Spiral vase making start and stop point offset

[blddk]

While printing a cylinder with Slic3r 0.9.10b's spiral vase function I noticed my printer starting and stopping some times where the layer change would have been. Turns out there are some gaps, and on other layers they overlap instead.

Gaps: Overlaps:

G-Code: https://www.dropbox.com/s/uf72nvg3zxuglgv/cylinder_100_30.g

[SystemsGuy]

Appear to have captured the same in a friends print - will try and reproduce myself as well.

Config and generated G-Code https://docs.google.com/file/d/0B_cm90NTsO8VcnVZaVpGWDlhYXM/edit?usp=sharing

[SystemsGuy]

From 0.9.11-dev

[blddk]

Turns out, the problem is not only with vase spiral enabled.

[t00tie]

I got this too when testing 0.9.11-dev Starts and stops, reverses all the time, lots of retraction. None of this was expected. It definitely doesn't move as if it was a spiral vase.

Not sure if it's a bug but slicing took "forever" (Process took 14 minutes and 46.048 seconds) even though extrusion width is the same as openscad wall width.

Openscad source: $fn=333; difference(){ cylinder(r=50, h=35); translate([0,0,-1]) cylinder(r=49.5, h=37); }

stl: https://dl.dropboxusercontent.com/u/96201881/bugs/vase.stl gcode: https://dl.dropboxusercontent.com/u/96201881/bugs/vase.gcode config: https://dl.dropboxusercontent.com/u/96201881/bugs/config-0.9.11-dev.ini

0.9.11-dev from github, prusa i2, Sprinter, pronterface, ubuntu 12.04 LTS

[alranel]

@t00tie, to avoid triggering the medial axis algorithm which is responsible for collapsing islands into single traces, your walls should be thick twice the extrusion width.

An easier way to make vases is to just make them solid: http://slic3r.org/blog/tip-printing-vases

[alranel]

I fixed this! @blddk, the gap you see is the usual clipping that is performed at the end of each loop for preventing nozzle to extrude twice on the same point (start/end of the loop). That makes totally sense in normal mode, but it does not in spiral vase which is what I just fixed.