http://www.soliforum.com/topic/14283/af … -problems/

I've successfully solved my problems by:

a) following the advice of wardjr and heartless on that thread, i.e. proper extrusion calibration. Thanks guys!
b) using slic3r from upstream, i.e. newer than 1.2.9

my $0.02

fudging numbers just doesn't work. If you want to solve your extrusion problems - do it right.

"Anything worth doing, is worth doing right"

http://reprap.org/wiki/Slic3r#Known_Bugs

http://forums.reprap.org/read.php?262,549909

For the print I am doing right now (raspberry pi case), I do not have large, hollow areas to infill, so I think setting the infill parameter to 0 would be a viable solution for this print, but what about a print like a benchy, where there is need for infill?

Is there a setting that I could ignore small gaps like the 0.08" in your example above?

In your picture you have general over extrusion.  If when you decrease the multiplier to get nice perimeters and infill, you get spaces between the lines on a bottom layer.  This is where you can decrease the extrusion width to close that gap without messing up your calibration.  You can also change extrusion width of infill patterns to achieve nicer surfaces.  This is especially important on 100% infill parts.
I can assume you have a .4 nozzle so this means your general extrusion width will be .48.  I like to use a first layer extrusion width of .36.  Then I set perimeters to .48. Infill widths can range based on what filament and the type of part I am printing but (.44-.52)

I am not certain what "line" you are referring to.  But if it's the space between the outer perimeters,  that's the "infill" section.  Remember that a Slicer is working in multiples of .48 in the X,Y axis.  If a particular area of a print is 2mm wide and you have selected 2 perimeters.  The Slicer is going to create tool paths to fulfill the perimeters first.  This will give 4 lines that add up to 1.92mm.  The Slicer then has to make some assumptions about the remaining .08mm.  If you have selected zero infill it's not a problem as it will just leave a gap between the two sets of perimeters.  If you selected 100% infill it's going to struggle to fill that tiny gap without over extruding.  This is where tweaking that infill extrusion width can come in handy.

I assumed that my steps/mm was correct and did not need correcting since when using CuraEngine, my prints looked okay. As for the filament diameter, I did measure my filament when I concluded I was overextending to see if the Dia was greater than 1.75, but it was just slightly smaller, so I concluded that lowering the filament diameter would only increase the true amount of filament extruded, making my issue worse. Do these seem like reasonable conclusions to make on what is/is not my problem?

I know the extrusion multiplier is probably designed as a final fudge factor, but in the event that the steps/mm is actually off, and the filament diameter is close but not spot on, is there an issue with compensating with the extrusion width?

1. have you calibrated your extruder steps/mm? this is where you start. If you ask for 100mms of filament to be fed in, you need to get 100mms of filament... for more info, read this: http://northwoods3d.weebly.com/blog/fil … ion-part-1

2. Have you calibrated your filament? average diameter, etc?
No two spools of filament will be the same, and it is very rare to have one that is exactly 1.75mm in diameter. For a slicing program to produce accurate results, it needs accurate information. Also, the extrusion multiplier should be calculated for a given spool of filament - not randomly changed. For more information on this aspect, see here: http://northwoods3d.weebly.com/blog/-fl … coming-out

Good calibration routines are essential to producing good prints.

Since this print, I have printed half a dozen Benchy's. My belief is that I was over-extruding because of the issue I posted about, as well as marks on the top fill from my nozzle dragging through it. I changed only the extrusion multiplier to 0.9, then 0.8, then 0.7 before noticing major gaps between the toolpath on the "deck" of the Benchy. Looking back, I can see small gaps in the 0.8 extrusion multiplier print as well. I am currently printing at 0.85, but I still see small gaps. I think 0.9 is what I need to be using for extrusion multiplier.

As for my issue though, I completely believe the solution is between the extrusion widths page and possibly the number of vertical shells, This is where I have been toying around, but with very little success. My best results so far have been seen by reducing the widths to 0.4, but from what I am reading, it is not advised to use an extrusion width lower than about 120% of the nozzle diameter, so I'm kind of confused there. Do you have a suggestion for settings to use here for a 0.4mm nozzle?

I'm new to the scene, so forgive me if I have misdiagnosed my issue. I stole one of my pictures because I think it shows what I'm talking about even more than my own picture. My picture is of the pink print. There is a bead running down the center of the top of the wall, best seen in the u̶p̶p̶e̶r̶ ̶r̶i̶g̶h̶t̶ ̶h̶a̶n̶d̶ ̶c̶o̶r̶n̶e̶r̶ upper left hand corner of the image. The stolen image I believe also shows this same trait. It's seems to me like the exterior of the walls are being printed, then the center is being over-filled.

What I have done so far:
- tuned down the extrusion multiplier until there are small gaps in the flats of my print.

Using Slic3r, Repetier Host, with a Da Vinci 1.0

Any ideas?

EDIT: Looks like the orientation of the image is different than I expected. The issue looks like what I would describe as a weld bead down the center of the wall.