New problem 3.01 (Large areas missing)

[DonSch]

I've printed tons with version 2 and have only seen the "missing thin wall" problem. But now, with the latest version, I am wasting a lot of plastic. I noticed where much larger sections of the model is missing. So much is missing that parts are falling off the model.

In the attached picture, the gold number were deeply embedded into the base, but an air gap was printed all around it, and the supports holding the white piece are actually U shaped to so the white part fits down inside the fork. but as you can see, the bottom part of the U and the joint are simply missing. The model is designed to be very strong, but it is falling apart.

[dkightley]

have you checked your print simulation to see if the slicing software is generating voids in the intersections of parts of the 3D model. If so, try clicking the "Separate Connected Surfaces" option in the Mesh dropdown.

If it's what I think it might be, you'll get multiple entries in the "models" list....and the simulation and print will now be okay.

[DonSch]

have you checked your print simulation to see if the slicing software is generating voids in the intersections of parts of the 3D model. If so, try clicking the "Separate Connected Surfaces" option in the Mesh dropdown.

If it's what I think it might be, you'll get multiple entries in the "models" list....and the simulation and print will now be okay.

Where is the "Print Simulation" option, this doesn't appear on the menu. I did "Separate Connected Surfaces" and a list did appear as you said. I have never needed to do this before, is this something I have to remember to click every time I print an assembly made of of multiple parts?

I would think this is something that by default should always be checked if that is what is needed to make the program do what is normally expected.

[DonSch]

Here is the preview of this same model, showing no obvious holes, or gaps in the material.

[dkightley]

This is something I had been plagued with for some time. My CAD package is pants at merging shapes and then a new feature in version 3 of S3D ( the Separate Connected Surfaces function) has saved the day.

Here's a simple model made up of two intersecting cubes:

And here's how it slices....with an air gap where the two cubes intersect:

And here's what it looks like after clicking the Separate Connected Surfaces function:

Its best to use this function whenever you suspect your model may have intersecting meshes.

I remember having exactly the same issue with ReplicatorG....and I cured it by repairing the model with the online Netfabb service. But I don't have to do that now!

[DonSch]

Thank you for the details. I'll be doing some testing on this. The weird thing is I never saw this until version 3.01. In fact I know my parts intersect, When there is not a good mating surface, I generally sink one part into another to make sure there are no spaces between them. This has always worked until now.

[KC_703]

Thanks for pointing out the "Separate Connected Surfaces" from the "Mesh" Menu. This can save some time when designing parts...

I tried printing a figurine with transplanted reindeer antlers... or something like that. And well, the antlers fell out of the figurine. The designer must have added the antlers in Meshmixer or something and S3D sliced as they were designed... the figurine and two antlers. This feature would have come in handy.

[DonSch]

I reprinted the base assembly that I made in Solidworks and used the "separate connected surfaces" as suggested and it gave me the results I expected..

So my question is, if SD3 detects a multi-bodied STL with overlapping surfaces, shouldn't it suggest this setting or turn it on by default?

Now for the bad new, SD3 crashed no less than 5 times while I tried to set this up to print. I ended up making factory files so that I had saved points to reload from after a crash while dealing with many bodies and highly customized supports. There is an angled ramp inside this base part, and an overhang above that, but I didn't want any support on the ramp itself, because it needed to be smooth, so it was a tricky setup.

I generally setup the next part while the printer is printing, but SD3 is so unstable now, I don't dare touch it while it is printing something.

[Tetraodon]

Thank you for pointing out that feature! This happens whenever I use "Join" instead of "Union" in Blender - gave me quite the shock when I printed my first model without thoroughly checking the G-Code preview. Now to test it again so that I can be lazy in how I join parts

[AmyInNH]

Thank you! As a new user, I have to agree with DonSch, that this was not at all obvious nor intuitive to have a default of joined objects perceived as separate and create separate objects. And I never would've guessed "Separate Connected Surfaces" would merge surfaces for printing.

My object(s) are from a MeshMixer union boolean, but I can't remember if I used either Join or Combine afterwards.