Changing Layer Heights Affects Extrusion Widths

Hello all,

I am not new to these forums by any means but my account is no longer active or something. Its been a while since i have posted anything.
Anyways here are my settings:

Printer of my own design(ill share it here once my write up is completed on it.) This printer is based somewhat loosely on my(now disassembled) prusa.
Nozzle diameter: .5mm
Filament: 3mm
Material: PLA
Tool Chain: Solidworks(mostly), netfab if needed, then slic3r V.9.9 and pronterface as my host.

I have all axes and Extruder steps/mm calibrated correctly. (triple checked)

So here is a little background to my issue:
I am sick of the inside diameters of holes coming out too small. It happened on my older prusa as well as the new one.
So i did a little digging and found this post: http://forums.reprap.org/read.php?263,273929
It states that having a lower later height will allow for holes to be printed to the correct size. So i decided to give it a try.
I was printing with .4 layer height before and went to .2mm and found a difference in quality but also noticed a few other things as well.
When i had my layer height at .4mm, the gcode stated that my perimeter width would be .53mm and it was really close to that. Most of the other widths like infill and solid layers were also at .53mm
When i set the layer height to .2mm, the gcode states that my perimeter width would be .83, which it measured out to correctly, but also had .3mm for top infill, and some other value for infill.
This change seems to affect my dimensions when i compare calibration objects between the 2 layer heights. On one layer height, somethings are better, and some worse between the 2 values.

I guess my issue is whether this is expected outputs from slicer for my settings or if there is something else at play here.
I can post the gcode on here once i get home.
I have not tried to print a calibration object with the goal of calibrating top shell infill with the .2mm layer height, but i am worried that i will not have enough fill, because even with my .4mm layer height and .53 top shell infill width, there were gaps in the fill so i will need to increase the top shell multiplier but have not had a chance to fully calibrated that yet for .4mm layer heights.

I have printed the calibration test piece from that post i linked to earlier at both layer heights, ill post the measurements for comparison on here when i get home as well. also ill include the STL.

If you need any more information, please ask and i will get it for you.
Also, any suggested models to print that may help determine if there is an issue here.

Thanks all.
-Erik

I was part of that thread you linked to. Slic3r in it's current form will NOT give you proper hole sizes no matter the settings. If you notice lower in the thread myself and Sublime posted results from using Kisslicer instead of Slic3r.

Yes, changing layer height will affect size. Think of it like this, the extruder spits out a cylinder, it consists of a certain mass if you squeeze it in one direction it gets bigger in the other direction kind of like a rubber O-ring. So the smaller the layer height the more it's squeezed and thus affects the overall dimension but it's minuscule in reality. A piece printed with .1mm layer height is going to be fatter than one at .4mm layer height but you will never get the right size today using Slic3r. I did put in a bug report for it (I could not find one already and was amazed no one put it in before) it's been that way since the first slic3r I used (0.7.5?!?).

I was the one that suggested printing at lower layer heights help. But the main thing about was I was suggesting was to NOT use slic3r's automatic extrusion width calculations because they are backwards of what they should be ( I tried explaining this to the developers of Slicer and was told it was fixed but they actually made it worse ). The lower the layer the narrower the path should be, NOT wider as slic3r does. That is why I suggested using my calculator to calculate the correct extrusion width and then set it manually (which in the latest release RC1 causes paths to be in the wrong location).

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I just found this [github.com] and am testing this now. Maybe it will actually solve the issue.

I just checked out your calculator. Interesting I will have to try that as well.

Thanks for the replies guys.
I read through your posts from that other thread.
I have read that several people have had issues with slic3r hole sizes and am suprised that there wasnt a bug request for it.

Ill try KISSlicer at some point(maybe tonight) and ill use your calc sublime. You had mentioned it several times in that other thread and i should have heeded your advice. I will try it and let you know what i find.

That link from github explains a few things but in my original post i mentioned that no matter what slic3rs widths are, my single wall tests are spot on. I think my largest error was .03mm in wall thickness.
Its too bad he closed that bug thread as i have done exactly what he said to do and i STILL have issues with hole size.

Not to knock on the devs at slic3r, i like the software a lot. But i think they are trying to do too much for the user and it hurts accuracy.
I used to use skein but that was before my printer was in storage for a few months. I figured i would see if there was any thing better and faster to slice. and slic3r was it, except for my hole issue...

ill give KISSilcer a try using the Sublimes calc.

Ill let you know what i find.

Thanks guys,
Erik

Hey Sublime,

Question for you really quick.
Im tryin out KISS and i was wondering what your setting for skin thickness is set to.
Default is .8 and extrusion width is .5
I am changing the e width to .53 as per your calc. good work. Bookmarked indeed.

I am going to experiment with a thin wall test and measure it and see what happens,
I am assuming a single wall will be the extrusion width, and anything with infill will have the skin thickness.

your thoughts?
-E

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Erik G
Hey Sublime,

Question for you really quick.
Im tryin out KISS and i was wondering what your setting for skin thickness is set to.
Default is .8 and extrusion width is .5
I am changing the e width to .53 as per your calc. good work. Bookmarked indeed.

I am going to experiment with a thin wall test and measure it and see what happens,
I am assuming a single wall will be the extrusion width, and anything with infill will have the skin thickness.

your thoughts?
-E

Skin thickness is a funny setting since it sets the top and bottom thickness as well as the minimum wall thickness. So if you have two perimeters at 0.53mm wide I would set the skin thickness to 0.9 or 1. If it is set to a value higher than the width times the perimeter count it will add squiggly infill around the inside to make up the extra wall thickness which is not the best.

Also when I say the extrusion is too wide is not a bug where Slic3r puts out too much plastic for the width it has decided to use. But rather one where it simply decides to make too wide of extrusions. So that is why in your tests the single wall width turns out as specified. Its just that that width is wrong to get accurate prints. One way to think of it is to imagine two long strips of clay on a table. One really wide like Slic3r tries to extrude and one narrower like i am suggesting. If you bend both of those strips of clay 90 degrees you will see the extra material on the inside of the corner gets squished inwards. The wider the strip the more material inside of the center line so the more it causes the hole to get smaller.

If you would like to see all of my settings you can download the Tantillus profiles from Tantillus.org on the downloads page.

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I just did a bunch of test prints following the calibration in that link I posted and no matter what I changed it to the hole size varied very little (almost none). I have concluded that slicer does not do a correct tool path and all of those settings just control the amount of plastic extruded.

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Sublime
Also when I say the extrusion is too wide is not a bug where Slic3r puts out too much plastic for the width it has decided to use....

That makes sense. I guess i hadnt thought if it in quite those terms. I am going to use the clay example when explaining this to others.

As far as the skin thickness goes: if i do a singe wall thickness part, should this be set to my extruder width?
(edit you mentioned 2 perimeters, set your skin to .9 or 1, your talking about the number of loops setting correct?
for three perimeters i would set skin to 1.4-1.5, if i am under standing this correctly?

@Tmorris:
I feel your pain buddy. It frustrating to no end. Im really going to give KISS a chance, but its behaving oddly.

New development:
When i slice this part in KISS, i get gaps between the print. Ill attach my gcode so you can have a look at what the output of KISS was. Its just a thin wall test... really odd.It happens with other single wall models from thingiverse too. so its not just my model.

If there is a way to export my KISS settings so you can have a look at them, i will do so.
also, I had to cut the gcode down but i think you will get the idea.

(edit 2) And lastly there is no equivalent of skirt in KISS is there?

Thanks
-E

Edited 2 time(s). Last edit at 12/05/2013 11:44PM by Erik G.

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Erik G

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Sublime
Also when I say the extrusion is too wide is not a bug where Slic3r puts out too much plastic for the width it has decided to use....

That makes sense. I guess i hadnt thought if it in quite those terms. I am going to use the clay example when explaining this to others.

As far as the skin thickness goes: if i do a singe wall thickness part, should this be set to my extruder width?
(edit you mentioned 2 perimeters, set your skin to .9 or 1, your talking about the number of loops setting correct?
for three perimeters i would set skin to 1.4-1.5, if i am under standing this correctly?

Yes for a single wall you would set it to the extrusion width or smaller. Just remember it effects the top and bottom thickness as well so you can not have a thin wall with a thick top and bottom. For three yes you could have it that thick but only if you want the top and bottom that thick. If not just set it to the thickness you want the top and bottom (as long as its less then the loops times the extrusion width).

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Erik G
New development:
When i slice this part in KISS, i get gaps between the print. Ill attach my gcode so you can have a look at what the output of KISS was. Its just a thin wall test... really odd.It happens with other single wall models from thingiverse too. so its not just my model.

That type of model is not really good for testing since it can be thinner than the extrusion width which enables a feature in Kisslicer called crowning. Kisslicer will print the thin wall cube you tried but it first prints all the parts that are as wide as the extrusion width and then it goes back and prints the parts that are thinner (crowning) which can give poor results on thin walls. Instead to print a single wall print you would take a solid cube and set the loops to 1, skin thickness to 0 and the infill to hollow. Then it will print a single wall, this is also how you slice the stretch bracelet.

Also I notice in the gcode you are using Relative extrusion (which I prefer and recommend). But Kisslicer does not automatically insert the M command to set the firmware to Relative extrusion. So you either need to manually enter it in the printer/prefix tab or have it set in the firmware config. If you have Kisslicer set to Relative extrusion and the firmware is set to Absolute extrusion it will not ouput enough plastic and it will fail.

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Erik G
If there is a way to export my KISS settings so you can have a look at them, i will do so.

Yes they are saved in the same folder as the executable.

If we are going to keep discussing Kisslicer I would suggest starting a thread in this form section [forums.reprap.org] where it has been discussed before.

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Before you make too hasty decisions on which Slicer to use and which not, there is a lot of information out there you may consider. You are making a lot of noise on not quite simple problems which may influence a lot of good peoples effort to give you (for free) some advanced programs you are not able to make yourself. And that is a pity :-(.

Some of you may have seen this before and for others it could inspire to some rethinking of the problems you meet.
Take a look on this written by a person that has made a lot of good thinking related to these not simple problems:
http://hydraraptor.blogspot.dk/2011/02/polyholes.html

Think about it and also which other parameters that may have influence on endresult, like calibration, viscosity of material, temperature, extruder, use of fan , bad habits etc...
and when you have come to some conclusions you may contribute to the developers of some really good ideas on how to make these programs even better by suggestions on how to do that.

Edited 1 time(s). Last edit at 12/06/2013 12:22PM by justcurious.

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justcurious
Before you make too hasty decisions on which Slicer to use and which not, there is a lot of information out there you may consider. You are making a lot of noise on not quite simple problems which may influence a lot of good peoples effort to give you (for free) some advanced programs you are not able to make yourself. And that is a pity :-(.

Some of you may have seen this before and for others it could inspire to some rethinking of the problems you meet.
Take a look on this written by a person that has made a lot of good thinking related to these not simple problems:
http://hydraraptor.blogspot.dk/2011/02/polyholes.html

Think about it and also which other parameters that may have influence on endresult, like calibration, viscosity of material, temperature, extruder, use of fan , bad habits etc...
and when you have come to some conclusions you may contribute to the developers of some really good ideas on how to make these programs even better by suggestions on how to do that.

Nophead reduces the flow rate for perimeters to achieve what he does with the polyhole test and that is only possible with Skeinforge making his test irrelevant to all slicers except Skeinforge using his settings for perimeter flow rate. See here [github.com] where he says

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Nophead
I use my own maths with SF because you input the flow rate versus feed rate and I don't set them the same for the outline.

So if you want to extrude big fat paths like he does and have the holes turn out correct you must reduce the perimeter flow to make them turn out smaller then they are calculated to be (under extruded). This is actually more fudging then what I propose where you set the numbers correctly to produce paths that do not exhibit the issue of crowding the hole.

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re Sublime
Nophead writes this as a start to his guidance, which is the reason he has worked on what to do about it.:
"When Reprap machines print holes they tend to come out undersized, even if the linear dimensions of an object are spot on.
There are several effects that all make holes smaller than they should be: -"

I have deep respect for the work you have made to better understand how extruders are working, but I am not sure that it is the best way to guide the majority of users to get the best results, but that is just my opinion, so you should of course keep up the good work.

I have no knowledge on how much of this information is included into different slicers or just ignored, but that could be a start to get verified. Nophead suggest in his article on how to compensate in the cad program, that is another way of doing it. i would be happy if all of my programs could take care of these problems, but they obviously don't and you suggestions are a way of getting around. They did not solve all my problems, but certainly showed a way of getting better and developers may learn a few things here (i)
I do not have very lonng experience on this playground, but I try to have an open mind for progress. Sofar some of my problems are with circles that seems to be under meaure but that goes for inner and outer circles just like Nophead is suggesting and I need a lot of more testing to conclude anything valid yet.

Edited 1 time(s). Last edit at 12/06/2013 01:01PM by justcurious.

@Just Curious, You are right, perhaps i am making too much noise. I have done a fair amount of digging and reading and research and everything i have found points to Slic3r having an issue with extrusion width especially with holes. I have calibrated my printer per Slic3rs recommendations and according to them that is all i need to do in order to get correctly dimensioned parts. I do like Slic3r and want it to work, its close... Also what is your tool chain?

@ Sublime, that is really solid info. I will look into trying the single walled part as you described versus designing a part to do that. I had noticed that the wall thickness of a few parts are exactly as you described, too thin. I look forward to setting up the print settings as you suggest and trying the single wall test that way. and ill ask you too, what is your tool chain?

Thanks for all the advice. Ill play around this weekend and hopefully find a solution to my needs.
-E

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justcurious
re Sublime
Nophead writes this as a start to his guidance, which is the reason he has worked on what to do about it.:
"When Reprap machines print holes they tend to come out undersized, even if the linear dimensions of an object are spot on.
There are several effects that all make holes smaller than they should be: -"

I have deep respect for the work you have made to better understand how extruders are working, but I am not sure that it is the best way to guide the majority of users to get the best results, but that is just my opinion, so you should of course keep up the good work.

I have no knowledge on how much of this information is included into different slicers or just ignored, but that could be a start to get verified. Nophead suggest in his article on how to compensate in the cad program, that is another way of doing it. i would be happy if all of my programs could take care of these problems, but they obviously don't and you suggestions are a way of getting around. They did not solve all my problems, but certainly showed a way of getting better and developers may learn a few things here (i)
I do not have very lonng experience on this playground, but I try to have an open mind for progress. Sofar some of my problems are with circles that seems to be under meaure but that goes for inner and outer circles just like Nophead is suggesting and I need a lot of more testing to conclude anything valid yet.

I was not trying to argue just pointing out what Nophead wrote on the matter was when the only usable slicer was Skeinforge and even then he had to make adjustments in the flow rate of the perimeter to make them turn out. So in the end his results are skewed due to not actually letting the flow rate remain the same as the rest of the part (which mathematically it should be). If he had left the flow rate the same then it would have actually had the same results as you get with Slic3r and Kisslicer and Cura and all the other slicers when using wide paths and tall layers. This problem comes up with all slicers [kisslicer.com] (recent Kisslicer post about holes to small) and yet others get the correct sizes. This only leaves the possibility of being user settings or the machine, not the slicer itself. In that Kisslicer post PenskyGuy says that Kisslicer makes the holes wrong by putting the path on the wrong side of the models perimeter. But that is not the case and he can easily be proven wrong by opening the gcode file and looking at the coordinates where you will see the holes are being generated the hole size plus the extrusion width which is exactly as it should be (In that Slic3r thread Alexj asks to be shown a gcode file with evidence of them being in the wrong place too and no one can because Slic3r also creates the paths in the correct place.

So in the end Nopheads method of reducing the flow rate is similar to mine where we extrude a smaller path. Except with mine you reduce the path width over the entire model (which has added benefits like less blobs). But with mine to reduce the path width you must reduce the layer height because for proper extrusion there is a maximum/minimum width you can print at for any given layer height.

Also neither mine nor Nopheads work is used in any of the slicers. We both use slicers that allow you to enter the correct value manually without causing bugs to appear (currently not possible with Slic3r). But also note I never said for anyone to use another slicer as I feel this issue is not a Slic3r specific one (except its automatic width calculation which very few experienced users use) but rather one with the settings being used.

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Erik G
what is your tool chain?
-E

I use Blender to model.
Kisslicer to slice.
SDcard to print.

I will try netfabb cloud to fix things sometimes but it will often add issues by trying to patch the model.

Also note that Kisslicer does not like any errors in the model. It can produce strange defects if the model has errors. To get rid of those errors it is a manual process in a mesh modeller which is not always easy. Also I use Kisslicer not because of the holes but because it is bug free and produces clean paths. I used to use Slic3r until I got tired of wasting filament and time on bugs in new versions that were not there back at version 0.7.2b.

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So it seems this issue we are all having with hole sizes and extrusion widths have been around for a while. with different theories on why and how to fix it. Very interesting and challenging which is one thing i like about 3d printing with an open source printer. Oh the fun of it all.

I will try some things tonight with KISS, i am still getting familiar with it.

Ill let you all know what i find.

-E

I just wrote a post processing script for Kisslicer that will allow you to change the flow rates of each extrusion type independently. It just looks for the comments stating when each extrusion type starts (perimeter, loops, solid infill, sparse infill, support, support interface) and injects a M221 S code which changes the flow rate in Marlin in percentages. The script is written in lua so you will need lua installed or an executable copy in the same folder as the script and the slicer. You will also need to add this

lua "Flow_rate.lua" " < FILE > " 
without the spaces around the word FILE (the forum removes the < FILE and > if the spaces are not there

to the post-process field in the firmware tab of Kisslicer. Then at the top of the script file you will see where the variables are set to adjust the flow rate of each extrusion type, default 100%.

This should allow you to seamlessly use other slicers like Nophead uses Skeinforge by reducing the flow rate of the perimeter and then the polyhole test should work the same.

Note: The script creates a second gcode file marked processed.

It would work with Slic3r as well if anyone would like to make the changes.

Edited 2 time(s). Last edit at 12/06/2013 04:46PM by Sublime.

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Very cool. Ill have a look through that, once i get through the back log of other things i need to do.
I noticed that KISS comments what is going on in the Gcode, which i assume is how you are able to parse the gcode to change flow rates.
How would this be done in something like slic3r? Looking at dimensions? hmm.. ill have to ponder that for a while.
Ill give your script a try at some point and if i like the results from KISS i may try to get it to work with slic3r.
unless i end up liking KISS better which may just happen.

Cheers, Happy friday all.
-Erik

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Erik G
Very cool. Ill have a look through that, once i get through the back log of other things i need to do.
I noticed that KISS comments what is going on in the Gcode, which i assume is how you are able to parse the gcode to change flow rates.
How would this be done in something like slic3r? Looking at dimensions? hmm.. ill have to ponder that for a while.
Ill give your script a try at some point and if i like the results from KISS i may try to get it to work with slic3r.
unless i end up liking KISS better which may just happen.

Cheers, Happy friday all.
-Erik

Yes I use Kisslicers comments to find each path type starting point. I know Slic3r can have comments and Cura uses the same system for commenting so once someone has changed the code it should work for both Slic3r and Cura. I am not sure if you need to enable comments in either of them first but you do in Kisslicer.

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Here is an updated script that uses Nopheads equation to calculate the perimeter flow rate from the layer height and extrusion width. Just enter the layer height and extrusion width at the top of the script and it will set the perimeter flow rate for you.

You can read more here [forums.reprap.org]

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I created a github repo for it and added parsing for Cura gcode as well. [github.com]

Sic3r parsing will be harder since it adds the comments to the end of every single line of code.

Edited 2 time(s). Last edit at 12/07/2013 03:42AM by Sublime.

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Eric G.
what is your tool chain?
Basically I use this and others if needed, but try to keep it simple:
Autodesk/123D Design=>Slic3R/Kissslicer/NetFabb=>Repetier Host/Marlin FW/Ordbot HW.

By not using a pro CAD sw I do not have facilities to influence quality of optimixing STL outputs for mesh count, but there may be a way of doing this, maybe in Netfabb, but did not find it yet.

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Sublime
I created a github repo for it and added parsing for Cura gcode as well. [github.com]
Sic3r parsing will be harder since it adds the comments to the end of every single line of code.

I am impressed of your creativity to find new ways, and I hope I find some time to follow your inspiring effort and maybe this could be a way of making influence to developers with this :-).
i had never heard of LURA but why not?
Slic3r has already (1.0) possibily of dedicated flow settings for different extrusion types and together with speed settings for this, would that not give you the same opportunities as your script?

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justcurious

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Sublime
I created a github repo for it and added parsing for Cura gcode as well. [github.com]
Sic3r parsing will be harder since it adds the comments to the end of every single line of code.

I am impressed of your creativity to find new ways, and I hope I find some time to follow your inspiring effort and maybe this could be a way of making influence to developers with this :-).
i had never heard of LURA but why not?
Slic3r has already (1.0) possibily of dedicated flow settings for different extrusion types and together with speed settings for this, would that not give you the same opportunities as your script?

I just went through all the setting in Slic3r rc1 in expert mode and it only allows you to adjust the flow for bridges and for the entire print. I could not find anywhere it let you adjust the flow independently for each path type. You can adjust the extrusion size but that effects the size of the extrusion as well as where it is placed. With this script it actually allows you to slightly under extrude. It does this because the outer extruded path is not a square extrusion equal to the height and width but rather it has a rounded outer edge that will protrude past the edge. So Nophead wrote an equation that calculates the difference between the volume of a square extrusion and a rounded extrusion on the outside and reduces the flow to create a rounded extrusion that lines up with the edge calculated for a square extrusion. This is how Nophead prints with Skeinforge which is the only software he gets accurate results with.

Also it is written in lua because I had a script already written to adjust the fan speeds so it was easy to modify for this.

Edited 1 time(s). Last edit at 12/07/2013 11:39AM by Sublime.

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Sublime

I just went through all the setting in Slic3r rc1 in expert mode and it only allows you to adjust the flow for bridges and for the entire print. I could not find anywhere it let you adjust the flow independently for each path type. You can adjust the extrusion size but that effects the size of the extrusion as well as where it is placed. With this script it actually allows you to slightly under extrude. It does this because the outer extruded path is not a square extrusion equal to the height and width but rather it has a rounded outer edge that will protrude past the edge. So Nophead wrote an equation that calculates the difference between the volume of a square extrusion and a rounded extrusion on the outside and reduces the flow to create a rounded extrusion that lines up with the edge calculated for a square extrusion. This is how Nophead prints with Skeinforge which is the only software he gets accurate results with.

I am not sure I understand your explanation of difference between change of Extrusion Width vs flow. Any extrusion has a profile of a rounded rectangle which does not change with extrusion width and the change of flow with change of extrusion width is a rectangle sized of layerheightXchange of extrusion width as long as speed is not changed. I thought that the whole idea of changing extrusion width was to change the path slightly to enter a zone more compatible to the original cad file? iDo you think that slicers have an error because they calculate flow with rectangles only?

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justcurious

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Sublime

I just went through all the setting in Slic3r rc1 in expert mode and it only allows you to adjust the flow for bridges and for the entire print. I could not find anywhere it let you adjust the flow independently for each path type. You can adjust the extrusion size but that effects the size of the extrusion as well as where it is placed. With this script it actually allows you to slightly under extrude. It does this because the outer extruded path is not a square extrusion equal to the height and width but rather it has a rounded outer edge that will protrude past the edge. So Nophead wrote an equation that calculates the difference between the volume of a square extrusion and a rounded extrusion on the outside and reduces the flow to create a rounded extrusion that lines up with the edge calculated for a square extrusion. This is how Nophead prints with Skeinforge which is the only software he gets accurate results with.

I am not sure I understand your explanation of difference between change of Extrusion Width vs flow. Any extrusion has a profile of a rounded rectangle which does not change with extrusion width and the change of flow with change of extrusion width is a rectangle sized of layerheightXchange of extrusion width as long as speed is not changed. I thought that the whole idea of changing extrusion width was to change the path slightly to enter a zone more compatible to the original cad file? iDo you think that slicers have an error because they calculate flow with rectangles only?

Ok when you change the extrusion width in the slicer it insets the path from the edge half of the extrusion width without taking into account the rounded edge (or at least all slicers I have used which does not include this newest Slic3r), instead they assume a square profile. This method of reducing the flow keeps the path in the location of the square profile as calculated by the slicer but then reduces the flow rate for the perimeter to extrude a narrower path equal to the width of the square path but with rounded edges based on an equation by Nophead.

I personally do not think this is a bug in the slicers since it does not cause the issue the same way with low layers and narrow extrusions and is only really and issue with certain printing styles. If you look at an Ultimaker or Tantillus that uses lower layers and always have a high degree of accuracy regardless of the slicer used you have to come to the conclusion that it is the settings or the hardware. If the machine is calibrated to move the correct distance as requested then it can not be hardware and that only leaves settings. Also a square profile is correct for paths that have another path next to it like solid infill or multiple loops.

So I guess for a program that defaults to high layers and wide extrusions this could be considered a bug. I wrote this script to try and allow others to print the way that is often promoted in RepRap (but I do not agree with) while reducing the hundreds of complaints that things are inaccurate. I have tried to promote the lower layers and narrower extrusions but am met with a lot of that is not how so and so does it or that is not what the wiki says or no look at Nophead polyhole test. I have given evidence that the lower, narrower method has less issues with inaccuracy and a lot of people use it but it is not the mainstream method. The issue of holes too small comes up far too often to not try and solve it somehow, either my method or Nopheads since those are the only two I know of. If anyone else has another method I would love to hear about it and maybe we can combine them all into one super method.

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huh...it sure is complicated stuff and I am afraid there is not one single answer.
You have proved that your method is working, that is for sure, but I am also quite sute that somehow you have used every inch of knowledge from your machine and experience with materials to get there and most of us may never get that far :-(.
I jumped into this discussion because I am also tired of all the complaints about these issues without finding good answers. It is a problem that far too many parameters change when people are tweaking these things, so probably you will never find two conditions being the same and that makes it hard to discuss .
I also feel that developers get frustrated because most of these complaints never gets fully documented to be registered as an actually bug, so it is very hard to actually do something about it as a sw problem.
Nevertheless i think it is vital to keep uncovering the actual problem to get to an understanding on how to change things if possible, and your effort thas been amazing with the experience and insight you have obtained. it would be fine if some people involved in the slicing sw industry would enter the arena and enlight some of the mistakes expressed or alternatively could we as users try harder to make some descriptions of what we see as not too perfect sw and togethe we might find a way where complaints could be a rare case instead.

Quote
justcurious
huh...it sure is complicated stuff and I am afraid there is not one single answer.
You have proved that your method is working, that is for sure, but I am also quite sute that somehow you have used every inch of knowledge from your machine and experience with materials to get there and most of us may never get that far :-(.
I jumped into this discussion because I am also tired of all the complaints about these issues without finding good answers. It is a problem that far too many parameters change when people are tweaking these things, so probably you will never find two conditions being the same and that makes it hard to discuss .
I also feel that developers get frustrated because most of these complaints never gets fully documented to be registered as an actually bug, so it is very hard to actually do something about it as a sw problem.
Nevertheless i think it is vital to keep uncovering the actual problem to get to an understanding on how to change things if possible, and your effort thas been amazing with the experience and insight you have obtained. it would be fine if some people involved in the slicing sw industry would enter the arena and enlight some of the mistakes expressed or alternatively could we as users try harder to make some descriptions of what we see as not too perfect sw and togethe we might find a way where complaints could be a rare case instead.

I think you are totally correct. I also think the answer to getting it to happen automatically in the software is to prove what works and what doesn't. If anyone tries the script and find it is the answer to their problem or a combination with my lower/narrower method is the answer we can get more to try it.

One mechanical thing that may actually help the precision of an Ultimaker, Tantillus, Delta bot is the hysteresis in the bowden tube. I know this sounds crazy as it's the reason people say not to use one. The hysteresis seems to smooth out the flow and create a constant extrusion of plastic. Where as a direct extruder speeds up and slows down with every segment of extrusion as a result of the short distance between the drive wheel and the hotend combined with the lower acceleration speeds used with the heavier extruder.

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I just updated the script file itself to use Windows style line ending to try and solve a possible Windows compatibility issue.

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FFF Settings Calculator	Gcode post processors	Geometric Object Deposition Tool Blog
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