How to print single walled test part.

I am trying to print this single walled test piece but no matter what I do Skeinforge insists on making it double walled. I am using a layer thickness of .4mm and perimeter width over thickness of 1.8. So far I have tried setting all three "extra shells" settings in fill to zero as well as disabling all plug-ins except carve, speed, and dimension. I am not sure how else to calibrate flow rate and feed rate without being able to print a single walled piece.

It also seems that "maximum z feed rate" in limit is not obeyed while printing the raft. Is there another setting for max z feed rate in raft or am I making some other mistake.

Finally, is it possible to not generate the m101 and m103 commands an the beginning and end of each layer? I am using Teacup firmware which requires 5d gcode and I am letting skeinforge manage filament retraction between layers.

Any help is appreciated.

What is your steps_per_mm setting for the Z axis on the teacup? Teacup does not like values greater 1000 and will ignore the maximum z feed rate value if the the steps_per_mm is greater than 1000.

The steps/mm aren't that high, around 160, but you're right the feed rate limit in the firmware should catch it. I may have the z axes feed rate set to high in firmware, I'll have to double check that. Regardless, I can see in the gcode that skeinforge uses the travel feed rate when moving the z axes while building the raft.

Quote
spaztik
I am trying to print this single walled test piece but no matter what I do Skeinforge insists on making it double walled. I am
...
Finally, is it possible to not generate the m101 and m103 commands an the beginning and end of each layer?
...

I couldn't get Skeinforge 35 to create a single walled gcode with that stl file either no matter what I did. So, I just made my own STL file in Solidworks with a wall thickness of 0.6 to match my setting (layer thickness 0.4, perimeter over thickness 1.5, width 0.6 mm) and it finally generated a single walled object. I've attached the STL file here.

You need to create or edit a replace.csv file in your alterations folder.

M101	;M101
M103	;M103

Thanks. Those both worked.

You're welcome. I just tried this today with Skeinforge 040 and used it to adjust the flow rate. Surprisingly, the flow rate values are very large! It's about 40x larger than the feed rate. With 035, it was less than 2x feed rate. Not sure why there's such a large difference.

brnrd Wrote:
-------------------------------------------------------
> You're welcome. I just tried this today with
> Skeinforge 040 and used it to adjust the flow
> rate. Surprisingly, the flow rate values are very
> large! It's about 40x larger than the feed rate.
> With 035, it was less than 2x feed rate. Not sure
> why there's such a large difference.

The Dimension plugin changed for skeinforge 40. You need to change your firmware e_steps_per_mm to steps per mm of feedstock, rather than steps per mm of extrudate. Also, you should have your flowrate and feedrate set to the same value. Then measure your feedstock diameter and input that, and the filament packing ratio for ABS should be about 0.85 and for PLA should be 1.0. Also, you'll need to change the extruder retraction speed, as that is now in mm/s of feedstock as well, so it should be much smaller than it was before. Same goes for retraction distance.

The whole idea is that now skeinforge knows how much plastic is going into your extruder, and therefore knows how much is coming out. Also, you won't have to adjust your firmware or the skeinforge settings when using different nozzle sizes.

I just spent the past couple hours figuring that all out, can you tell? I had to track back from [fabmetheus.blogspot.com] to a post on a different blog to figure out what was going on.

Edited 3 time(s). Last edit at 03/02/2011 01:32AM by NewPerfection.

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