slic3r insists on printing tubes very sslloowwllyy

clipfromgcode.rtf centraltube.stl config.ini config2.ini
Any idea why Slic3r 1.1.7 won't print tubes faster than very slowly? Attached is two versions of the config.ini, neither seems to change the print speed at all, using the slower of the two. The same setting will zoom through a more normal shape. The .stl for a 10cm long tube 1.5cm in diameter is attached, this is now 1hr 20min into the print and is only at 72mm in height. I switched all the speeds to 120 just to see what print time was estimated, and again, the duration was more or less the same, it was faster, but not for such a large speed increase. A piece of the gcode from the current print is also attached, just the openeing and a peice from layer 2. The same happened when I printed larger spools at 3.5cmm in diameter, very very slow print. Accurate, but so long....
Thanks for any help and insights your group wisdom can enlighten me with!!

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Socrates ~ The Amsterdamman
slic3r-1.2.9

Are you printing the file direct from the SD card? If not, the problem may be that the PC isn't sending data to the printer fast enough - especially if you are using the RRP firmware + web interface rather than mine or zpl's.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

yes, I copy the files onto the SD using the RRP web interface and print from the SD. Was surprised how the speed changes don't seem to be reflected for the tubular shapes. Other more complex models with holes will make the fast sounds of the nozzle zooming around the hole three times, and on much smaller diameter holes. So it seems odd.

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Socrates ~ The Amsterdamman
slic3r-1.2.9

Looking at the gcode, for the perimeters it is commanding extrusion at only 800mm/min and then 600mm/min, which is only 13mm/sec. and then 10mm/sec. I suspect you have either the acceleration limits or the speed for "small perimeters" set lower than you want in slic3r.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I had the same issue, and discovered that it was caused by my setting for minimum layer time in Slic3r - if a layer would normally take less time than that setting to print, Slic3r slows down all the moves so that the layer will take longer. As DC42 says, it could also be your "small perimeters" speed setting.

Dave

is it the "slow down if layer print time is below (set to 30)"?? And is this to allow the previous print layer to cool? If so what is a good minimum? That would seem a important delay, or the part will slump I assume. When I made similar models in KISSlicer it printed very fast and did not seem to have issues from the previous layer being too hot still.
You guys rock again!

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Socrates ~ The Amsterdamman
slic3r-1.2.9

Yes, that's the setting I referred to. With the setting you give, you'll get a slow-down on any layer that would otherwise take less than 30 seconds to print. It is meant to allow a cool-down time, but I find it is not that helpful because on small sections the nozzle never moves far from one point for the entire layer and so its proximity keeps the column molten - slowing down doesn't help. In that case you need to place a sacrificial column outside of the main print so it forces the extruder to move to-and-fro, giving your part time to cool while the hotend is away printing the sacrificial column. Slowing down the speed that the layer is printed only helps for sections that are reasonably large - for small sections it makes the problem worse. I should think 5 or 10 seconds would be sufficient in such cases, but best disable it (set to 0) unless you are having problems with a particular print.

Dave

Thanks Dave! Wasn't sure if I changed that, but it says 30sec is default. I could print two object of similar heights as well, The tubes are used as four tube sets. Makes sense why the print time estimate wouldn't change regardless of what speeds I used. Pronterface gives 1hr45min estimate old settings 20min with new disabled minimum layer time! Seems you are right! Thanks again Dave!!

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Socrates ~ The Amsterdamman
slic3r-1.2.9