Welcome! Log In Create A New Profile

Advanced

What causes little holes in the surface?

Posted by fsamir 
Forum List Message List New Topic
fsamir
What causes little holes in the surface?
January 15, 2013 06:25PM
Hi reprapers,

sometimes I get this little holes in the surface finishing. Any idea on waht could be causing it?
Slic3r settings:
ABS 1.75mm
Extruder: 225C
Speed: 30mm/s
MG Prusa Mendel





Edited 1 time(s). Last edit at 01/15/2013 06:26PM by fsamir.

Cheers,
Franklin Dattein
Reply Quote
VDX
Re: What causes little holes in the surface?
January 16, 2013 01:57AM
... with a single top shell this ist most likely caused by the extruding parameters with low/critical amount of plastic or layer height.

Try changing your settings to maybe three top shells, so the underlying holes will be closed by the last layers ...

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]
Reply Quote
fsamir
Re: What causes little holes in the surface?
January 16, 2013 02:24AM
Thanks. However, this printing has 3 shells both on vertical and horizontal layers, but the problem is only happening on the top ones.
Any other parameter that I need to provide in order to give you guys more clues?
Reply Quote
VDX
Re: What causes little holes in the surface?
January 16, 2013 02:38AM
... there should be some parameters for 'bridging', that could help ...

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]
Reply Quote
fsamir
Re: What causes little holes in the surface?
January 16, 2013 02:42AM
Layer height: 0.2mm
Top solid infill: 30mm/s
Bridges: 40mm/s
BRidge flow ration: 1.3

Cheers,
Franklin Dattein
Reply Quote
Polygonhell
Re: What causes little holes in the surface?
January 16, 2013 01:55PM
It's 1 or 2 things, either your W/T ratio is too low to bridge the sparse infil, though you should be fine at 0.2mm and width matching whatever your nozzle size is.
Or you are under extruding slightly during the fill, either from slipping filament, or similar.
Reply Quote
fsamir
Re: What causes little holes in the surface?
January 16, 2013 07:24PM
I think my issue is slipping filament. I noticed it is getting harder to push filament manually over the extruder, which tells me it is time to cleanup the extruder.

Thanks.
Reply Quote
JazzyB
Re: What causes little holes in the surface?
January 20, 2013 05:12PM
I get the same issue - once I fixed it by tightening the idler on the extruder - got the same problem last night but didn't notice till this morning so I didn't get the chance to correct it, but I've tightened them again and will see how it goes next print!

Perhaps try this - I also think it may be slipping filament, seems to be the issue that causes it for me!
Reply Quote
fsamir
Re: What causes little holes in the surface?
January 20, 2013 05:28PM
It was a combination of loose idler (I swetched from 1.75mm to 1.65mm filament) and the new spool holder that I printed which is hard to spin.

Cheers,
Franklin Dattein
Reply Quote
JazzyB
Re: What causes little holes in the surface?
January 20, 2013 10:01PM
Awesome ;-) yep - everytime I've had those "holes" It's been a filament-feeding problem... not enough grip, or as you say, too tight on the spool holder...

Glad u fixed it!
Reply Quote
Speedsoda
Re: What causes little holes in the surface?
January 21, 2013 05:31AM
I see you solved the problem, but there can be different causes to this:
* Too little plastic being extruded, as in your case. Could be caused by incorrect printer settings, jams or poor grip.
* Also, overheating. If the first top layer is still soft and hot when the hotend makes the next pass, it could be ripped up due to the fact that it's so fragile. Solved with a fan.
Reply Quote
Newer Topic Older Topic
Sorry, only registered users may post in this forum.

Click here to login