Strange texture change at inner diameter reduction of part - never seen this before.
 
Notifications
Clear all

Strange texture change at inner diameter reduction of part - never seen this before.  

  RSS
CamStLouis
(@camstlouis)
Eminent Member
Strange texture change at inner diameter reduction of part - never seen this before.

I am printing the barrel joint to a mid 1800s flute, basically just a cylinder with a tenon socket. All the other prints for this flute have gone great, but something weird happened once the printer arrived at the thinner section:

Odd surface finish

The inside was also strangely zitted in a way I haven't seen before:

Additional macro shots are here: https://imgur.com/a/eX4Qlss

I'm using Polymaker ASA Black, which prints like a dream and vapor polishes just like ABS. None of the other parts for this flute have come out like that, so I'm just curious what happened. Unfortunately I didn't catch it as it was happening. The part should be fine, I just would like to know what happened!

Thanks as always for your insight!

 

Posted : 02/08/2022 2:05 am
fuchsr
(@fuchsr)
Famed Member
RE: Strange texture change at inner diameter reduction of part - never seen this before.

I'd step through the layers in preview and check on the infill in that region and play with extrusion width to smooth it out.

If you upload your project as a 3mf file, you're likely to get advice that's more than just a guess. In Prusaslicer, go to File/Save project as, to create the 3mf file. Zip compress it (right click Compress on Mac and Win11, right click Send to/Compress on Win10) to turn it into a .zip file, which you can attach to a post on this forum. The forum software does not accept .3mf files, it has to be a .zip file.

The 3mf file contains not only the STL but also all your settings.

Posted : 02/08/2022 2:43 am
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE:

FlutePrint - Didn't attach first time!

I couldn't see anything in the layer preview or settings that would indicate something different, and the other parts in the print series all printed just fine. This is part of a larger pattern of artifacts I get every once in a while when printing changing widths of cylindrical objects - sometimes the ID or OD will be out, with a pronounced "step" not reflected in the layer preview.

Posted : 02/08/2022 3:03 am
mark
 mark
(@mark-3)
Reputable Member
RE: Strange texture change at inner diameter reduction of part - never seen this before.

Can you print it upside down? ASA does not print well when there are overhangs. Ideally, the part should always be larger at the bottom. You can also split it into parts and glue them together such that each part only gets smaller as it goes up.

Regards,

Mark

Posted : 06/08/2022 9:38 pm
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE: Strange texture change at inner diameter reduction of part - never seen this before.

I think you’re looking at a different file than I am. The part has no overhangs, just an increase in inner diameter for the last 1/3. 

Posted : 11/08/2022 10:40 pm
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE: Strange texture change at inner diameter reduction of part - never seen this before.

https://imgur.com/a/D9kfKbK

Tried again with PLA and a different layer height (0.15). Same result; this weird texture and slightly oversized OD. Any idea what’s going on?

Posted : 15/08/2022 6:19 pm
mark
 mark
(@mark-3)
Reputable Member
RE:

 

Posted by: @camstlouis

https://imgur.com/a/D9kfKbK

Tried again with PLA and a different layer height (0.15). Same result; this weird texture and slightly oversized OD. Any idea what’s going on?

You should include images on the forum. External images often disappear and future users can't find them.

How are you printing it? If the thinner wall section is toward the bottom, then there is an overhang. The top of the part should be the thinner part. It's possible that it's too thin. It is extruded in a particular width. Maybe it can't fit enough passes. Slice it, then drag the slider in the slicer to look at how it is laying down filament. Sometimes that will help you visualize what it's trying to do. It can't make some geometries due to minimum extrusion widths and heights.

Maybe try the new slicer Arachne extrusion.

Regards,

Mark

This post was modified 1 month ago by mark
Posted : 15/08/2022 6:57 pm
Ringarn67
(@ringarn67)
Reputable Member
Rectilinear infill

@camstlouis

Try printing it with Rectilinear infill instead of Gyroid.

I printed your Headjoint upper, cut it  down for speed, with rectilinear infill and it looked great.

I will clean up, lots of small test in it right now, and upload my file tomorrow if you are interested, must go to bed now 😴 

Prusa i3 MK3S+ FW 3.11.0 (kit dec -20), PrusaSlicer 2.5.0+win64, Fusion 360, Windows 10

Posted : 15/08/2022 8:04 pm
Ringarn67
(@ringarn67)
Reputable Member

I print on i3mk3s, but I don't think the problem is printer related 🤔 

Prusa i3 MK3S+ FW 3.11.0 (kit dec -20), PrusaSlicer 2.5.0+win64, Fusion 360, Windows 10

Posted : 15/08/2022 8:12 pm
fuchsr
(@fuchsr)
Famed Member
RE:

I printed a copy of the model on a Mini, using my standard ASA 0.3mm layer height profile (I don't see a reason to go more detailed than 0.3 for a model like this). Printed just fine without any tweaking whatsoever. I didn't dry the ASA so there are some bumps on the outside but I don't see any of that pattern you're seeing. I thought it might be infill or gap fill related but I used gyroid like you did, so infill is not the culprit. Not sure where that leaves us. I'm attaching my profile so you can do a print with it. If that comes out fine, it's something in your settings and you can do a comparison of your profile and mine. If it still looks bad, this points to something hardware related, me thinks.

This post was modified 1 month ago by fuchsr
Posted : 15/08/2022 10:06 pm
Ringarn67 liked
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE: Strange texture change at inner diameter reduction of part - never seen this before.

Hi all, I really appreciate your help with this issue! I want to clarify a couple things, though, as it seems like there is some confusion over which part and what the issue is.

The only part affected by this issue is the barrel joint, a portion of the headjoint assembly accepting the tuning slide and connecting to the main body of the flute (green).

 

The headjoint upper is really just a sleeve to make the embouchure insert (I am trying different embouchure cuts) look more like a normal flute headjoint, and didn't experience the problem that the barrel joint did, although they are similar in height. If the z-axis had a hardware problem, I would expect it to show up on the same layer on the other parts, but the barrel joint was the only one affected. I print a lot of high aspect ratio components and only a few of them are affected, and not at a layer height, only rarely at a change of diameter (like a tenon joint or portion of a taper).

I think this is a software issue where PrusaSlicer is not quite correct about how many extrusion widths can fit in one place, and maybe there's a slight nozzle crash on the second-to-outer extrusion happening, deflecting the last extrusion outwards.

Everything looks normal just before the transition to the tenon:

And then, what I thought was a single extrusion is actually two overlapping lines. Hard to see!

I was positive I had "detect thin walls" on, but it turns out I disabled it to print an embouchure insert, since ironically, it tends to break truly thin walls into little dot artifacts rather than consolidating overlapping lines.

Turning it on replaces the overlapping lines with a single extrusion, which I think will solve the problem. I have a print running now but will report back with results.

Posted : 15/08/2022 10:52 pm
fuchsr
(@fuchsr)
Famed Member
RE: Strange texture change at inner diameter reduction of part - never seen this before.

Uh, then why didn't you post the part that was actually having the problem? In the 3mf file you posted, there were three parts, and the "headjoint upper" was the only one even remotely resembling the photos.

I mean, I and others here are happy to help people but I'm sure none of us is too keen to be sent on a wild goose chase. 

Posted : 15/08/2022 11:06 pm
Ringarn67 liked
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE:

I specified that it was only the barrel joint in the first post, and the part was named accordingly in the file. I was asked to share the print file that produced the part, and I did so without alteration in case something about the sequential output was causing the issue. I could have been clearer, but I didn't realize people were intending to print the part - I thought we were examining settings and Gcode.

This post was modified 1 month ago by CamStLouis
Posted : 15/08/2022 11:51 pm
Ringarn67
(@ringarn67)
Reputable Member
Posted by: @camstlouis

I specified that it was only the barrel joint in the first post, and the part was named accordingly in the file. I was asked to share the print file that produced the part, and I did so without alteration in case something about the sequential output was causing the issue. I could have been clearer, but I didn't realize people were intending to print the part - I thought we were examining settings and Gcode.

There is no "barrel joint" in the file!

 

Prusa i3 MK3S+ FW 3.11.0 (kit dec -20), PrusaSlicer 2.5.0+win64, Fusion 360, Windows 10

Posted : 16/08/2022 3:34 am
sandysasmita
(@sandysasmita)
Trusted Member
RE: Strange texture change at inner diameter reduction of part - never seen this before.

 

Posted by: @camstlouis

https://imgur.com/a/D9kfKbK

Tried again with PLA and a different layer height (0.15). Same result; this weird texture and slightly oversized OD. Any idea what’s going on?

If i'm not wrong, this is maybe a side effect of cooling settings (smaller part have slower print speed) and the print surface will have a different results. Can you confirm in the gcode file that the upper side has slower speed? If that is true, you can try to make the speed equal by changing the cooling settings at the filament settings tab in prusaslicer (slow down if layer print time is below : xx seconds).

well i don't know if this will work or not, but worth to try.

Posted : 16/08/2022 7:51 am
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE: Strange texture change at inner diameter reduction of part - never seen this before.

Well, shit, I must have overwritten the file with the next batch of parts and forgot. Totally on me! I'm opening my own instrument shop soon and lack of sleep is catching up. Thanks in any case for trying to print the part - more than I expected!

Thankfully, enabling "detect thin walls" solved the problem - it looks like it was a case of two overlapping extrusions there. There's a faint trace of a line where the diameter changes, but these were good to +/- 0.05mm which is adequate for flutemaking.

Posted : 17/08/2022 2:15 am
CamStLouis
(@camstlouis)
Eminent Member
Topic starter answered:
RE: Strange texture change at inner diameter reduction of part - never seen this before.

Here's what the instrument sounds like (earlier version in PLA).

Posted : 17/08/2022 2:26 am
Ringarn67 liked
Share: