Holes on walls printing ABS

[maxamaral]

Hi guys,

I´m new on the Rostock printing, and I´m testing several different parameters. When printing single perimeter walls (even 3 perimeters), I´m getting those holes, as if there is not enough filament to fill these gaps.

[img]https://photos-3.dropbox.com/t/0/AACzmk ... e=1024x768[/img]

What is the main reason for that?

Some info:
Seemecnc Gold ABS
layer_height = 0.2
; perimeters = 1
; perimeter_speed = 20
; infill_speed = 20
; travel_speed = 150
; nozzle_diameter = 0.55
; filament_diameter = 1.75
; extrusion_multiplier = 1
; perimeters extrusion width = 0.55mm
; infill extrusion width = 0.55mm
; solid infill extrusion width = 0.55mm
; top infill extrusion width = 0.55mm
; first layer extrusion width = 0.60mm

Thanks a lot,

Max

[cambo3d]

bad filament maybe

[September]

I think I remember reading something about this and that the cause could be moister in the air and/or on the filament.


Besides that out of curiosity for myself, what's the melting point range for your ABS and what temperature are you running at?

[maxamaral]

Thanks guys for the replies, both are very helpful. I have indeed popping sounds, and I'm running ABS at 230C. However, I have tried lower temps, but the gaps persist, and with lower temps it seems I starve on filament. I still melts at 220C, since I can extrude it, but on the job it seems to starve.

Anyway, I'll try both things - replace with a sealed filament roll (the one I'm using is opened for about a week or 2) and also try to descrease temp with this new filament.

Thanks a lot,

Max

[September]

No worries and here's the URL I read about the moister http://www.protoparadigm.com/blog/2013/ ... -printing/

I've been working around the same temps 230C and have tried lower with my ABS, which has a melting point between 210 and 250. I haven't seen anything like what you've had nor had any popping sounds in my prints. I'm still be working on calibration, I don't think I have it quite right yet.

Also I'm using a different filament, Blue ABS from bilbycnc.com.au, only because it's more local to me and doesn't take as long to post.

[JohnStack]

I would agree but you might consider slowing your print speed down and/or bumping up your feed rate.

Contrary to that notion, unfortunately is that on certain prints, I get gaps in the same places. That might indicate come thing like a coefficient between the shape, the heat, the speed, and the feed rate.

[RichW]

I've noticed, on a fan duct I'm trying to print that slic3r makes some strange moves (rapid traverse moves with small dots of printing) at some points in the run and actually makes holes. I don't know if there is some artifact in the geometry that sets it off because I am not too familiar with Open SCAD. I mean to try the latest upgrade of slic3r before moving on to the other options.