Holes/gaps where they seam is

[Xhoax 4]

Where they seam is we have little holes/ gaps.

 

The print is perfect, just the little gaps are a problem.

 

How can this he fixed?

 

Materiaal: viber PLA (colorfabb)

Nozzle: 0.4

[Slashee_the_Cow 409]

It looks like a bit of overextrusion or (wild theory) a retraction problem? Almost looks like a bit is pulled out at the seams.

I'm going to leave an expert analysis to @gr5.

[gr5 2,224]

I recommend you do a small test print - just a cube with minimal infill (maybe 10%).  Anyway usually slowing it down by about 20% will fix this.

 

Personally I'd set all the printing speeds to be the same speed as well as that can fix some surface issues but I think just slowing down your print speed will make a big difference.

 

Please do some test prints before reprinting this model.

[Xhoax 4]

On 7/8/2024 at 4:35 PM, gr5 said:

I recommend you do a small test print - just a cube with minimal infill (maybe 10%).  Anyway usually slowing it down by about 20% will fix this.

 

Personally I'd set all the printing speeds to be the same speed as well as that can fix some surface issues but I think just slowing down your print speed will make a big difference.

 

Please do some test prints before reprinting this model.

I did the test, not the cube like you suggested, but the 'benchy' boat.

(Because we print organic forms)

 

See photo's for result.

The walls are ok, but not so great.

We got some overextrusion.

We set tree supports.

 

Speeds:

Print speed: 50mm/s

Infill speed: 50mm/s

Wall speed: ( in and out the same):30

Initial layer speed: 15

 

[gr5 2,224]

Benchy is designed to have no support.  So I'd turn that off.  Did you cancel it before the chimney or did it fail?

 

So I'd mark the bottom of that with an "A" or something and keep notes - write down what settings you used for benchy "A".  Then maybe try it with infill speeds at 30mm/sec (not just outer wall).

 

And maybe a 3rd at 25mm/sec.

 

So here's what I think happens - I've seen it in slow motion videos but I could definitely be wrong.  It's printing the outer wall and the pressure is quite high in the nozzle (I think around 500psi which is like 5X a bicycle tire).  It's printing the outer wall and a little just squirts out sideways.  It happens very fast and releives the pressure slightly.  If you print a little cooler and a little slower it's less likely to do this.

 

So I'd try 25mm/sec and lower the printing temp by 5C.  Don't lower the temp much without also slowing it down.  Slowing it down lowers the pressure.  Lowering the temp makes it more viscous and less likely to squirt out the side.  Both things together should hopefully help.

 

 

I could definitely be completely wrong about all this but I think it's an "over pressure squirt".

 

I do know that slowing down the print usually (but not always) solves almost all visual problems.

 

The chimney is extra difficult.  It can fail/slump/blobify due to it never getting a chance to cool down.  The only really good fix is either add much more fan (add a fan in front of your printer blowing on benchy).  MUCH more fan.  Or print a tower (or print 2 benchys), next to benchy.  But I'm not sure what happened with your benchy chimney - maybe you just cancelled the print.

 

3D printing for functional parts (what I do) is great.  3D printing artwork may require a lot more tweaking or alternatively a lot of "post processing" which in your case would mean "sanding".  Or just print slow and cool as hell.  But now your prints take days.  But it may be worth it.

[gr5 2,224]

Another setting that might help a little is to print "outer wall" first.  That way it has the ability to squirt a bit inwards as well. I think that is default but you could double check.  It's somewhere hidden in the 500 or so cura settings.  In PREVIEW mode, after slicing, you can use the vertical slider and then the horizontal slider to see if it prints outer wall before inner wall.

[Xhoax 4]

53 minutes ago, gr5 said:

Benchy is designed to have no support.  So I'd turn that off.  Did you cancel it before the chimney or did it fail?

 

So I'd mark the bottom of that with an "A" or something and keep notes - write down what settings you used for benchy "A".  Then maybe try it with infill speeds at 30mm/sec (not just outer wall).

 

And maybe a 3rd at 25mm/sec.

 

So here's what I think happens - I've seen it in slow motion videos but I could definitely be wrong.  It's printing the outer wall and the pressure is quite high in the nozzle (I think around 500psi which is like 5X a bicycle tire).  It's printing the outer wall and a little just squirts out sideways.  It happens very fast and releives the pressure slightly.  If you print a little cooler and a little slower it's less likely to do this.

 

So I'd try 25mm/sec and lower the printing temp by 5C.  Don't lower the temp much without also slowing it down.  Slowing it down lowers the pressure.  Lowering the temp makes it more viscous and less likely to squirt out the side.  Both things together should hopefully help.

 

 

I could definitely be completely wrong about all this but I think it's an "over pressure squirt".

 

I do know that slowing down the print usually (but not always) solves almost all visual problems.

 

The chimney is extra difficult.  It can fail/slump/blobify due to it never getting a chance to cool down.  The only really good fix is either add much more fan (add a fan in front of your printer blowing on benchy).  MUCH more fan.  Or print a tower (or print 2 benchys), next to benchy.  But I'm not sure what happened with your benchy chimney - maybe you just cancelled the print.

 

3D printing for functional parts (what I do) is great.  3D printing artwork may require a lot more tweaking or alternatively a lot of "post processing" which in your case would mean "sanding".  Or just print slow and cool as hell.  But now your prints take days.  But it may be worth it.

Thanks for the respons.

The chimney broke off, was printed semi good.

 

This this night (few hours) om going to start the benchy b

Print temp 195

No supp

Infillspeed 30

[Xhoax 4]

53 minutes ago, gr5 said:

Another setting that might help a little is to print "outer wall" first.  That way it has the ability to squirt a bit inwards as well. I think that is default but you could double check.  It's somewhere hidden in the 500 or so cura settings.  In PREVIEW mode, after slicing, you can use the vertical slider and then the horizontal slider to see if it prints outer wall before inner wall.

I chanced it, it does inner wall first.

It seems to be hiding the seam better.

Correct me if om wrong

[gr5 2,224]

Let us know which prints you like the most and what settings you changed.  What temp was benchy A?

 

[Xhoax 4]

5 hours ago, gr5 said:

Let us know which prints you like the most and what settings you changed.  What temp was benchy A?

 

Temp was 200, benchy A

 

Here the result of benchy B

Print temp: 195

Infill speed: 30 (like the walls)

 

Overall i think it's  better.

BUT at the window there is a little gap ( that's my problem with the statues we print)

 

With the statues the gaps are visible where the seam is.

Ofcourse here the seam is at an angle, so not really visible.

 

Any tips how i proceed further?

I don't think slowing it down Will make a diffrence.

 

 

 

[Xhoax 4]

4 minutes ago, Xhoax said:

Temp was 200, benchy A

 

Here the result of benchy B

Print temp: 195

Infill speed: 30 (like the walls)

 

Overall i think it's  better.

BUT at the window there is a little gap ( that's my problem with the statues we print)

 

With the statues the gaps are visible where the seam is.

Ofcourse here the seam is at an angle, so not really visible.

 

Any tips how i proceed further?

I don't think slowing it down Will make a diffrence.

 

 

 

In addition

Where the seam is on the front, there is the problem of the gaps.

But very small.

Anyway the problem is there.

 

 

[gr5 2,224]

Okay so completely new problem?  I guess I should have asked you what was the problem with the first model that you wanted to fix.  I guess I'm an idiot for not asking as 5 people look at the same photo and see 5 different things unrelated to each other.

 

So that woman model - did she have gaps?  I saw no gaps.

 

In this final photo you have underextrusion.  A LOT of underextrusion.

 

When you get underextrusion you often want to print with a HIGHER nozzle temperature, lol.  So maybe I was helping you fix the wrong thing?  I was trying to reduce those tiny "bump outs".

 

In the overhead shots around the chimney there is a gap between inner and outer walls and around that cargo locker thing.  Also underextrusion - classic symptoms.

 

For example if you are underextruding by 10% and your line width is 0.4mm for a 0.4mm nozzle then you would expect .04mm gaps looking down and the walls won't look much different: just a bit thinner but those occasional holes in the walls indicate underextrusion.

 

Why is there an extra gap at the port hole in the bow?

 

When you print slower (or stop printing for even 1/10 second) you need less pressure in the head and as you print the pressure eventually (after a second or so) equalizes to a lower pressure.  When you print fast, higher pressure.  When you change speeds you get over or underextrusion.  That's why I like the same print speed for inner, outer and infill.

 

On layer change you stop printing very briefly.  On each non-printing move you stop printing briefly.  You usually get overextrusion when you slow down for a corner and under extrusion when you speed back up.  You have to slow down as you go around that port hole but also there may be a layer change there.

 

What's the fix?  Usually slower printing speeds so you have a more consistent printing speed and more consistent nozzle pressure.  20mm/sec is pretty good.

 

So my suggestion of lower temp may have made things worse - not sure.  Sometimes lower temp helps quality but not if it leads to overall underextrusion.  It can help local spots of underextrusion but if the entire part has underextrusion (as yours seems to do) then you want higher temperature.

 

Also I recommend increasing flow from 100% to 110%.  Go no higher than 110% as then you have new more serious issues including damaging your printer if you get a "head flood".  Or it could just chew up the filament too much in the feeder.

 

I don't like to increase flow normally but since you have underextrusion absolutely everywhere it shouldn't hurt as long as you don't go over 110%.

 

 

PLEASE CLARIFY THOUGH: Did your requirements of what you are trying to fix change part way through?  Did initially you want to fix the bump outs and later want to fix the underextrusion?  Or did you want to fix the underextrusion only the whole time?

 

How is your feeder tension?  Make sure the tension indicator on the feeder is right in the middle.  You want tension at a minimum for TPU and other rubbery filaments and you want it right in the middle for most other filaments like PLA.

[gr5 2,224]

Looking again, there is a LOT of stringing going on as well.  Very confusing.  I would definitely raise the temp to 210 instead.  Lowering the temp may have reduced the bumpouts but made stringing worse. 

 

I just looked at the product recommendations and they say temp 195-220.  That doesn't really tell me much as most PLA recommends about that range.

 

Printing slower always will get you better results.  Lower pressures in the print head.  Less time (relatively) printing at reduced speeds and less time not printing at all (travel moves).

 

I don't know what's going on exactly but even my prints which are functional and don't need to look nice, don't have all this stringy stuff.

[Slashee_the_Cow 409]

51 minutes ago, gr5 said:

Printing slower always will get you better results.

To a point. I printed something so slow one time that almost all of it was overextruded to random degrees that I got this:

When I wanted this:

No, I didn't change the layer height between prints. But I was printing it standing up on its big end (on the right in these photos) because there seemed to be no way I could cleanly remove support holding the tapered end up if I printed it on its side.

5mm diameter at its widest point (the ridge furthest to the right). 29mm high. Tapers down to 2.4mm by the end. To prevent it wobbling (or falling over entirely) a small brim wasn't cutting it (especially because it widens right above the base so the brim isn't supporting a huge amount), so I turned down the speed, acceleration and jerk... a bit too far, as it seems 😕 Fortunately as you can see by the second picture, I eventually got the right balance 🙂 - there were just about another five prototypes between the two. Fortunately the amount of filament it uses can barely be measured so I could burn through as many prototypes as I needed.

(10 Slashee Points to whoever can PM me (don't derail the thread) what it is - you might not have one in your house but it's not a particularly weird or exotic thing)

 

1 hour ago, gr5 said:

I don't know what's going on exactly but even my prints which are functional and don't need to look nice, don't have all this stringy stuff.

So you don't print functional stuff out of PETG or TPU?

(n.b. I have printed functional things out of TPU with no stringing, but only objects that are a single contiguous body with no travel moves or support required)

[gr5 2,224]

That's a special case like Benchy's chimney.  When the part is extra small you get cooling issues if the nozzle is touching the part.  Best fixed by printing a tower next to the print so the part has a few seconds to cool down after each layer.  Ideally place the tower such that one of the fans is blowing on the important part while printing the tower.

 

I'm not sure how printing faster would help this skinny thing: I'm surprised but not shocked.

[Xhoax 4]

6 hours ago, gr5 said:

Okay so completely new problem?  I guess I should have asked you what was the problem with the first model that you wanted to fix.  I guess I'm an idiot for not asking as 5 people look at the same photo and see 5 different things unrelated to each other.

 

So that woman model - did she have gaps?  I saw no gaps.

 

In this final photo you have underextrusion.  A LOT of underextrusion.

 

When you get underextrusion you often want to print with a HIGHER nozzle temperature, lol.  So maybe I was helping you fix the wrong thing?  I was trying to reduce those tiny "bump outs".

 

In the overhead shots around the chimney there is a gap between inner and outer walls and around that cargo locker thing.  Also underextrusion - classic symptoms.

 

For example if you are underextruding by 10% and your line width is 0.4mm for a 0.4mm nozzle then you would expect .04mm gaps looking down and the walls won't look much different: just a bit thinner but those occasional holes in the walls indicate underextrusion.

 

Why is there an extra gap at the port hole in the bow?

 

When you print slower (or stop printing for even 1/10 second) you need less pressure in the head and as you print the pressure eventually (after a second or so) equalizes to a lower pressure.  When you print fast, higher pressure.  When you change speeds you get over or underextrusion.  That's why I like the same print speed for inner, outer and infill.

 

On layer change you stop printing very briefly.  On each non-printing move you stop printing briefly.  You usually get overextrusion when you slow down for a corner and under extrusion when you speed back up.  You have to slow down as you go around that port hole but also there may be a layer change there.

 

What's the fix?  Usually slower printing speeds so you have a more consistent printing speed and more consistent nozzle pressure.  20mm/sec is pretty good.

 

So my suggestion of lower temp may have made things worse - not sure.  Sometimes lower temp helps quality but not if it leads to overall underextrusion.  It can help local spots of underextrusion but if the entire part has underextrusion (as yours seems to do) then you want higher temperature.

 

Also I recommend increasing flow from 100% to 110%.  Go no higher than 110% as then you have new more serious issues including damaging your printer if you get a "head flood".  Or it could just chew up the filament too much in the feeder.

 

I don't like to increase flow normally but since you have underextrusion absolutely everywhere it shouldn't hurt as long as you don't go over 110%.

 

 

PLEASE CLARIFY THOUGH: Did your requirements of what you are trying to fix change part way through?  Did initially you want to fix the bump outs and later want to fix the underextrusion?  Or did you want to fix the underextrusion only the whole time?

 

How is your feeder tension?  Make sure the tension indicator on the feeder is right in the middle.  You want tension at a minimum for TPU and other rubbery filaments and you want it right in the middle for most other filaments like PLA.

I didnt want to fix the bumps

Those we can sand away.

It's the holes om worries about.

 

I don't think it's smart to adapt the 3 steps at once.

 

I start with the temp at 205

And speed a lil slower speed 25

 

Depending on this result we can make more adeptions

[Xhoax 4]

15 hours ago, gr5 said:

Looking again, there is a LOT of stringing going on as well.  Very confusing.  I would definitely raise the temp to 210 instead.  Lowering the temp may have reduced the bumpouts but made stringing worse. 

 

I just looked at the product recommendations and they say temp 195-220.  That doesn't really tell me much as most PLA recommends about that range.

 

Printing slower always will get you better results.  Lower pressures in the print head.  Less time (relatively) printing at reduced speeds and less time not printing at all (travel moves).

 

I don't know what's going on exactly but even my prints which are functional and don't need to look nice, don't have all this stringy stuff.

I think this is not the way. It's worse now.

Temp: 205

All speeds: 25

 

More gaps, now around the entire boat.

More stringing,...

 

What 'special' options should be checked/ unchecked?

 

Maybe printing Faster, specs say 40-100 speed.

 

Idk om guessing heee

 

[gr5 2,224]

Over the window we get what's called "bridging".  Like a bridge across the gap.  This is where Benchy is good at testing bridging.  I don't know if your models will have very much bridging because you need a perfectly horizontal area whereas sculpture doesn't have as many straight lines.

 

Anyway that area looks worse as it bent down.  Probably related to the temperature or speed.
 

Also I see some stringing inside benchy - I'd look at the retraction settings.  I suspect it isn't always retracting.  Sometimes cura will do non-retracting moves if it's a short distance but it looks like you need retraction even for 5mm moves.  Look at the model in PREVIEW mode.  Make sure the line color scheme is set to "line type" and the non extruding moves are blue.  There are light blue and dark blue.  You want only dark blue inside the model (such as infill) and light blue (retracting moves) for the moves inside benchy's wheelhouse.  I don't know what settings will make them all light blue but you can post your project file (do "file" "save project") if you see dark blue lines that are turning into strings and you can't figure out how to make them all retract.

 

I'm not sure how often this will be a problem for organic models either.  So benchy might not be the best test.

 

underextrusion

 

Now to underextrusion.  It looks much better to me. You didn't show the overhead view.  Are the gaps gone in those 2 areas from the overhead view?  I think it was the chimney and the cockpit?

 

From the side, at least in your pictures which aren't as clear as the previous ones, I see only that one horizontal band that has severe underextrusion.  Everywhere else is good!

 

I think this was a one-off situation.  I think maybe you had a filament tangle that fixed itself.  I'd check the filament on the back of the printer.  

 

I think underextrusion looks much better.  Not worse.  Except for that "one off" horizontal band.

 

Another thing is because this is a "filled" filament (viber PLA - I think it has grass?), it's common for the fill to clog a nozzle.  I think a piece of grass was a little too large and clogged the nozzle but it eventually cleared itself.

[Torgeir 259]

Hi @Xhoax.

 

Here's an excerpts from a Viber PLA user.

_____________

 

"Customer Reviews

The fibres in the filament create a very interesting touch sensation on the surface. It feels somewhat like paper and not like plastic at all. Yet, the overall print isn't as clean as one with regular PLA. At every place the print head stops and moves, the fibres leave small strings sticking up."

_____________

 

As this filament is filled with 10% fine chopped elephant grass, it will need "some" more filament feed in order to keep the flow right. Go for the slower speeds and keep the nozzle temperature in the lo end area.

 

Filled filament always add more friction in order to pass through the nozzle.

 

Thanks

Torgeir