I can't seem to make small features slice without gaps...

Have questions or comments about Simplify3D, Slic3r, Cura, Reptier, etc? Or wondering about which CAD software to use...discuss it here...
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tlucas
Posts: 2
Joined: Mon Feb 01, 2016 9:35 am

I can't seem to make small features slice without gaps...

Post by tlucas » Thu May 19, 2016 8:17 am

Trying to slice a fancy iPhone4S case I designed (see
skull supports new.stl
(9.8 MiB) Downloaded 419 times
). It has many small 0.4mm to 1mm wide features in the first several layers that I can't seem to get to slice properly. Tried Cura, slic3r/RepetierHost w/slic3r (slic3r just hangs when attempting this), and Simplify 3D. Tweaking the advanced options doesn't seem to do it. The "only follow mesh surface" option in Cura gets the features to show up, but no infill isn't going to cut it. The model was completed with Autodesk Fusion 360, and it appears to be solid -- passes all checks, etc.

Could someone else try it out? I've attached my Simplify FFF so you can replicate it exactly (
tlucas-PETG-fine.fff
(28.55 KiB) Downloaded 436 times
). It'd be much appreciated :)

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Jules
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Joined: Wed Jan 21, 2015 1:36 am

Re: I can't seem to make small features slice without gaps..

Post by Jules » Thu May 19, 2016 3:56 pm

Hmmmn...Beautiful file. :)

But....you're trying to print an awful lot of Thin Walls.

0.4 mm wide is one layer width, and there are a lot of areas in the file that are smaller than that. If S3D can't fit a full layer into the space allotted when it is printing Thin Walls, it drops the path. (Probably Slic3r and Cura too)

You need to either redesign the floral swirly stuff with wider walls, (at least 2 thread thicknesses) or use a smaller nozzle to print that.
(If you do use a smaller nozzle - that beautiful lace effect is going to break when you breathe on it, so be very careful with it.)

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zemlin
Posts: 467
Joined: Thu Feb 04, 2016 9:32 pm
Location: Indianapolis, Indiana

Re: I can't seem to make small features slice without gaps..

Post by zemlin » Thu May 19, 2016 5:17 pm

I looked to see what it would do with a .25mm nozzle - and that still isn't small enough.
Beautiful design work, for sure - but I don't think FDM is the right process for something as delicate as that.
We just got a Form 2 SLA machine at work - probably a good candidate for a part like this.

jsc
Posts: 1864
Joined: Thu Apr 10, 2014 4:00 am

Re: I can't seem to make small features slice without gaps..

Post by jsc » Thu May 19, 2016 5:48 pm

Yes, as Jules said, if a wall is less than your thread width, S3D and others will leave it out.

Also, for slightly thicker walls, if it puts in the perimeters and finds that the gap between is less than a thread width, it can't fill it in, so (say) walls between .8mm and 1.2mm will always have a gap inside because there is just no space to fit three threads.

You can't make lace with a glue gun.

tlucas
Posts: 2
Joined: Mon Feb 01, 2016 9:35 am

Re: I can't seem to make small features slice without gaps..

Post by tlucas » Thu May 19, 2016 6:51 pm

Thanks guys, appreciate the help. I will thicken it up a bit, maybe even put the skull on the right way up this time ;) . I did try printing the Cura "mesh surface only" option just to see what the details would look like with my .35 nozzles, and can now see exactly where the details will and will not work. http://i.imgur.com/lhnwbJZ.png Try to ignore the blobs -- it's PETG doing single-wall bridges on the other side -- never going to work :) .

Zemlin, the Form 2 does look like a beautiful machine. Maybe next year...

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