Simplify3D User Forum

See attached: on this small overhangs (about 0,8mm) the support is not correctly triggered.
When entering a smaller value than the standard 2,5mm for the support posts (1,0 is the minimum) there are some supports in the gCode but not fully correct

...and here the settings as I couldn't attach a 4th screenshot

I came here to report something similar. A whole section of my print (which I pretty much designed to be difficult to print even with supports and in the preview I could tell that (1) parts of it were printing hanging in the air and (2) the support material is hanging in the air in some places.

STL included if you want to try yourself.

Generally if you have an overhang of less than 1mm you don't need support, as the weight of the plastic doesn't pull it down, and it'd be very difficult to deal with support in the tiny area. It's also likely smaller than the horizontal clearance area for support in S3D.

I say generally because it depends on the specific case. For example, when printing a vertical wall with writing extruded 1mm out of it, you don't need support. But if you have (for example) a large vertical overhang (e.g. a screw head, for a screw printed vertically) which might need support, or at least need careful slicing.

yes another thing to think about and add to what laird said is you have to have some type of horizontal offset from the part itself or the support will bond to it. i usually set that to .3-.5mm. so figure the offset then consider a single width of your extrusion is aprox .5 which comes out to a total of close to 1mm. the support is basically doing nothing anyway.

laird wrote:Generally if you have an overhang of less than 1mm you don't need support, as the weight of the plastic doesn't pull it down, and it'd be very difficult to deal with support in the tiny area. It's also likely smaller than the horizontal clearance area for support in S3D.I say generally because it depends on the specific case. For example, when printing a vertical wall with writing extruded 1mm out of it, you don't need support. But if you have (for example) a large vertical overhang (e.g. a screw head, for a screw printed vertically) which might need support, or at least need careful slicing.

You can't print this model properly without support on thise ribs - I tried but failed!
If you like I'll re-model this part (I got it from a customer and would model just this difficult part) so that you can fail to print it too

jimc wrote:yes another thing to think about and add to what laird said is you have to have some type of horizontal offset from the part itself or the support will bond to it. i usually set that to .3-.5mm. so figure the offset then consider a single width of your extrusion is aprox .5 which comes out to a total of close to 1mm. the support is basically doing nothing anyway.

I do print my support with just 0,1mm distance and it works perfect: but as it seems I cannot do this in Simplify (works good with Slic3r and Kisslicer)

laird wrote:Generally if you have an overhang of less than 1mm you don't need support, as the weight of the plastic doesn't pull it down, and it'd be very difficult to deal with support in the tiny area. It's also likely smaller than the horizontal clearance area for support in S3D.

As mentioned I will post the model: I can NOT rotate the part as it is just a section of a larger part (rotate the stl so that the flat square surface is on the bottom)
I remodeled it that's why the dimensions are not equal to the model I posted before.

Feel free to try to print it perfectly (0,1mm layers).

Looking at your model, I don't see how S3D's support could work for this model, given how I think S3D's support is generated.

Given that, perhaps human-generated supports would be better? I find that human-generated support is always better than automatic, because human judgement is a lot more efficient than software. It's more time-consuming, of course.

One thing I can think of is that you could add some thin vertical, radial walls through the outer part of the threads, perhaps 16 would dd? You'd need to cut/break them off the threads, but it'd be way easier than what auto-generated supports would do. If you only have to print this once, it might not be worth the effort, admittedly...

laird wrote:Looking at your model, I don't see how S3D's support could work for this model, given how I think S3D's support is generated.
Given that, perhaps human-generated supports would be better?

Definitely and I also did that already.
BUT: Free Slicers as Kisslicer and Slic3r CAN DO this, but not a $140 software

MLWorx wrote:

laird wrote:Looking at your model, I don't see how S3D's support could work for this model, given how I think S3D's support is generated.
Given that, perhaps human-generated supports would be better?

Definitely and I also did that already.
BUT: Free Slicers as Kisslicer and Slic3r CAN DO this, but not a $140 software

Really? It's a pretty tricky part. What do they generate? Those little threads, with the flat bottoms of the thread, aren't easy to support...