My problem is that the printer extrudes too much material between the perimeters (solid infill):

but if the wall doesn’t needs infill, because of its width, it’s perfect:

This over extrusion only occurs at certain wall thicknesses, and I couldn’t fix it. I tried to adjust the solid infill width 0.67->0.4. I tried to set the perimeters/infill overlap 15%->0 , etc.

I usually print with 0.9 extrusion multiplier, and it works in the 99% of the time, except in these situations. I tried to lower it to 0.8, but it just slightly changed the thing.

Is there anybody who could help me?

Thank you very much in advance! :slight_smile:

Regards,

Robert

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What is your slicing software. Each one uses similar, but often different approaches to thin wall behavior.

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I’m using Slic3r.

Step one is to reset the extrusion multiplier to 100% and properly calibrate your extruder.
Next step is measuring the diameter of your filament in at least 3 places and inputting the average into slic3r(if there is a deviation of .1 or more throw it in the trash).

I only use slic3r. In my opinion it is the most versatile and precise but also the least forgiving. If you like options in the form of sliding bars then it’s not for you. In Slic3r everything is measurements and for the most part it does exactly what you tell it to. If it doesn’t, you need to calibrate. Trying to solve calibration issues by tinkering with the extrusion multiplier will always cause as many problems as is solves, if not more.
I’m not saying this will solve your issue, but until you calibrate, diagnosing the problem(as well as using slic3r in general) will be difficult.
-Jesse

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OK, infill in perimeters is a complicated subject, based on the facts that the extruder cannot print less than the width of your extruder, (give or take)

It is not necessarily a fact that your .4mm nozzle will print a width of .4mm, because there is always pressure in your hot end, and therefore likely “bloat” will occur when the filament exits (meaning it expands outward from that pressure). This combined with the fact we ask our printer to adhere layers, by squishing each round filament into an oval when it lays down, mean that in fact usually your width will be more than .4mm. This is easy to test, measure your filament as it extrudes, add a little for squish. My PLA bloats and squishes alot, my extruder prints at .48 out of a .4mm nozzle.

(I DO have to adjust my extrusion multiplier to make sure I get enough material going into the top of my extruder for what I expect to have come out and printed)

But, for the sake of math, lets say that your .4mm extruder prints .4mm. So now the issue is, what to do about a .9mm wall. I can either not print inside the wall where I cannot lay down .1mm inside two .4mm walls (for a total of .9mm), or I can try to put material in there, with a slicer setting. My printer is tuned perfectly, if I do not get material in there, I will have walls that do not touch…

In simplify3d there is a setting under Advanced called Thin wall behavior, that will let you select “only use perimeters for thin walls” or “allow gap fill when necessary” with a percentage. Neither of these are perfect, but you can mess with the % to get close you what you need.

This, combined with the ability to also add a Horizontal Compensation under the Other tab, will get you there. As for Slicer, I am not that good with it to tell you the comparable settings with it.

But think of it this way. How many passes will I have on my wall, based on how much material comes out my extruder end, and how perfect does my hot end print.

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“My PLA bloats and squishes alot, my extruder prints at .48 out of a .4mm nozzle.”
“Dye swell” is a very complex phenomenon and is practically its own branch of science. I was very interested in it for a while but at this point I firmly believe it is irrelevant in FDM printing. The diameter of what you extrude into the air doesn’t matter because
1. It doesn’t change the volume of the material you are extruding. It’s just taking a different shape.
2. Your nozzle is so close to the bed/previous layer that the swell never even happens in practice
3. When you are printing, the material is under tension and being stretched/spread.

“So now the issue is, what to do about a .9mm wall.”
This is one of the reasons I like slic3r. Setting the shell width in mm is silly because, like you explained, it doesn’t represent what the printer can actually do. In slic3r there is no shell/wall width. You set the width of a single perimeter width and then how many you want. This takes more thinking but allows you to get the exact shell thickness you need without gaps.

“I DO have to adjust my extrusion multiplier to make sure I get enough material going into the top of my extruder for what I expect to have come out and printed” “My printer is tuned perfectly…”

http://reprap.org/wiki/Triffid_Hunter’s_Calibration_Guide#E_steps

http://prusaprinters.org/calculator/

^^^Give it a try guys^^^

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Thank you for the informative replies, I will give it a try with the simplify3d program. :slight_smile: I use bq filaments, but I will measure the diameters also.

@MindFuLL, you are correct most of the time, and I am certainly NOT trying to create drama. I do feel that quoting me as if my statements are not accurate or helpful comes off as sarcastic, and there is no place for that here.

I like Simplify3d, You like Slic3r. I believe adjusting extrusion width for the nuances of 3d printing is the way to go, you believe this is not the case. You linked some stuff there that I have all been through before back in the day. I then went with my current approach, and have never looked back.

You believe extrusion width set at 100% is the way to go, I believe die swell, material differences, even things down to the number of teeth on a drive belt, all affect things in such a way that adjusting extrusion width is an acceptable means of resolving, as does a TON of others who have offered their experiences here and elsewhere. I dont believe die swell is complicated, or a science of its own. Its pretty straightforward.

I will of course, continue to state my experiences, and you will continue to state yours. We are both very knowledgeable, and have two acceptable approaches.

And yes, my prints are perfect, and my printer is tuned perfectly. I have done over 400 commercial prints. I have perfect reviews on my hub. Implying otherwise by putting my statements in quotes seems unfair. I have not attacked your approach. Please be mindful of my experience and results as well.

I will be mindful or your approach, and treat you with respect, as you have some fantastic prints, and great reviews as well. But it is important to remember that different slicers utilize different algorithms and approaches. Not everyone uses Slicer, and thus may find my approach, as they have many times in the past, very helpful.

I do understand that this person is using slic3r, and thus may find that my answer is not helpful. Or this person might just make the changes I have suggested, and be very happy. Others reading this issue who use S3D may find my answers useful, or they may find your answers useful.

@Perry_1

Let me first say that I have nothing but respect for you, your work and your contributions here. At the risk of causing conflict when I don’t mean to(well, sometimes I do, but it’s rare), I do tend to be sarcastic from time to time. You say there is no place for it here and maybe you are right, but the subject matter can be a little dry and sometimes I cannot help myself.
When quoting your statements, I truly was not trying to discredit or frame your statements as inaccurate or unhelpful, but in hindsight I certainly see how it could be interpreted that way and I apologize. These were just statements I wanted to comment on with the exception of the last two quotes which I felt illustrated my point that getting a good, quality print and being calibrated are not the same thing.

Like I stated in the past, I’m constantly changing nozzles/materials on my machines and if I had to fiddle with the extrusion multiplier every time, my operation would not be practical. With the exception of die swell(btw, I have a couple dictionary sized books on the subject) all the variables you listed are incorporated into the process of extruder calibration. I have no doubt that your prints are perfect and believe there are probably infinite ways to achieve such a result, but this is the only way I’m aware of to get predictable results when variables are changed. This is very important to me and I concede that this may not be the case for everyone. I’ll be sure to add that disclaimer in the future.

After hearing both our methods, the OP had made an informed decision to try your method, which I totally support. I believe he decided that switching to an entirely new software was easier than making the current one do what he wanted and he’s probably right.

I submit my ideas/opinions/knowledge/experience to help as well as for the purpose of peer review and we would all benefit from more people like you participating in the forum. There is no doubt that we are both passionate about our craft and I believe these exchanges are clearly beneficial to everyone including myself. I look forward to more in the future and will do my best to keep the sarcasm and argumentative tone to a minimum.
-Jesse