Why does a 1mm wall result in 3 traces using a printing width of 0.5mm ?

Hi - I am currently trying to print a case which features very small walls on the sides (1mm). But the walls always get too thick, 1.5-1.6 mm apparently.

I decided to dig into the problem and created a 1x15x5 mm stand-alone wall (cp. problem_01.png) and imported this to Repetier and sliced it with Slic3er.

This results in a printing path of 3 lines in width (2x perimeter and 1x infill trace) -> cp. problem_02.png. My settings for the print width are all set to 0.5mm in Slic3er -> Print Settings -> Advanced (cp. problem_03.png).

I also tried to uncheck "Extra perimeters if needed" and "Detect thin walls" in Slic3er -> Print Settings -> Layers and Perimeters.

But nothing helped...

Why does Slic3er create 3 traces instead of 2 traces in this case ?

Edited 1 time(s). Last edit at 11/01/2016 08:26AM by salocinx.

I sometimes get similar problems. Try either making the wall 1.01mm or the extrusion width 0.49mm and see what happens - this often works for me.

Dave

Hi Dave

Thanks for the quick reply. Setting extrusion width to 0.49mm does not help, still the same problem. But when setting the wall width to 0.95mm, it does indeed calculate only the perimeter, 2x 0.5mm without the inner trace.

But changing/faking my model, which is quite complex, for the only purpose of this Slic3er issue is somehow painful :-/ Isn't there any setting to control/override that particular behaviour ?

In that case try setting the extrusion width to 0.51mm. Should have a similar effect to narrowing the wall width.

Dave

I have ran into the same problem. Lots of extra material around the part.

Took me 2 days to figure out what was wrong. I was doing a 1mm wall, it put a .4mm perimeter on outside and inside then put a line in between. There is only .2mm gap and the nozzle is .4mm. If I manual make the width .5 then all is good.

I think the system should be able to handle this correctly.

Gap fill is broken in 1.29, it overfills. Set the gap fill speed to 0 to turn it off. It's fixed in 1.30-dev.

along the same lines I am having trouble with perimeter calculations also.

I would like to understand how slic3r works so that I can configure the print settings to get what I want. At this point when I make changes to perimeter widths I don't get the results that I would expect.


for testing I made a simple 1mm wall and used 0.5mm for all the settings in slicer.

Why does one end of the wall look correct and not the other?

The image is quite small, can you provide a closeup of the corner in question? And maybe attach the .stl file to play with?

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o_lampe
The image is quite small, can you provide a closeup of the corner in question? And maybe attach the .stl file to play with?

Attached is the STL file.

I played with it a while longer and it appears to be a Repetier problem. I put it on the Slic3r plate and it looked ok so disregard the question for now.