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Is anyone else having this issue? Please for Marvin’s dignity let me know how you fixed this.

Printing my 1st Marvin at 100 Microns. After printing this twice and checking my slicer settings, I think based on the model there it no way to avoid printing “his biz”.

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Because no matter what , at 100 microns, you’re going to get an island at the bottom of his body. (see slicer view of 100 micron layer height)

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When I printed the 200 micron version I was able to adjust the layers so that the 1st layer which included the bottom of is body was bridging the gap between the legs and he was printed very properly with no hint of impropriety. (see slicer view of 200 micron layer height)

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Well done 200 Micron Marvin, YOU can go out in public, we’ll have to leave your 100 Micron brother at home for now. He might make small children start crying. LOL

5 Likes
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The only way to print floating islands (which is what the central portion you are seeing) is to put support from the built platform up to it.

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Are you printing the 100 micron Marvin at the same speed as the 200 Micron? And what is your filament you are using?

Some suggestions to try:

1) Print slower

2) Increase flow rate. The faster you print with smaller layer sizes, sometimes increasing the flow rate can help.

3) Get external fan to blow air gently on design or upgrade your current fan. I see some blobage that indicates you may be printing slightly to hot for such a small design. Also I see some indicators that some layers were not cool enough before the next layer was put down. On my printrbot simple metal I have a small fan (http://www.amazon.com/gp/product/B002OJN250?psc=1&redirect=true&ref\_=oh\_aui\_detailpage\_o02\_s00) propped up in front of it that I turn on after the first couple of layers are laid down in addition to the printer’s fan.

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thanks for the trouble shooting. but I think the issue is with the model generating that floating island at 100 Microns, at 200 Microns you can adjust it so the 1st layer of the body is a span between his legs.

I think you’re right about printing too hot at 100microns. I am using colorFabb pla-pha and should probably be printing at ~195C this print was done at 210C. My other printer settings were:

speed 30mm/s

flow 100%

fans on full after 1st layer

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@MOARobotics do you generate support when you print the 100micron marvin, or would you just trim that off after the print?

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It’s not the model. The island showing up between his feet is actually something Cura does to all designs. Basically it’s showing the center of the model and should not be causing the issue. Worst case scenario is that the version of cura you are using could be affecting the print and maybe try a different cura version or another slicer software to rule that out? I changed over to simplify3d a while ago because Cura’s slicer algorithms got worst and worst with each new version released that I couldn’t use the program anymore with my printrbot.

In your case though my bet is on the flow rate and the temperature. Your printer could be having difficulty printing that area because it can’t get enough filament out when using 100 microns in such a small area. Try bumping the flow rate from 100 to 110.

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I generate support but just between the legs, and under the ears, with a 300 micron separation; the support separates pretty easily, and I can usually clean the surface up with my fingernail. The others point out some good points about speed and temperature, but based on your pictures it definitely looks like support because your print looks pretty good to me otherwise.

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1 Like
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thanks, this makes sense. based on the geometry of the model I don’t think any slicer has a choice but to create that island. Support is the way to deal with that.

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Is support “allowed” on my first test print marvin? There are many things I can do to address this issue but I want to make sure I’m in compliance and meeting the requirements of 3D hubs.

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You have to remove the support. Marvin can be printed with 0 (zero) support :slight_smile:

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This problem is not caused by support structures. It is a result of the layer between the legs being printed in space with no connecting filament to the leg components.

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I did a test in cura, with the marvin sinked 0.25 mm (cut off object bottom) and the image at layer 24 is simillar with the one posted here.