Support structure ignored under object
 
Notifications
Clear all

Support structure ignored under object  

  RSS
prus-19
(@prus-19)
Active Member
Support structure ignored under object

Hi,

Sorry this may be a beginners question, just made my first design of an object and tried to slice and print it. It is basically a box that stands on 4 little pillars. As such, there is quite some free space under the bottom of the box, and I wanted to add support structure. I created a support box for that, basically a bit larger than the object itself, and high enough to cover the space under the box. For the area that is outside the 4 pillars the support structure is then sliced. But right in the middle under the box, basically the whole area between the 4 pillars, no support structure is created. What might be the things I should check?

Napsal : 01/09/2019 6:45 pm
bobstro
(@bobstro)
Illustrious Member
RE: Support structure ignored under object

Can you provide a link to the STL file? Better yet, save your work as a project (3MF) file and provide that. It will need to be zipped if you want to upload the actual file. That will make it much easier to understand what you're trying to do. If nothing else, do a couple of screenshots.

I suspect what you're trying to do is add supports where bridging is being used. If you slice the model and spend some time in preview mode, you should be able to verify what parts are bridged. You could try toggling Print Settings->Support material->Options for support material and raft->Don't support bridges.

My notes and disclaimers on 3D printing

and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan

Napsal : 01/09/2019 6:50 pm
prus-19
(@prus-19)
Active Member
Topic starter answered:
RE: Support structure ignored under object

printbox_nobridge

I tried the "Don't support bridges" option and deactivated it...yes now support is created under the box. Looking through the result I can still see some Bridge infill created - does that make sense? If you don't mind, is there any other thing I should improve in settings? After printing a "test frog" this is really just the 2nd try I make, with a simple object created in FreeCAD and exported to PrusaSlicer.

Napsal : 01/09/2019 7:24 pm
bobstro
(@bobstro)
Illustrious Member
RE: Support structure ignored under object
Posted by: prus-19

printbox_nobridge

I tried the "Don't support bridges" option and deactivated it...yes now support is created under the box. Looking through the result I can still see some Bridge infill created - does that make sense?

Are you referring to the light blue in the center?

If so, that's the 1st layer after the support. It's printed above the small gap between support and the supported surface, so is literally printed on air. It prints as a bridge, and you'll notice it looks very stringy when done. That's an inevitable limitation of current consumer-grade FFF printing, unfortunately.

If you don't mind, is there any other thing I should improve in settings? After printing a "test frog" this is really just the 2nd try I make, with a simple object created in FreeCAD and exported to PrusaSlicer.

I'll look some more, but it looks like you're using defaults. You can increase the Print Settings->Support material->Options for support and raft->Contact Z distance if the support is tough to remove. You can't go too far of course, but I find 0.25mm works well.

I'd suggest creating some smaller parts for testing, something that can print in 15-20 minutes so you can do more learning and less waiting. And use less filament. I've got some links to examples here.

Congrats on diving right in with CAD on your own designs. Have fun with it!

 

My notes and disclaimers on 3D printing

and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan

Napsal : 01/09/2019 8:46 pm
Share: