forget ’Life Adjust Z - my way’

Posted by: @towlerg

What a pity this forum lacks the ability to create sticky posts. Number 1 should be chamfers trump fillets, never touch the build surface with your finger and use boiling water and washingup liquid to clean the build surface (perhaps not in that order).

 

Posted : 13/11/2022 3:48 pm
Reini
(@reini)
Active Member
Topic starter answered:
RE: Curved walls

@towlerg: Can you please explain me why chamfer is better than fillet? Have you some resources where I can read more about this and maybe other things that I should consider when designing models for 3D printing.

 

I have no adhesion problem. The print sticks pretty well at the bed and can be removed very easy when the bed is cold.

The curved walls are at the side not at the bottom.

So any other ideas/settings I can do/change/try in the slicer to fix this?

Thanks in advance.

Posted : 16/11/2022 7:31 am
Neophyl
(@neophyl)
Illustrious Member
RE: Curved walls

A chamfer on the 'bottom' edge of a design (placed on the bed) can be printed using 3d printing techniques as generally your printer can handle the amount of overhang.

A fillet when its starts is almost all overhang, as such it needs support, unfortunately its too close to the bed to fit support under it.  Its not until the curve gets closer to vertical that it becomes printable.  That's why a chamfer or a hybrid chamfer/fillet is preferred in designs that will be 3d printed.

I don't think that has any bearing on your wavy wall problem though.  Its not the bottom that is having an issue but the vertical walls.

As an experiment try printing one in a different material, such as pla (sliced with the correct pla filament profile of course) and see if you have the same issue.  

Posted : 16/11/2022 8:06 am
Reini
(@reini)
Active Member
Topic starter answered:
RE: Curved walls

@neophyl Thanks for the explanation.

At the bottom it is a chamfer, the on the side walls and inside the box there are fillest. So there should not be a problem with overhang.

I reduced the heat bed temperature that reduced the wavy wall problem. I was able to print with a wall thickness of 1.2 mm and it was "ok". I used 65°C/70°C for the 2x1 box. For a 2x2 Box this was too low as there was a little warping so I increase it to 70°C/75°C. At the moment I print a 2x2 box again with the increased temperatures. Lets see if this works ...

Filament is Jayo PETG (which seems to be the same as SUNLU when comparing the spools) and this seems to needs a  much lower heat bed temperature as Prusament PETG, which was my starting point for the settings.

Posted : 16/11/2022 8:06 pm
Share: