Why so much support on 90° Angles in 2.6.1

[kmanstudios 1,120]

There seems to be a lot of wasted support on some of this stuff like so:

Basic model with 90° tower. On right hand side is overhang, expect support there, but not on left side:

Go to Layer view and get a ton of support where there is no overhang. Am I missing something?

[IRobertI 520]

It could be "Support horizontal expansion" causing this. By default the value is fairly high (and can help make better prints), try lowering it and see if the extra support goes away.

[kmanstudios 1,120]

Hokey Smokes IRobertI-Man! It woiked!

Many thanks for such a simple thing. I had no idea it would cause that effect

Shaves some time off too!

Edited July 2, 2017 by Guest

[ultiarjan 1,223]

still pretty strange horizontal expansion is causing this ridiculous amount of support where non is need. I would expect it to only "expand" from placed where support is needed....

[neotko 1,417]

still pretty strange horizontal expansion is causing this ridiculous amount of support where non is need. I would expect it to only "expand" from placed where support is needed....

I think that's because that other cura option to connect supports, so it expands and also connect near supports, making a huge support with even more material to make it sturdy (specially necessary for pva).

[IRobertI 520]

I think that's because that other cura option to connect supports, so it expands and also connect near supports, making a huge support with even more material to make it sturdy (specially necessary for pva).

I suspected that as well and did some testing on it last night. But it doesn't seem to be the case. Unless I did something wrong while I was messing around with the settings.

[kmanstudios 1,120]

I think that's because that other cura option to connect supports, so it expands and also connect near supports, making a huge support with even more material to make it sturdy (specially necessary for pva).

I suspected that as well and did some testing on it last night. But it doesn't seem to be the case. Unless I did something wrong while I was messing around with the settings.

Hmmmm, now I am confused. Simply because I made the suggested change and it worked.

So, if not too much trouble, could you explain your testing?

[IRobertI 520]

What I thought ultiarjan was referring to is that the support (in your first picture) is wrapping around to the backside of the pillar which seems to be more than it should be doing just because of the horizontal expansion. I thought the option to connect support structures to make them stronger was causing it. So I took a model with a similar shape to yours and played around with the horizontal expansion and that second option, but it didn't seem to be making any difference. At least not for that particular model.

[kmanstudios 1,120]

huh.....do you have a pic of that model? Making the suggested change has solved a great many issues (went back and sliced old models that had the same issue) and I can see where it may be good to 'grow support' a bit to help with areas that do not meet the specified criteria. Probably not often, but something to try when I see a possibility.

[XYZDesignPro 70]

Robert,

Thanks for the tip. Your suggestion to reduce the "Support horizontal expansion" setting has solved a problem for me that has prevented me from using any Cura version after 2.4 because of all of the extra support that was in places that were completely unnecessary.

 

Before and after images when setting this from 3 (default) to 1. Also, as you can imagine, reduced the print time from 3 hours to 2 hours

Never had this problem with Cura 2.4. Hence I have used 2.4 exclusively for production work since it's release. Now it would appear I'll be able to move on to 2.6.1 and enjoy all of the benefits of the ongoing development of this invaluable tool.

There are so many hidden settings in Cura these days without clear explanations as to functionality. Thank heavens for this forum !!!

Thanks again for your valuable tip . . .

[kmanstudios 1,120]

Robert,

Thanks for the tip.  Your suggestion to reduce the "Support horizontal expansion" setting has solved a problem for me that has prevented me from using any Cura version after 2.4 because of all of the extra support that was in places that were completely unnecessary.

 

Before and after images when setting this from 3 (default) to 1.  Also, as you can imagine, reduced the print time from 3 hours to 2 hours  

Never had this problem with Cura 2.4.  Hence I have used 2.4 exclusively for production work since it's release.  Now it would appear I'll be able to move on to 2.6.1 and enjoy all of the benefits of the ongoing development of this invaluable tool.

There are so many hidden settings in Cura these days without clear explanations as to functionality.  Thank heavens for this forum !!!  

Thanks again for your valuable tip . . .

I had noticed the same thing with a few models, but I did not have smooth sides such as your bottle design. I figured it was catching some minor overhang (and there were some recessed areas that did have 'overhangs within itself) but it would go from plate up like you illustrated.

And, yeah, it does kill a lot of extra time in printing as well as waste.

[Labern 774]

In my experience PVA likes continuous flow and not small towers.

I play with horizontal expansion a bit and some models work better with more. Some can get away with less.

If some sections of PVA are small it can underextrude and can easily break. Increasing horizontal expansion can also help with PVA adhesion to PLA.

But all this is model dependant.