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SoliForum - 3D Printing Community → XYZ Printing DaVinci → 1mm vertical surfaces too thick.
If you are measuring output indtead of input then this would explain most of your problems.
Ok, I just noticed something weird that could explain why I'm getting some unreasonable numbers. As mentioned earlier, I marked 100mm of filament from where it enters the extruder tube, told it to extrude 100 (using manual controls in octoprint), measured the difference, and it came up 7mm short! This put my new esteps at about 106.45. I went back into repetier, changed the eeprom value, reset the printer (just in case) and confirmed it had the new value. Since I was already in repetier, I decided to just repeat the test from there.
This time when I told it to extrude 100mm, it overshot by quite a bit, probably close to 7mm, but hard to measure. I also noticed that the diameter of the post-extruded filament was much more even, consistent, and thinner. The filament coming out with repetier measures at about .5mm, and coming out when I tell it to extrude with octoprint, it is more like .8mm (nozzle is .4).
Checking the gcode when each tells it to extrude, I see this:
Octoprint: G1 E100 F300
Repetier: G1 E100 F120*22
That seems to match up with the printer configuration in octoprint, which has the extrusion rate set to 300mm/min.
Now for prints, I don't *think* this should matter, right? Because it's the slicer that's going to generate the gcode that gets sent to the printer. But for calibration, it seems to matter quite a bit. So for purposes of calibration, should I just be sending a raw "G1 E100" regardless of which tool I use? Or should I specify a feedrate, and if so, what is a more reasonable feedrate to specify than 300?
If you are measuring output indtead of input then this would explain most of your problems.
No, sorry for not being more specific - I am definitely measuring input when trying this calibration, but see my message above. I think the feedrate in different tools is the source of some of my strange results for calibration at least.
For the purpose of calibration you should use the host and slicer you plan to use all the time. If you must use other "tools" then make sure all variable from tool to tool is set the same.
So, since repetier was yielding much more sensible results with the 120 feedrate, I used that for calibration and ended up... right back where I started at 99! So using that, I printed the single perimeter box and adjusted the extrusion multiplier in slic3r until I got it to .48, and set the default extrusion width to .48 as well. Now with this, I tried a test print, from repetier, of a frame with 1mm edges again, and still came out with 1.4-1.5mm walls. 
So that reminds me of a comment I read further up in this thread...
Example: you want to print a wall that is designed 1mm thick but (if using a .40 nozzle) your extrusion width is .48. If using 1 perimeter (total .96mm since there's 2, an inner and outer) the slicer will have to decide how to fill the remaining .04. But since the extrusion width is .48,,, well you get the point. Alternately if using 2 perimeters (that ends up being 4 extrusions) or a total of 1.92mm in extrusion width. The slicer has to calculate a solution even though the math doesn't add up. The real solution is to design around this issues (on small areas of a print) using multiples of your extrusion width.
All that being said, it is rare that a designer takes this into consideration. Fortunately for us slicers do a pretty good job at coming up with a solution.
So am I just doing something that's impossible? I've seen this work from another printer, but it was a part that someone ordered from someone on 3dhubs, and I don't know which they used so I have no details about the printer it was done on. But I do know that the resulting measurements were 1.0mm +/- 0.01
Are you using a model for your test that has a simgle wall? Or are you using a solid model and telling the slicer to print a single perimeter/wall with no top and no infill?
There is a difference and you should be using a solide cube with mentioned slicer settings.
Calibration aside, you should post up the file with the 1mm wall and some pictures of your prints.
You'd be amazed at the information we can dig out of a good picture.
Are you using a model for your test that has a simgle wall? Or are you using a solid model and telling the slicer to print a single perimeter/wall with no top and no infill?
There is a difference and you should be using a solide cube with mentioned slicer settings.
For the calibration test where I'm trying to get a single .48mm perimeter, yes - I'm using a solid cube with 1 perimeter, 0 infill, 0 top. This is working perfectly now - with my esteps calibrated (right back where I started) and .9 extruder multiplier set in slic3r I get .48mm for the single perimeter.
The original thing I was trying to achieve that started this thread though, was a 'frame' of sorts, that is 1mm all the way around. For that, I have a different object I'm using to test it, and it's still coming out quite a bit thicker than 1mm.
Calibration aside, you should post up the file with the 1mm wall and some pictures of your prints.
You'd be amazed at the information we can dig out of a good picture.
Sure, it's just as I described, just 1mm on all 4 sides. Stl is attached, and here are a couple of pictures.
Here's another angle:
So am I just doing something that's impossible?
The quick answer to this is no. This is an issue of understanding how Slic3r functions and how to set up the profile to yield the proper results.
Carl is spot on in that you calibrate with a designed solid cube and make the slicer print it as a single wall hallow cube with no top. All the calibration in the world won't matter if you don't then use the same host and slicer as the one you did the calibration with.
pwlars wrote:So am I just doing something that's impossible?
The quick answer to this is no. This is an issue of understanding how Slic3r functions and how to set up the profile to yield the proper results.
Carl is spot on in that you calibrate with a designed solid cube and make the slicer print it as a single wall hallow cube with no top. All the calibration in the world won't matter if you don't then use the same host and slicer as the one you did the calibration with.
Yes, that's exactly what I did, and the print that I just posted pictures with was done *all* done in repetier, with calibration done from repetier as well.
I'm not seeing the .stl
And your settings are? # of perimeters and infill settings? Also layer height
Also, for completeness, my measurements of the 4 walls in the above print (taken near the top, so I exclude any possible deformation at the base):
1.41, 1.32, 1.45, 1.36
We will get you there, it looks like there is a lot of mechanical play in that print. Is it possible that your carriage is sloppy or the hotend itself?
We will get you there, it looks like there is a lot of mechanical play in that print. Is it possible that your carriage is sloppy or the hotend itself?
Not as far as I can tell. I've done the usual recommendations of shimming/gluing the bushings on the guiderod for the bed, I've tensioned the belts on both the x and y axis, checked that the idler on the left carriage spins freely, and checked that the carriages on both sides are aligned. This was all part of trying to get circles to be *really* round. It's definitely improved from where it was, but still not perfect. When I print rectangular objects though, they usually come out very close to the intended dimensions. I didn't want to bring up the circles in this thread though, so as not to distract from the main issue I'm trying to resolve right now.
I'm glad to hear that printing something 1mm wide *should* be possible, but I find it a bit confounding that I can print a 20x20 cube that comes out very precise, but printing something 1mmx20mm comes out closer to 1.4x20. Looking at the paths, I did notice that the infill for the 1mm sided object (50%, but probably doesn't matter since there's not much space to infill) pretty much seems to just print a straight line down the middle between the .48mm perimeters on each side. Is it possible that this effectively pushes them out a bit, causing the oversizing?
I drew up what I think you have there and even at 100% infill Slic3r doesn't try and fill in between the perimeters.
Here's a picture very close up of what the side of your print should look like. This is at .3mm layer height with a .60 nozzle. This is to help you visualize what I am saying about mechanical slop.
If you get me your .stl (it didn't show up) and settings (just perimeters, infill and layer height) I will try and duplicate your print to help troubleshoot the cause of your problems.
Ok, let's try a different way to send you the file: http://expirebox.com/download/ffc62db67 … b1bd3.html
I'm using 2mm layer height, .4 nozzle diameter, 1 perimeter, 50% infill.
I'm not really sure what your image is showing me, but the reason I was thinking the infill would be an issue is that if the perimeter walls come out to .48mm, then there would be a .04mm gap between them unless it does *something*. When I show the layers in slic3r, I distinctly see 3 paths at each layer - one for each perimeter and 1 in the middle to fill in the gap that would exist there.
Just to help put that other picture into perspective. 
all the images are showing is the smoothness compared to your image. I resized them so hopefully that helps. Not sure why imgur made the first ones so huge.
This is the result I get when I slice it at 50% and 100%. What version of Slic3r are you running?
I did get the .stl loaded when you select a file you need to also select upload file afterwards. It is sometimes a bit finicky.
This is the result I get when I slice it at 50% and 100%. What version of Slic3r are you running?
1.2.9 from Ubuntu Xenial. The three separate paths are easier to see when I look at the layers tab.
So what happens when you specify 1 perimeter with no infill? (Just as a test)
It should be a quick print. I have no doubts that If I had a machine with a .40 nozzle in it and printed what my slicer generated, it would come out almost perfect.
Or alternately draw up the same rectangle with a .96 wall thickness and see what that print looks like.
I've noticed this same issue. The newer version of Slic3r in my experience will add an additional perimeter when you're dealing with a shelled object. I've only succeeded in getting 1 or 3 perimeters, but never just the 2 that I want. I suspect it's a bug, because it happens even when "generate extra perimeters" is disabled. It can really screw with your head, and it definitely messes up dimensions.
So what happens when you specify 1 perimeter with no infill? (Just as a test)
It should be a quick print. I have no doubts that If I had a machine with a .40 nozzle in it and printed what my slicer generated, it would come out almost perfect.Or alternately draw up the same rectangle with a .96 wall thickness and see what that print looks like.
Interesting, I made a similar model with .96 wall thickness all the way around. If I do *any* infill, it still shows a third path. Perhaps because of infill overlap? I have this currently set to 15%. As a quick test though, I did try setting the infill to 0 with this model, confirmed there were only 2 paths, one for each perimeter. The measurements I'm getting all the way around are almost exactly 1.00mm! This is a neat trick, but it makes me think even more that I'm going to need to print something much thicker to get consistent results. I also tried one at 1.5mm and it comes out to more like 1.8mm all the way around. I suspect as that thickness gets higher, I'll get better results, but that's not really what I'm shooting for here.
SoliForum - 3D Printing Community → XYZ Printing DaVinci → 1mm vertical surfaces too thick.
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