Another 7+ hour print that will likely have to be thrown out

I'm trying to print a part that has a number of very small holes that need to be clear. They do NOT need support. The part also has some significant overhangs that do need support. Because there is no way to preview supports in the Cetus software I just have to play with the support settings then print the part and hope for the best. If it insists on adding support to these small holes then the part is useless since there is no way to remove that support material.  It's even worse than it looks. Down inside of those square holes is a recess for a nut and that recess is full of support material too. It doesn't seem to matter what I use for the support settings it keeps putting support in those holes where none is needed. This is some very minor bridging to be able to span those without support.


You can set the "area" threshold of support to eliminate support from overhangs with area smaller than a certain value.

But it would be nice to see the support in the preview because when we change the settings we don't really know how exactly it will affect the print :)

@Avri89 YES EXACTLY. @JasonWu I think most of us know that you can change various settings to achieve what we want to BUT if there is no preview of exactly what will happen then the only option is trial and error. This costs us a lot of time and money. It's in my opinion the number one reason we need gcode support so we can use a third party slicer.

What really kind of concerns me is that I saw this same argument being made on the UP box forums and the response from company employees seemed to be the same that why is this a problem because you can fix this with settings. Hopefully now they realize this is an issue and we won't experience the same frustration for long. 

The existing support settings are not going to fix this issue. Consider a vertical hole for an M5 screw (allowing for a little bit of clearance) would be enough to trigger support at the 20 mm2 area setting. I know this printer is easly capbable of bridging a gap far larger than that. 

Just to prove the point, I'm now wasting more filament on a test using the 20 mm2 area setting and it already appears that it is will be creating support for even the small M3 screw holes in the bottom of the piece. Note that the cross section area of an M3 hole is only about 7mm2 so now I'm questioning if the slicer is even interested in the support settings. (I'm running this on a PC running Windows 10.)

Again I wouldn't need to waste the filament if we had the ability to see support in the preview.

I put a copy of the stl file in my Dropbox in case Cetus or anyone else might like to try this.

I killed that last one since it was obvious I was going to end up with the same support issues that I had before. For my next test I left the Area setting at 20 mm2 and increased the Space setting to 15 lines. This appears to be noticably better. It did not create any support in the vertical holes but it did create some minimal support in some of the rectangular slots. I think that small amount of support will be removable. I'll let this one finish and let you know how it goes.

I have successfully printed 3 of these pieces on my Trinus printer with no issues. There I'm using Simplfy3D so I can manually decide where support will be placed. Actually I let S3D create his own then selectively remove the support that I don't want before I print. That's a bit easier in this case. It would be really nice if I could use S3D to create the gcode then print that gcode file on the Cetus. The only reason I'm printing this on the Cetus is because I'm waiting for a part for the Trinus so thought "Hey, I have another printer. Why not print this last one on that." Yeah.... Right... why not.

This last one using Area 20 mm2 and Space 15 seems to have worked well enough. I still had support in the rectangular slots that did not need to be there but I think I got them cleaned out.

Cyberhugger, out of curosity what part are you waiting for on your Trinus? I'm still waiting on mine to arrive.

@ cyberhugger,

Have printed with area set to: 0 mm2?

Correction, Have You printed with area set to: 0 mm2?